Weather Pulse Blog

Meteorologist Britta Merwin

It was around 3:30pm this past Wednesday June 27, 2007 that the tornado warning for Teller County in Colorado came flashing on to our data computers. I must admit that I was very surprised to see the warning since tornadoes are very rare in that part of Colorado. The tornado touched down around the Woodland Park area in Teller County, which is nestled in the front range of the Colorado Rockies. Unlike the eastern plains of Colorado, this area is not characterized as a tornado hot spot.

Clouds begin to build and rotate above Colorado Springs, Colo., Wednesday, June 27, 2007. (AP Photo/ The Gazette, Bryan Oller)

I lived in Monument only nine miles from Woodland Park and about 20 minutes from Colorado Springs. It is a beautiful area roughly 8500 feet above sea level and is known for being near the base of gorgeous Pike’s Peak, which reaches 14,115 feet into the atmosphere. Although beautiful this is not the typical “Wizard of Oz” like picture that most would imagine when it comes to tornado touch down locations.

This geographical area is best known for creating Rocky Mountain Lows. As air moves up and over the Rockies it is compressed, then when the air descends down towards the plains the air is stretched. This squeezing of the air actually creates vorticity, also known as rotation, and makes a low-pressure circulation that can later develop into the large systems that impact the plains and east coast. Although tornadoes can happen in any state at anytime they are not frequent in areas like Woodland Park because of the geographic characteristics.

Only five tornadoes have been recorded in Teller County over the past 57 years! All of these tornadoes have been small ranging from an EFO to an EF1. These twisters pack winds from 65-110 miles per hour causing damage to trees but little damage to structures. Tornadoes are very hard to predict and are still not fully understood by meteorologists but by looking at climate records it is easier to see that conditions can be prime during certain times of the year for particular locations. All five of these recorded tornadoes in Teller County occurred at the end of June beginning of July suggesting that this time period can have favorable atmospheric conditions for these rare tornadoes.

Remember when NBC Weather Plus alerts a tornado warning it is extremely important to seek shelter right away. The best thing to do is to get to the lowest level of your home in a central interior room like a bathroom or a closet. It is also a good idea to have an emergency preparedness kit with a battery powered radio, non-perishable food, water, first aid kit, and any other survival items.

The Red Cross has a great emergency preparedness kit.

Till next time keep your eye to the sky and stay safe!

Posted by Talia Bluth at 12:31 PM | Permalink | Comments (1)

Gary Archibald, Weathercaster

I have been asked many times over the years: how do you show the maps on TV? How’s that orchestrated exactly? Are you reading from a prompter or is it ad lib?

Well the time is now to answer these important questions.

SLIDESHOW: How We Weathercast

First and foremost, it’s not really that complex in terms of the setup. Usually, the weathercaster and/or meteorologist stands in front of what is technically called a CHROMA KEY (“green screen”). It is exactly what it appears to be. Some studios have a specially designed “backdrop” hung – it’s green as you can see in the photos I have posted here, hence the name – “green screen”.

Here are some of the essential technical information you need to know:

A chroma key is the removal of a color (or small color range) from one image to reveal another image 'behind' it. The removed color becomes transparent. This technique is also referred to as "color keying", "color-separation overlay" ("CSO") (primarily by the BBC), "greenscreen" and "bluescreen". It is commonly used for weather forecast broadcasts, wherein the presenter appears to be standing in front of a large map, but in the studio it is actually a large blue or green background.

The principal subject is photographed/filmed against a background having a single color or a relatively narrow range of colors, usually in the blue or green because these colors are considered to be the furthest away from skin tone. When the phase of the chroma signal corresponds to the preprogrammed state or states associated with the desired color(s), the signal of the alternate background is composited and presented as the output. When the phase of the chroma signal deviates from the chosen color, the principal video is presented at the output. This process is commonly known as "keying", "keying out" or simply a "key".

A chroma key subject must not wear clothing similar in color to the chroma key color(s) (unless intentional), because the clothing may be replaced with the background video. An example of intentional use of this is when an actor wears a blue covering over a part of their body to make it invisible in the final shot.

Monitors and teleprompters help us tell the story

OK. Now, what about telling the story of weather while standing essentially in front of a green wall. Well, there are monitors to help guide the on-air presenter as she/he broadcasts the segment. On either side of the set – off screen, one is able to position himself/herself in such a way to point out key points on maps, graphs, live shot etc… It does indeed take a lot of pratice to get really good at it for most people. It’s not a natural act.

And while we are up there – we are ad libbing 98% of what we are saying (although at the desk when we are presenting weather news items with video, one-on-one reporter stories it’s a mix of teleprompter and ad-libbing at work. We use a hand-held remote to advance the maps/graphics and we are directed via audio cues (that’s the earpiece that you see on-air which is plugged into a wireless pack that we have attached to our waist by a clip.

We are also of course “miked-up”, so that you can hear what we are saying about the thunderstorms in Florida or the wet weather over Portland OR…or the tornado watch over eastern Nebraska. Always check your batteries. I get paranoid about losing power on-air. That’s disasterous. It’s happened a few times in the past. I changed them regularly! You get the idea. We also stand on a mark – it’s a green line – green duct tape to be exact. Our set is lit precisely so we have to present in front of “the wall” on that line without straying off it – otherwise we will either be to light (washed out – over-exposed) or too dark on camera (with horribly unflattering shadows).

Before we go on air we are forecasting, studying the weather - computer models, text, statistical, visual, radar, and data souces as it pertains to the weather. So, we have to know the story and then we use the visually presentation to assist in the storytelling process. The STORY is and will always be the STAR, the FOCUS. We, as on-air presenters are merely conduits who aid in getting the essential information to you the viewer in (hopefully) an infromed, accurate, enlightening, and authoratative manner. In addition, we would like to entertain, as a bonus.

I hope that this blog helps to answer those questions! Love to hear from you if you have any questions concerning the weather and how we do what we love here at NBC Weather Plus. Take care -

Cheers!

Posted by Gary Archibald at 10:26 AM | Permalink | Comments (2)

Web Producer Mara Sonnenschein

Earlier today I was putting together a photo slideshow of animals who foster babies of other species, and I decided to call it Fair-Weather Friends.

PHOTOS: Maternal Animal Instincts

Unlike the true meaning of this expression, these animals actually step in and help babies of other species who are in peril. The real meaning of fair-weather friend is someone who only pals around with you when the living is easy. (Which brings to mind the song 'Summertime' from Porgy and Bess -- you can't get away from weather, can you?)

