What is a rainbow cloud?

WHAT IS A RAINBOW CLOUD?

BY: Mike DeNora

A rainbow cloud is a very unique atmospheric phenomenon that occurs when the sunlight spreads all of the colors of the rainbow across a cloud. Sometimes if the shape of the cloud resembles a fire, like the one on the right, they can also be considered fire clouds. In weather these types of clouds are known as circumhorizontal arc. The rainbow tint is caused by ice crystals in a cirrus cloud acting as miniature prisms. This is the opposite of "true" rainbows that consist of water droplets. Sunlight hitting these ice crystals then spreads out upon contact, creating the seven colors of the rainbow. Rainbow clouds are common in the atmosphere but can be hard to see, as an individual must be located at the perfect angle between the sun, cloud, and themselves, at ground level. This angle must be at least 58 degrees for any coloration to be seen. In the United States, these rainbow clouds are most seen during the summer months at the right latitude and location. When considering the atmosphere's unique features, rainbow clouds, are considered to be one of the most impressive phenomenons.

HOW DO YOU LABEL THE WEATHER MAP?

Written by: Brian Neudorff

I got a question yesterday from the "All Skate" Thursday blog post asking the following, "When you look at a "current weather map" you see the locations of highs, lows, cold/warm fronts. What indicator(like wind/temp/pressure) is most important to showing you where the specific location of the high/lows are, if you were looking at a blank map?" I though this was such a great question that it deserved its own blog post.

The top graphic is what you would see on a daily basis when we deliver the weather during our broadcasts. It is the satellite & radar composite with fronts and the different pressure centers superimposed on it. Determining the locations of these different features isn't that complicated. Sometimes it can be as easy as looking at the radar and satellite, at least to get a general location of these features. The next step would be to look at a surface map. I have a couple of examples below.


The surface maps plot the current temperature, pressure, wind speed & direction, as well current dew point. All of these are very important in figuring out where to place fronts, highs and low. In the above graphic I really couldn't use wind speed or direction to know where to place the front or high pressure. Here I had to look at the different pressures and find the highest pressure reading for the high. For the warm front I used dew point temperatures. They are located in green below the air temperature listed in red. Most of the dew points to the left of the warm front were in the upper 60s to near 70 where as the dew points on the right were more mid to low 60s. This told me that the air with the higher dew points was the more moist and humid air mass coming from the Gulf.


Again I couldn't really ues wind direction change to find where to place the fronts. I already told you how I determined the position of the warm front. I used the same method for the cold front. The dew points behind the cold front (to the left) were in the 50s where as the air out ahead of the cold front was very warm and moist as dewpoints were in the 60s & 70s.

Some other ways woud be dramatic change in direction in wind over a short distance. For example had this cold front been strong winds may have been coming out of the northwest behind the front but out of the southwest ahead of the front. That dramatic change would also be an indication.

There are other ways but looking at the different reporting stations plotted on a map and knowing temperure, dew point, wind speed & direction as well as pressure allows a meteorologist to locate and plot fronts and either high or low pressure centers.

HUMANS EXTINCT IN 100 YEARS?

Written by: Bob Metcalfe

Yea, you read the title right. This guy at left, Mr. Frank Fenner, says that homo sapiens will be extinct within 100 years. I'd call him nuts, but the man helped eradicate small pox... which most would consider a fairly credible activity to add to one's resume.

I read an article in the Herald Sun, an Australian newspaper that says he brought it up in a conversation, and that the subject was quickly changed to other "more impressive" things he's done. It's pretty weird.

So why is this in the weather blog? He chalks it up to global warming. He says its become an "irreversible situation." Here's a quote from the article:

"Before this century is over, billions of us will die, and the few breeding pairs of people that survive will be in the Arctic where the climate remains tolerable."

Hmm. Food for thought I guess.

If you'd like to read the full article you can find it by clicking here.

ALL-SKATE THURSDAY (6/17)

Written by: Brian Neudorff

If you're new to the all-skate format it's pretty easy to participate. This is your chance to ask any weather or earth-science related question, (I almost put ask any question but that could get dangerous) and we will do our best to answer it. I know there are still some questions out there that haven't been answered yet. Don't worry we are working on it or we like it so much that we will use as a possible blog topic in the future. If we haven't gotten to the question feel free to ask it again and we will look into it and answer.

TROPICAL DEVELOPMENT ON THE HORIZON?

Written by: Brian Neudorff

Over the weekend and early this week there has been a tropical wave getting some attention from the National Hurricane Center and other weather forecasting outlets. I'll be honest I was out of town for the weekend and really didn't pay much attention to this disturbance.

Although it has been over some favorable waters in the Atlantic there are a lot of things working against this storm. It is still 1100 miles east of the Lesser Antilles Islands, and it will soon be moving into stronger wind shear. Even the National Hurricane center has downgraded the likelihood of development from 60% to 30% this morning here is their discussion:

SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THE LOW PRESSURE AREA LOCATED ABOUT 1100 MILES EAST OF THE LESSER ANTILLES HAVE BECOME LIMITED THIS MORNING. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BECOME LESS FAVORABLE FOR TROPICAL CYCLONE FORMATION DURING THE NEXT DAY OR SO. THE POTENTIAL FOR DEVELOPMENT HAS DECREASED AND THERE IS A MEDIUM CHANCE...30 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WEST-NORTHWESTWARD TO NORTHWESTWARD AT ABOUT 15 MPH.

Another factor working against this wave is climatology. Only one storm form has ever formed between Africa and the Lesser Antilles Islands in the month of June-- Tropical Storm Ana in 1979.

NOT AS COLD AS LAST JUNE

Written By: Scott Hetsko

Most people I bump into seem to be a little nervous that this Summer is going to be another without much sizzle. Consider the first two weeks of June compared to last year. We are 4 degrees warmer on average for high temperatures. We have been quite wet so far with more rain coming Wednesday.

Once Wednesday's storm moves away, much warmer air and sunshine will pour into Western New York. We expect mid 80s Friday with a chance for a few towns to reach 90 degree on Saturday. An overall drier pattern is forecast as the Jetstream will move well in Canada from Friday through much of next week!

HOW THE HECK DOES THIS HAPPEN?

Written by: Bob Metcalfe

I'd like to thank Beth from Butler, NY for sending us this picture you see. Just so you know, Butler is on the far east periphery of our viewing area in eastern Wayne county.

I was quite surprised on the time frame of this picture. She said that this poor, unsuspecting tree was struck by lightning in her yard on Saturday morning. Now I live in Irondequoit and I had nothing more than a few sprinkles fall during the morning. It goes to show you that even a weak storm with just a strike or two poses a threat.

But why is it that trees explode as they are struck? Wires don't explode when they run electricity right? There's actually a very simple explanation.

Lightning is hot. You don't need me to tell you that. But it's so hot that when it strikes and object like a tree, it flash boils all the water and gases contained within it. We all know that there's water contained in living wood, remember that hiss you hear when you throw a fresh log on the fire? Well this rapid expansion of gases is obviously too much for the tree to handle so the end result is what you see above.

Bottom line, and like we tell all the classes we visit during the school year: trees aren't a good place to hide during a thunderstorm, no matter how much lightning there is.