While seeing photo after photo of dogs nursing cats or pigs nursing dogs, etc., I started to think of the expression 'dog days of summer,' which Michelle Grossman explained so well in a blog entry last July.

A mother cat on Thursday Sept. 9, 2004 suckles two two-week-old dog puppies that were found abandoned at birth in a garbage can in Warsaw, Poland.

What about 'raining cats and dogs'? I've used that expression countless times, but I have absolutely no clue what the origin is. A Google search came up with several sources suggesting that house pets used to hide in thatched roofs made of reeds, and that when it rained the animals would either jump down from or would be washed out of their hiding spots. There are other explanations, however -- some mythological, some sailor-based. The upshot is that no one is really sure where this expression comes from.

Of course weather is often referred to in expressions and clichés that really have nothing to do with what's happening outside. 'A bolt from the blue' or 'thunderstruck' use lightning and thunder as metaphors for sudden change or shock.

Then there are the weather expressions that have been passed down for generations that (sort of) explain or predict weather. Probably the most common example is 'Red sky at night, sailor's delight; red sky at morning, sailors take warning.' While this may have been used by ancient mariners, I was surprised to learn it has biblical roots.

So now I've switched from 'Summertime' to the song 'Red Skies At Night' by The Fixx running through my head. I guess when it comes to music, I'm something of a fair-weather friend!

Posted by Mara Sonnenschein at 03:46 PM | Permalink | Comments (1)

Jackie Meretsky

On CNBC this morning, I heard my friend and colleague Joe Kernen ask "do we have more hours in the day today"? Being somewhat of a jokester, I'm sure Joe was just having some fun with the concept of solstice, but because of the complex relationship between astronomy and meteorology and the cultural and seasonal affiliations, there is ample ambiguity surrounding this concept.

In simple terms, which is the way I like to explain just about everything, the reason why today is considered the longest day of the year for those of us living in the Northern Hemisphere is because the northern hemisphere is tilted towards the sun to its maximum extent thus maximizing the amount of light. The sun is directly over the tropic of Cancer which you are probably familiar with if you're into Astrology. So, more light means a longer day. The sun giveth and the sun taketh away - thus more daylight means less darkness within the 24 hour time frame.

In this 2005 photo, crowds gathered to mark the summer solstice at Stonehenge in England.

Astronomy, astrology and meteorology join forces with the summer and winter solstices and we can can attribute many holidays and customs to them as well. Many cultures celebrate various combinations of the winter and summer solstices, the equinoxes, and the midpoints between them, leading to various holidays arising around these events. Different cultures have found fascinating and creative ways to incorporate and celebrate solstices.

For example, for the summer solstice, Christian Catholic cultures celebrate the feast of St. John from June 23 to June 24. And surely you've heard of Shakespears romantic comedy "A Midsummer's Nights Dream"? Well, Shakespeare obviously knew a thing or two about solstices and equinoxes which determine the midpoint of the seasons, hence "midsummer". Rather than celebrating the mid-season, the Japanese culture celebrate the start of each season with a festivity knows as Setbusan. I wonder if I can convince the powers that be to send me on a world-wide tour to investigate how each culture celebrates the solstices. It would be the meteorological and astronomical equivalent of a political reporter's campaign trail coverage! Wish me luck on my quest.

So, enjoy all that daylight today, make the most of it and just pretend that you have more hours to work with!

Posted by Jackie Meretsky at 10:42 AM | Permalink | Comments (4)

Weather Producer Mike Dangolovich

The Summer season officially begins June 21st at 2:06pm EDT, when the sun is at its northernmost point in the Northern Hemisphere at the Tropic of Cancer. This date marks the summer solstice and is the date that most people think of when it comes to the start of summer. However, while this is true from and astronomical standpoint (known as “Astronomical Summer”), it could be argued that the summer season began weeks ago, and even as early as the first week in May! Now before you think I have gone completely crazy (I may be slightly so but not completely so just yet), let me explain.

There are at least two other beginnings to the ‘summer’ season that you may or may not have heard about before. The first is what is known as “Meteorological Summer”, and its start date varies a bit from place to place due to latitude, elevation, and proximity to large bodies of water. Meteorological Summer encompasses the warmest 90 days of the year, and it typically begins sometime in the first or second week of June, and ends during the first or second week of September. Sometimes the period used is simply the months of June, July and August. Meteorologists and Climatologists often refer to this period when discussing the summer season in general.

Another ‘beginning’ to the summer season is called “Solar Summer”, and it encompasses the 90-day period of the year that the amount of solar radiation is at its maximum. In the Northern Hemisphere, this occurs during the period from the first week in May to the first week in August, with the first day of Astronomical Summer as its midpoint. Note that Solar Summer begins about one month before Meteorological Summer, and this occurs because it takes a bit of time to warm the earth, even when the amount of solar energy available to do so is at its peak.

Looks like the beginning of summer isn’t so simple, is it?

Posted by Michael Dangolovich at 07:16 AM | Permalink | Comments (0)

Gary Archibald, Weathercaster

This is third blog in my series “Weather/Climate and Wildlife”. The focus today is on the mesmerizing world of…ants.

I’ve been fascinated with ants for many, many years, dating back to early childhood, summer afternoons playing in the backyard of my house with my brother and neighborhood friends. Ants, as tiny as there are, make a big impression on the young at heart. Theirs is a world of exploration, teamwork, mechanization, attention to detail, workflow, responsibility, the perpetuation of the species, and ultimately sacrifice. Each has his/her role (the queen or queens- some colonies have more than one, and the sterile female workers) and to that end, each fulfills his/her role with the utmost dedication, ritualistic motivation, and natural genetic code of conduct. It is a life worthy of living because in so doing it is a life for the living, the essential survival of the ant colony, home to thousands, millions of current and future generations of the species.

An ant colony is an underground lair where ants live. Colonies consist of a series of underground chambers, connected to each other and the surface of the earth by small tunnels. There are rooms for nurseries, food storage, and mating. The colony is built and maintained by legions of worker ants, who carry tiny bits of dirt in their mandibles and deposit them near the exit of the colony, forming an ant-hill.

A fire ant cleans itself on the point of a No. 2 lead pencil.

In particular, ants control the air flow, ventilation and circulation of oxygen in their intricate lairs – climate control is essential to optimize the growth of the eggs the queen ant lays during her season. Temperatures at the surface and below ground at daytime in your average garden during peak summertime heat may vary 10 to 30 degrees (depending on geographical location in the western Hemisphere). The cooler earth underground, unexposed to direct sunlight, is ideal for premature ants (eggs, and subsequent larvae alike) to mature, all the while receiving the vital attention on a round-the-clock basis by the army of dedicated worker ants. The depth to which these dens are located (with some limitations, based on the makeup of the ground) determines, to some extent, how cool the temperatures can be. The cool “dens” can be warmed up by the movement and circulation of more worker ants in close proximity. Larvae tend to grow best in a climate controlled 70-75 F.

Periodically, swarms of new queens and males called alates are produced, usually winged, which leave to mate. The males die shortly thereafter, while the surviving queens either found new colonies or occasionally return to their old one. The surviving queens can live up to around 15 years.

So there you have it – climate plays a key role in the perpetuation of a very complex, dynamic, and unique species. Next up, I’ll take a look at bees and beehives. They share similar traits and habits with ants. Fascinating creatures…

Until next time – take care.

GA

Posted by Gary Archibald at 05:33 PM | Permalink | Comments (0)

Bill Karins, Meteorologist

Hurricane Katrina’s impact on our country has vaulted the importance of the NHC (National Hurricane Center) into the forefront of the American consciousness. Since Katrina struck, FEMA has been restructured and retooled at a very high cost and now the NHC wants their upgrade. The battle is between the NHC and NOAA (National Oceanic Atmospheric Administration). Here’s a link to the story from the Miami Herald.

http://www.miamiherald.com/548/story/141782.html

This is government politics at its best. We have arguably the most important weather agency within our government asking for more money and resources on the heels of the worst weather disaster in our nation’s history. Don’t be fooled for a second that Bill Proenza, new director of the NHC, doesn’t fully understand the power of public opinion. He has been and still is harshly critical of the way his bosses at NOAA are spending your tax dollars. He feels the NHC needs much more and that NOAA needs to stop wasting money on frivolous programs.

As expected, his bosses at NOAA aren’t happy with their disgruntled employee. They warned him verbally at least once and recently gave him a formal letter of reprimand. It certainly sounds like the start of a paper trail to unemployment to me, but this has unfazed Proenza. Here’s his quote after getting the latest slap on the wrist: "I'm not going to be silenced. I know my responsibilities and I know what I have to do.''

Now the ball is in NOAA’s court and the political drama is building. Do they dare fire him, knowing full well that the media backlash will be 10 times worse? The headlines on tv and in the newspapers will read something like this. “Outspoken Director of the National Center is axed after asking for more money to protect innocent Americans after Katrina disaster.” Sounds like a PR nightmare to me for NOAA.

Making things even more interesting is that numerous members of Congress are speaking out in support of the NHC director. When it comes to supporting and protecting their voters this is an obvious “hop on the wagon” issue for elected coastal representatives from Maine to Texas.

Watch Bill Karins's interview with hurricane expert Jim Lushine below

So what’s next? I can’t see how NOAA could fire the boss of the NHC just weeks before the peak of the hurricane season and I also don’t see how any new influx of money is coming to the NHC this year. I imagine that a few closed door meetings will take place and that promises of more money to come in future budgets will be made in return for critical silence from Director Proenza. I guess the forecast for political weather theater is the same as everyday weather forcasting: wait, see and enjoy. -BK

Posted by Bill Karins at 01:12 PM | Permalink | Comments (0)

Gary Archibald, Weathercaster

Hmmm… I was driving my car down the Long Island Expressway last week in the afternoon… it was warm, humid, the sun blazing the mercury all the up to 86 degrees – feeling like 91 with the humidity factored in. It was a very summer-like day in the latter stages of spring. The glare of the sun was intense. The sun visors were down as I was driving into the solar blind. Traffic was in fact moving – surprise, surprise…

But what was more attention-grabbing was the sight of this dog, riding shotgun in a late model SUV. As it pulled up along side my car, this canine, his head leaning out of the window, turned his head and looked at me.

Did I mention that the dog was wearing shades?

Isabella, a Pug owned by Linda Felice of Romulus, N.Y., knows that fashion is for the dogs.

No joke. Big, dark sunglasses – the kind that eighties New Wave bands wore in their cheesy, under-produced, horribly written and poorly directed classics that we know and love to this day (at least Generation X’ers of my day). I laughed. That image still puts a smile on my face to this day. Let’s face it – dogs sport fashion too, and weather conditions play a part. In bright sunshine, expect to see Sparky and Princess break out the Oakleys, Ray-Bans, CK, and Gucci eyeglass wear.

PHOTOS: Check out some fine examples of fashionable dogs.

Cheers!

Gary

Posted by Gary Archibald at 05:39 PM | Permalink | Comments (5)

Meteorologist Jeff Ranieri

What a busy month this has been so far... I have had tons of friends coming to visit from California and Florida which is great as it always keeps fun and exciting things in my plans. It goes without saying that having a friend visiting the city is incredible and the added bonus is that it helps to reinvigorate the NYC tourist inside. I should explain that as a New Yorker now and then you can easily get locked away in your neighborhood forgetting that Times Square is just a quarter mile away and bustling with tourists.

This past weekend my friend Scott was in town and he is a theatre nerd in all senses. There is not one show he has not seen or at least knows about. The plan for Saturday was two Broadway shows and dinner. After the incredible night of theatre and Greek food Scott mentioned that I had to come by and see his hotel, The Paramount. It's a chic hotel with a unique twist of old eclectic furniture and clean modern lines. While I thought the lobby was impressive and beautiful he said, "Wait, there is one more thing you will love as a weather guy." I really had no guess what this hotel could have to impress my friend Scott, especially on the topic of weather!

So, we head up into the elevator to floor #5. The door opens to the floor with a big wall length mirror and he says, "There it is." I looked around and said "Scott, it's just a mirror!" Scott, replied with a "HELLOOOO look over there..." My eyes turned to the left side of the huge mirror and there it was.

Weather conditions were sleekly implanted on the mirror!

While it's not a forecast it does show what the current outside weather conditions are. This played exactly into the theme of the clean lines of the hotel and the "Less is more" design theory. I loved it and had to grab the picture to share with my Weatherplus.com readers.

Who knew that weather could look so elegant and modern and become one with the ultimate vanity: a mirror. If you really think about weather and vanity there are many times that weather and our own reflection of the self cross and become one or even mingle closely. When it's raining, most of us (whether we want to admit it or not!) grab the umbrella to stay dry and keep the hair perfect, or the nice suit jacket dry.

It may not be a complete Weather Plus forecast but it is certainly appealing to someone in a rush. I love the fact that just one word lit up can be informative, and useful while being so simple. I'm still trying to think of how we can use something like this as part of our set design! lol.

My only critique on the genius weather station is the word HUMID is missing. The hot humid days will certainly do a number on an NYC day of walking and sight seeing. A humid illumination could inspire lighter dress or maybe even an extra pump of spray or another bottle of water for the day.

I hope you enjoyed this look into how inventive NYC hotels can be just so they can make a mark in your mind to keep you coming back.

By the way the shows we saw earlier that day were "Grey Gardens" & "Spring Awakening" and they were beyond good. Thanks, Scott.

Talk with you soon - Jeff Ranieri

Posted by Jeff Ranieri at 03:43 PM | Permalink | Comments (2)

Weather Producer Mike Dangolovich

While Florida has received some beneficial rains over the past few weeks, the drought over the South has for the most part been intensifying and expanding in coverage over time.

Looking at the current Drought Monitor, severe, extreme and exceptional drought now covers much of Mississippi, Alabama, Georgia and Tennessee and Kentucky.

But some good news in the form of rain is headed towards some of these areas today and tomorrow.

It appears that greater than an inch of rain, with locally higher amounts in thunderstorms, should occur over parts of Mississippi, Alabama and Georgia.

This rain is much welcomed, especially since the current Drought Outlook issued by NOAA shows that the drought is likely to persist in much of the region.

So while the rains over the next couple of days will hardly put a dent in the drought conditions (for example, Birmingham, AL needs more than 16 inches of rain to put the city back to average precipitation wise), in this case, every little bit helps!

Posted by Michael Dangolovich at 02:00 PM | Permalink | Comments (0)

Jackie Meretsky

Early morning television is not easy - in fact doing anything cerebral involving the use of motor skills in the pre-dawn/dawn/daybreak hours is a challenge that requires a strong will, a sense of humor and particularly strong coffee.

Having worked on morning television for almost a decade in many different capacities, I know how critical the relationship between on air talent and producer is, in fact the success of the show is almost entirely dependant on it. What differentiates early mornings from any other time of the day (or shift as we say in the TV world) is that you start the day off for your viewers. People are more vulnerable in the morning and don't want to be turned off or put in a bad mood. At the same time, they require information which isn't always of a positive nature whether its news, sports, entertainment or weather.

That's where delivery comes into play. All that being said, in order for me to start the viewers day off right, my day has to start off at least reasonably right - and I am fortunate to start my day with Kevin Maloney, producer extraordinaire for NBC Weather Plus.

Just another day for super producer Kevin Maloney

I thought it would be interesting to get the "producer's perspective" on the early morning Weather Plus experience. After all, it's not ALL about me. Kevin no doubt has challenges, obstacles and goals in the morning which in some cases mirror those of my own (like waking up in the middle of the night) and in other cases are entirely different.

So Kev, how long have you been with Weather Plus?
About five months.

What was your first day like?
Oh wow. I worked with Michelle, she basically started showing me graphics. My first show was the Plus 5.

Were you nervous?
At first I was really nervous. I didn't know what was expected of me in terms of graphics. Michelle took me under her wing and showed me everything she knew - or everything I could comprehend!

Why are you here?
Well, that's an interesting question. I've always loved meteorology and in particular the challenge of forecasting.

Do you have on-air aspirations?
I do as of recent. Being around great talents kind of makes you want to do it. With the combination of producing the early mornings and my internship at WNBC, I think I'm on the right path.

What time do you wake up... tell us about your commute?
Usually around 12:30am. I get up, shower and leave home at 1:30am. It takes over a hour to get to work and that's with no traffic.

Do you drink coffee in the morning and how much?
I don't drink coffee.

You don't drink coffee?! How do you wake up and stay awake?
I drink soda.

What's the first thing you do when you get into the studio?
I look at water vapor imagery, then work my way to the upper levels of the atmosphere. From there I look at storm reports.

Does Jackie (me) make your morning better, worse or are you indifferent to her (me)?
(big laugh) - I would say much better.

What is the toughest part of your morning?
Probably between 3:30 and 5:00am - that's tough. I'ts hard to get the energy going and I start to get tired. If I can get through that, it's cruise control from 5am onwards.

Why do you wrap your food in so much tin foil?
I happen to like tin foil. It keeps your food relatively warm (especially if you bring eggs from home like I do). You can attribute that to physics.

If you had the choice, would your work on a different shift? Why?
I really enjoy the mornings

Are you a morning person?
I'm really not! It's tough waking up, but once I'm up I enjoy it - if that makes any sense.

Do you take your work home with you (physically or emotionally)?
I guess every meteorologist takes their work home with them because they are always paying attention to the weather. So in that sense, it's not really work cause I'm interested in the weather.

How do you wind down?
I have an hour drive home from work so I listen to music and try to enjoy the drive.
If there are waves, I surf. Sometimes I go to the gym or just hang out in m hammock.

Who is your favorite on-air meteorologist? :)
(huge laugh) Is that a serious question?

Posted by Jackie Meretsky at 11:54 AM | Permalink | Comments (4)

Gary Archibald, Weathercaster

Climate and the animal world (including human beings, of course) have multifaceted dynamic relationships. In my last installment I discussed the harsh, wind-driven, extreme cold of the Arctic climate and its effects on the wildlife that inhabit such geographic locales. I focused on polar bears, the resilient although endangered kings of the North. Mother Nature has designed a perfect creature capable of surviving sub-zero temperatures that are lethal to the vast majority of animals who inhabit the Earth, including humans. The thick fur, weighty body fat and highly tuned respiratory system enable the polar bear to withstand the frigid elements.

In contrast, desert climates – hot, arid, water-deprived – are unique habitats for another group of Mother Nature’s specialists – those creatures able to withstand extreme heat capable – deadly and unforgiving likewise.

Ectotherms, such as snakes (specific species that are found in desert climates), are specially equipped to handle such conditions. Ectothermy refers to creatures that control body temperature through external means – thermoregulation - (Greek: "ectos"εκτος = "outside," "thermos" θερμος = "warm"), such as the sun, or flowing air/water. ECTOTHERMS or so-called “cold-blooded” creatures take on the temperature of their surroundings.

The term is now outdated in scientific contexts. Cold-blooded creatures were, initially, presumed to be incapable of maintaining their body temperatures at all. They were presumed to be "slaves" to their environments. Whatever the environmental temperature was, so too was their body temperature. They are hot when their environment is hot and cold when their environment is cold. In hot environments, ectotherm animals can have blood that is much warmer than warm-blooded animals.

Ectotherm animals are much more active in warm environments and are very sluggish in cold environments. This is because their muscle activity depends on chemical reactions which run quickly when it is hot and slowly when it is cold. Ectotherms can convert much more of its food into body mass compared with a warm-blooded animal.

The Pacific Rattlesnake, a fine ectotherm example, is found throughout a variety of places in California, from sea level on the Pacific Ocean, the inland prairies and desert areas, to the mountains at elevations of more than 10,000 feet.

Along the coast north of southern California, the Pacific Rattlesnake has the territory all to itself. In Southern California the Pacific rattler overlaps the range of several other species and subspecies, except that of the large Western Diamondback rattler along the Colorado River and the southeastern California deserts.

A Western Diamondback Rattlesnake

From Lake Tahoe north, on the east side of the Sierra, you might see the Great Basin rattler; from Tahoe south through Death Valley, the Sidewinder (Crotalus cerastes) and Panamint rattlers; along the Colorado River, the Western Diamondback (Crotalus atrox); in the southwestern area, the Red Diamondback (Crotalus ruber) and Speckled (Crotalus mitchelli) rattlers; and in the Mojave Desert, both the Mojave Rattlesnake and the Sidewinder.

A Great Basin Rattlesnake

In the northern areas of their range and at higher elevations, snakes congregate in the fall at crevices in rocky ledges to hibernate for the winter, returning to these places annually. These spots are known as snake dens.

An albino Western Diamondback Rattlesnake

When temperatures begin to warm in May and early June, snakes come out of hibernation. They remain near the den entrance for a few days, sunning themselves, then make their way to where they will spend the summer. Desert summer climates in southwestern USA can produce temperatures into the 110-120 F range. Desert snakes can function without difficulty under these extreme conditions although they too have their limitations. They rarely go more than a mile from their dens. Most snakes are secretive in their summer activities, hunting at night and remaining inactive and out of sight for days at a time during the digestive period after eating a squirrel or small rabbit. Consequently, more snakes are seen in the spring and fall migrations to and from their winter homes.

Posted by Gary Archibald at 03:58 PM | Permalink | Comments (2)

Meteorologist Jeff Ranieri

Weather is everywhere these days, from global warming hot topics to even my ipod and millions of others. I'm not sure if it's just a coincidence or a subliminal weather related message but my new favorite song is "Umbrella" by Rhianna.

The video is hot and the lyrics are great. The song title reminded me of how much music involves weather.

It's obvious and there's no doubt that songs can evoke tons of emotion and so can the weather separately. That's why I think the mix of music and weather work so well together for people of all ages and backgrounds. What is better than a happy or mellow tune of words with a mix of changing elements of weather? They both really do harmonize well and represent the way we live in a life of constant change.

Ok, off my poetic thoughts now and back to reality ...

This idea of music and weather is so pervasive that some search engines actually have songs separated by weather conditions!

As I was blogging I brought this whole idea of weather and songs up on the set and it produced a gab of answers from the PM Crew.

Here's a look into some of our favorites:

• Here comes the rain - Anne Lenox ( One of my favorites)
  
• It's raining men (a classic)
  
• DJ Sammy (Sunlight another great pick of mine!)
  
• Here comes the sun - The Beatles ( Credit goes to Britta Merwin our weather producer on this one )
  
• Don't go chasing waterfalls - TLC (This ones a stretch - but thanks Allison (our assignment desk manager)
  
• Blame it on the Rain - Milli Vinilli (Our pop history man Jason director chimed in with this and the one below)
  
• Rock you like a hurricane - Scorpions
  
• Sunshine - Jonathon Edwards ( Maral our producer chipped in with this one)
  

Other Notables:

• Let it Snow, Let it Snow, Let it Snow! by Dean Martin
  
• Over the Rainbow by Judy Garland
  
• Raining in My Heart by Buddy Holly
  
• Storm in a Teacup by the Fortunes
  
• Don't Let the Sun Go Down on Me
  
• Baby it's Cold Outside
  
• Beautiful Day - U2

So, even if the top song of the day like Rhianna's "Umbrella" isn't your favorite and the weather will not cooperate, there's always a way to change it.... just crank up your music! Even if the music doesn't work then you can always resort to making your own during the next rain storm or super sunny summer day.

Jeff Ranieri - Meteorologist

Posted by Jeff Ranieri at 11:36 AM | Permalink | Comments (6)

Weather Producer Mike Dangolovich

While Midwest cities like Chicago and Minneapolis have been enjoying nice weather this past week, with abundant sunshine and warm temperatures, cities in the Plains such as Wichita and Tulsa have been inundated with days of rain, and flooding has ensued in several areas. How can one region experience such great weather, while another region right next door can’t seem to buy a ray of sunshine? Blame it all on blocking!

Don't blame it on the rain when it's really all the block's fault.

Blocking occurs when the normal atmospheric movement of weather seems to stop its usual progression. Typically, most places experience a couple of days of nice weather when high pressure dominates, but as the high move on, unsettled weather may follow for a short time as an area of low pressure, or a frontal system, approaches and moves through. However, when blocking occurs, the weather tends to become a “what you see is what you get” proposition as the same type of weather can last for days. Then, if you live in the region where higher pressure is ‘stuck’, you may be with happy with blocking since you receive day after day of sunshine, but a person living where an area of low pressure doesn’t move will not be happy at all, since days of clouds and rain may occur.

Of course, the reverse can also be true. If you live in an area parched by drought, you may be happier with the days of rain that blocking can provide, whereas ongoing fair weather in a drought only spells more drought. In the end, blocking usually spells trouble for somewhere in the Nation since too much of a good thing is a bad thing. It reminds me of the old saying “Everything in moderation."

Posted by Michael Dangolovich at 03:30 PM | Permalink | Comments (0)

Gary Archibald, Weathercaster

Do you ever wonder how exactly animals that live in polar climates – on either pole – are able to cope with, thrive actually, in subzero temperatures, wind-chills, snow and ice, blizzard conditions throughout the year? Conditions, by the way, that would kill a human being in minutes without the proper outerwear protection

This is the first in a series focusing on the fascinating animal kingdom and the dynamic world of weather and climate. First up, let’s examine our friend KNUT – the famous polar bear cub who was abandoned by his mother and is now taken in by the Berlin zoo to the delight of a throng of fans around the world. Knut’s accommodations are less polar arctic and tundra and more climate-controlled Holiday-Inn…at least for a bear. But for his relatives who roam the Far North, conditions are much harsher, and the weather plays a big part of that story. Picture temperatures in Nunavut Canada, where temperatures can approach –49 F or colder! How could any creature cope?

Knut, the polar bear cub, rolls in the sand during his first public appearance in the Berlin Zoo on Friday, March 23, 2007.

PHOTOS: Crazy For Knut

Mother Nature made Polar bears unique and ideally suited to such conditions. A polar bear's fur is white (individual hairs are transparent like the water droplets that make up a cloud) and provides good camouflage and insulation. It may yellow with age. The fur acts as miniature greenhouses, and turns sunlight into heat, which is absorbed by the bear's black skin. Stiff hairs on the pads of its paws provide insulation and traction on ice.

A sow polar bear rests with her cubs on the pack ice in the Beaufort Sea in northern Alaska.

Unlike other Arctic mammals, polar bears do not shed their coat for a darker shade in the summer. It was once conjectured that the hollow hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies. The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 °C (50 °F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing in the guard hairs - in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild peroxide bleach to make the fur white again.

PHOTOS: Lords Of The Arctic

Up next, I’ll examine desert dry conditions and a certain desert dweller that finds cooler temperatures during the blazing heat of the day beneath the sand’s surface.

Thanks for dropping by!

GA

Posted by Gary Archibald at 01:26 PM | Permalink | Comments (4)

Bill Karins, Meteorologist

The best thing about the global weather community is that we are all trying to understand and accurately predict the weather. This common goal along with some healthy competition between government and private sectors is driving the advancement of the understanding of our atmosphere at an incredible pace. At least once a week (maybe daily) there is a new and fascinating weather discovery or technology showing up on the web.

Occasionally, I dig around and find cool links but usually it is a fellow met who e-mails me a link or refers me to a posting about something new and cool in a chat room. So, realizing that if you are reading this you must be a weather nut like me, I thought I’d share one of my favorite weather bookmarks.

As my career advances, I’ve become more and more interested in Satellite Meteorology. I enjoy those moments at work when I can look at the weather and say “Wow, that’s impressive.” More often than not, I will be on this website when I say those words.

Click Here For The Link To Bill's Favorite Page

Here you will see what every major weather event across the globe looks like from space. Currently you can see images of dust storms, volcanoes, icebergs and even forest fires.

Dust blowing over the Red Sea.

When the tropics get going again you’ll find those pictures here also. This site is run by NOAA’s division of Satellite Meteorology and paid for with your tax dollars so enjoy free of charge (kind of).

-BK

Posted by Bill Karins at 09:24 AM | Permalink | Comments (0)

Gary Archibald, Weathercaster

DOPPLER Radar… what would we do with out it. It is an instrumental tool in weather forecasting, tracking and analysis. Anyone who has seen a DOPPLER image of a storm on television for example, is instantly aware of the presence of dynamic active weather. It gives us – forecasters, meteorologists, scientists – the public at large – a look at Mother Nature at work in her often times frightening, awesome splendor.

Let’s take a closer look at one of my favorite weather tools. First let’s define the term RADAR.

Radar is a system that uses electromagnetic waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain. A transmitter emits radio waves, which are reflected by the target and detected by a receiver, typically in the same location as the transmitter. Although the radio signal returned is usually very weak, radio signals can easily be amplified. This enables a radar to detect objects at ranges where other emissions, such as sound or visible light, would be too weak to detect. Radar is used in many contexts, including meteorological detection of precipitation, air traffic control, police detection of speeding traffic, and by the military. The term RADAR was coined in 1941 as an acronym for Radio Detection and Ranging. This acronym of American origin replaced the previously used British abbreviation RDF (which stands for Radio Direction Finding). The term has since entered the English language as a standard word, radar, losing the capitalization in the process.

Let’s now take a look at the DOPPLER component.

Doppler radar uses the Doppler effect to measure the radial velocity of targets in the antenna's directional beam. The Doppler effect shifts the received frequency up or down based on the radial velocity of target (closing or opening) in the beam, allowing for the direct and highly accurate measurement of target velocity.

The phenomenon known as the Doppler Effect is named after Christian Andreas Doppler. Doppler was an Austrian physicist who first described in 1842, how the observed frequency of light and sound waves was affected by the relative motion of the source and the detector.

This is most often demonstrated by the change in the sound wave of a passing train. The sound of the train whistle will become "higher" in pitch as it approaches and "lower" in pitch as it moves away. This is explained as follows: the number of sound waves reaching the ear in a given amount of time (this is called the frequency) determines the tone, or pitch, perceived. The tone remains the same as long as you are not moving. As the train moves closer to you the number of sound waves reaching your ear in a given amount of time increases. Thus, the pitch increases. As the train moves away from you the opposite happens.

NSSL's first Doppler Weather Radar located in Norman, Oklahoma.

During the 1980s and early 1990s, the National Weather Service installed Doppler radars around the USA. In addition, some television stations have their own Doppler radars, while others use images from the NWS radars.

All weather radars send out radio waves from an antenna. Objects in the air, such as raindrops, snow crystals, hailstones or even insects and dust, scatter or reflect some of the radio waves back to the antenna. All weather radars, including Doppler, electronically convert the reflected radio waves into pictures showing the location and intensity of precipitation.

Doppler radars also measure the frequency change in returning radio waves.

Waves reflected by something moving away from the antenna change to a lower frequency, while waves from an object moving toward the antenna change to a higher frequency.

The computer that's a part of a Doppler radar uses the frequency changes to show directions and speeds of the winds blowing around the raindrops, insects and other objects that reflected the radio waves.

Scientists and forecasters have learned how to use these pictures of wind motions in storms, or even in clear air, to more clearly understand what's happening now and what's likely to happen in the next hour or two.

Posted by Gary Archibald at 11:56 AM | Permalink | Comments (0)

Bill Karins, Meteorologist

Naming Subtropical Storms adds to the hype machine. Make it stop!

You can’t change the rules in the middle of the game. I learned that lesson in tee ball on my first day when I ran to third base instead of first. I didn’t like it but I was wrong. So why after decades of record keeping did the National Hurricane Center decide to start naming Subtropical Storms in 2002?

In case you don’t yet see the importance of this issue let me expand. Personally, I don’t care if they start naming every tropical wave. I can handle it and explain it on-air but the fast-paced media world we live in can’t. The message will not be explained properly and the public will be misled which will in turn create fear.

I’ve already had a number of people I don’t know asking me about this amazingly active hurricane season we just started on June 1st. The problem is, it hasn’t been amazing but the public certainly thinks so and I don’t blame them. Two named storms by the first day of the hurricane season certainly sounds unusual and in the media world they call a fact like this sexy. A sexy fact always makes for a great headline and headlines tend to be very convincing.

I’d love to tell the mass media, hey they started naming subtropical storms in 2002 so put an asterisk next to that headline. That’s not going to happen because the mass media loves a sexy headline. As a result you the customer walk away with the perception that the hurricane season and future seasons will be worse than they really are.

Since I and nobody else can control the media my only course of action is to ask the National Hurricane Center to reconsider the naming of Subtropical storms. I’m a numbers guy and I love the purity of historical numbers. So let’s just call Subtropical storms by what they are… Subtropical Storms.

Posted by Bill Karins at 04:32 PM | Permalink | Comments (3)

Gary Archibald, Weathercaster

The series continues… and I hope that you have enjoyed the look at various weather/meteorological devices and instruments that help forecaster like myself, determine and collect valuable data that in turn tell the story about weather.

Next up in the series…a device used to measure wind properties…

A wind profiler is a type of weather observing equipment that uses radar or sound waves (SODAR) to detect the wind speed and direction at various elevations above the ground. Such data is very useful to meteorological and aviation interests.

A radar wind profiler installation

Doppler radar wind profilers operate using principles similar to those used by Doppler sodars, except that electromagnetic (EM) signals are used rather than acoustic signals to remotely sense winds aloft. In a typical implementation, the radar can sample along each of five beams: one is aimed vertically to measure vertical velocity, and four are tilted off vertical and oriented orthogonal to one another to measure the horizontal components of the air's motion. A UHF profiler includes subsystems to control the radar's transmitter, receiver, signal processing, and RASS ((Radio Acoustic Sounding System), if provided, as well as data telemetry and remote control.

The radar transmits an electromagnetic pulse along each of the antenna's pointing directions. The duration of the transmission determines the length of the pulse emitted by the antenna, which in turn corresponds to the volume of air illuminated (in electrical terms) by the radar beam. Small amounts of the transmitted energy are scattered back (referred to as backscattering) toward and received by the radar. Delays of fixed intervals are built into the data processing system so that the radar receives scattered energy from discrete altitudes, referred to as range gates. The Doppler frequency shift of the backscattered energy is determined, and then used to calculate the velocity of the air toward or away from the radar along each beam as a function of altitude.

Indeed, this device is unique to high level wind data collection and analysis… great stuff!

Next time: A look at DOPPLER RADAR systems.

Posted by Gary Archibald at 05:18 PM | Permalink | Comments (4)

Gary Archibald, Weathercaster

For the seventh installment in my series about weather devices and instruments, we turn our attention to weather balloons. My uncle worked for NASA in radio tracking and engineering, stationed in the Caribbean at a USA military base tracking the Apollo missions in the 60s. An exciting time to be sure! He was involved in the launch of weather balloons for flight data and forecasting as it pertained to launches and recoveries. Let’s take a closer look at these valuable weather data collecting instruments…

A weather or sounding balloon is a balloon which carries instruments aloft to send back information on atmospheric pressure, temperature, and humidity by means of a small, expendable measuring device called a radiosonde. A radiosonde (Sonde is French for probe) is a unit for use in weather balloons that measures various atmospheric parameters and transmits them to a fixed receiver. Radiosondes may operate at a radio frequency of 403 MHz or 1680 MHz and both types may be adjusted slightly higher or lower as required.

A rawinsonde is a radiosonde that is designed to also measure wind speed and direction. Colloquially, rawinsondes are usually referred to as radiosondes.To obtain wind data, they can be tracked by radar, radio direction finding, or navigation systems (such as the satellite based Global Positioning System).

The balloon itself produces the lift, and is usually made of a highly flexible latex material (though Chloroprene may also be used). The unit that performs the actual measurements and radio transmissions hangs at the lower end of the string, and is called a radiosonde. Specialized radiosondes are used for measuring particular parameters, such as determining the ozone concentration.

In North America prior to release the balloon is usually filled with hydrogen gas due to lower cost, though helium can be used as a substitute. The ascent rate can be controlled by the amount of gas the balloon is filled with.

Dave Decker holds a weather balloon filled with hydrogen at the National Weather Service in Boise, Idaho, Thursday, March 15, 2007.

Weather balloons may reach altitudes of 40 km (25 miles) or more, limited by diminishing pressures causing the balloon to expand to such a degree (typically by a 100:1 factor) that it disintegrates. The instrument package is usually lost. Above that altitude sounding rockets may be used. After sounding rockets, satellites are used for even higher altitudes.

Weather balloons are launched around the world for observations used to diagnose current conditions as well as by human forecasters and computer models for weather forecasting. About 800 locations around the globe do routine releases, twice daily, usually at 0000 UTC and 1200 UTC. Some facilities will also do occasional supplementary "special" releases when meteorologists determine there is a need for additional data between the 12 hour routine launches in which time much can change in the atmosphere. Military and civilian government meteorological agencies such as the National Weather Service in the US typically launch balloons, and by international agreements almost all the data is shared with all nations.

Specialized uses also exist, such as for aviation interests, pollution monitoring, and research. Examples include pilot balloons (Pibal). Field research programs often use mobile launchers from land vehicles as well as ships and aircraft (usually dropsondes in this case).

Is your interest in weather instrumentation further piqued? I hope so – I’ll have another posting in my series coming up in the not-so-distant future!

Cheers!

GA

Posted by Gary Archibald at 06:03 PM | Permalink | Comments (2)

Meteorologist Jeff Ranieri

We are now in the tropical season and this of course brings a renewed duty to my daily research. In the past week or so I added a full check of the tropics as I start to my shift. This includes plotting where storms are developing in the Atlantic, Pacific and Caribbean.

MORE: Hurricane Central

A few days ago, my brain started to click away and think back to last year at this time. I can remember plotting plenty of regions of thunderstorms in the Caribbean or the Gulf but rarely remember any Atlantic activity this early.

When I checked the maps and discussions about a week ago, there were 2 tropical waves located in the Atlantic. While it is not completely uncommon to get waves forming in the Atlantic this time of year, it does get your mind moving. Remember, the next step after a tropical wave is a depression. We were literally only one level away from two new depressions. Did they form into something larger in the Atlantic??? So far... no. But you can bet though as water temperatures warm in the next month this will make it much more likely.

Remember, last year's predictions never materialized because of El Nino and also African Dust that developed off the coastline. This year is expected to be different as La Nina could enhance storm activity. As far as African Dust plumes playing a part, we will just need to wait and see.

MORE: Information On African Dust

Buckle up and make Weatherplus.com your homepage as this could be a very bumpy season. Time to update the tropical outlook, ciao!

Jeff Ranieri
Meteorologist

Posted by Keith Davis at 10:26 AM | Permalink | Comments (0)

Meteorologist Jeff Ranieri

The lightning capital of the world had major competition on Wednesday with strong Northern Plain storms.

Even though Florida is the lightning capital of the world, it was bested on Wednesday by a state you may not think of when it comes to lightning... South Dakota. Our severe storm set up proved to be quite dangerous on Wednesday evening.

-- Excuse the interruption as we break away now to our storm update center....--

[Weather Plus Announcer:]

AND THE SCORE FOR THE 7:00 HOUR ON WEDNESDAY 6/6/07 IS:

South Dakota: 11096 strikes in one hour

Florida: 257 strikes in one hour

-- We now return you to our Weather Plus blogger Jeff Ranieri.... Jeff??? --

Thanks, Announcer!

As I was tracking the weather live on TV I turned on our lightning tracker and was amazed at the number of strikes in South Dakota. The radar picked up as you mentioned over 11,000 strikes in one hour.

In just a half hour there was over 6,000 bolts. While I even tend to think of the Northern Plains as a snowy and cold place all to often it's a great reminder that severe thunderstorms can happen just about anywhere. On average lightning strikes the earth 100 times per second.

Here's another view of the thunderstorm cell that produced the lightning.

We also took an image of hail our computer tracked with the same storm that was 3/4 inch and possibly larger.

While Wednesday was very busy, we are gearing up for Thursday PM as more strong storms could impact major places like Chicago. Remember, with lightning if you are close enough to hear thunder you are close enough to get struck. The best advice is to seek shelter immediately.

Jeff Ranieri
Meteorologist

Posted by Jeff Ranieri at 11:14 AM | Permalink | Comments (0)

Michelle Grossman, Weathercaster

Right now, at this very moment, is my favorite time of year. No question. I love everything about it. The longer days, the warmer days & nights, and the impending freedom that summer brings. If I had the ability to depress the pause button and freeze time, if only for a few months, I would. Of course, there are few unwelcomed side-effects from summer.

Tuesdays are one of my days off. And like most Tuesdays I often take my beloved lab, Stevie, for a long walk. I live along the Delaware River and he loves to stroll along the Canal Towpath. Stevie especially loves taking a swim in the canal. It's his haven from his begrudging dog days. I guess.

Now while these walks are lovely, especially this time of year. Did I mention I love this time of year??? These walks are not without risk. I've encountered geese, deer, bugs, a snake (one time and hopefully the last), squirrels, even a bull frog. But the worst of all poison ivy. One of the summer side-effects I alluded to above. The reason I bring it up now, is that I noticed, the poison ivy was back in full effect during our walk yesterday. Or at least I think it was. The trouble is I don't know REALLY what it looks like so. But if you're like me you will avoid any three leafed plant.

Do you know what poison ivy looks like?

You'll literally jump away from this small unassuming plant because if you've had it JUST ONCE you will do eveything in you're power not to get it again. Casually asking around the studio today who has, in fact, suffered the wrath of this poisonous plant, the responses were overwhelming. Many of the responses were emotional, "my eyes were swollen shut," and some even showed me their scars to prove how bad the bout really was. Ouch!

And it seems like this year the poison ivy is even stronger than usual. Super poison ivy? I'm itching already!

So with this in mind, I thought it would be helpful to offer these links as a way to identify, prevent, and treat poison ivy:

http://www.weatherplus.com/weathernews/13453081/detail.html

http://www.weatherplus.com/weathernews/13453013/detail.html

Good luck!

Michelle

Posted by Keith Davis at 05:51 PM | Permalink | Comments (2)

Gary Archibald, Weathercaster

This is my sixth installment in my series on weather devices and instruments… (please take a look at the previous entries!)

Next up…and instrument used to measure rainfall…appropriately named …it’s a rain gauge.

A rain gauge is a type of instrument used by meteorologists and hydrologists to gather and measure the amount of liquid precipitation (as opposed to solid precipitation that is measured by a snow gauge) over a set period of time.

Most rain gauges generally measure the precipitation in millimeters. The level of rainfall is sometimes reported as inches or centimeters.

Types of rain gauges include graduated cylinders, weighing gauges, tipping bucket gauges, and simple buried pit collectors. Each type has its advantages and disadvantages for collecting rain data.

Here is a digital rain gauge

Rain gauges have their limitations. Attempting to collect rain data in a hurricane can be nearly impossible and unreliable (even if the equipment survives) due to wind extremes. Also, rain gauges only indicate rainfall in a localized area. For virtually any gauge, drops will stick to the sides or funnel of the collecting device, such that amounts are very slightly underestimated, and those of .01 inches or .02 mm may be recorded as a trace.

Another problem encountered is when the temperature is close to or below freezing. Rain may fall on the funnel and freeze or snow may collect in the gauge and not permit any subsequent rain to pass through.

Rain gauge amounts are read either manually or by AWS (Automatic Weather Station). The frequency of readings will depend on the requirements of the collection agency. Some countries will supplement the paid weather observer with a network of volunteers to obtain precipitation data (and other types of weather) for sparsely populated areas.

In most cases the precipitation is not retained, however some stations do submit rainfall (and snowfall) for testing, which is done to obtain levels of pollutants.

Rain gauges, like most meteorological instruments, should be placed far enough away from structures and trees to ensure that any effects caused are minimised.

Posted by Gary Archibald at 04:31 PM | Permalink | Comments (3)