Thursday, May 31, 2007

Red blue moon?



If you are feeling blue maybe you can blame it on the blue moon that will shine over us tonight (weather permitting).

Tonight will be our second full moon of the month, meaning it is called a blue moon. (Technically, the moon will be full at 9:04pm.) Why is a moon that does not look blue get called a blue moon?

According to Philip Hiscock of the Dept. of Folklore, Memorial University of Newfoundland the saying has been around for more than 400 years! The meaning has changed many times over the years as well.

In Shakespeare's day is had nothing to do with astronomy and had more of a literal meaning (surprise, surprise). It meant rare or absurd event.

The modern definition was adopted in the 1940s. In those days the Maine Farmer's Almanac offered a definition of Blue Moon so convoluted even professional astronomers struggled to understand it. It involved factors such as ecclesiastical dates of Easter and Lent, tropical years, and the timing of seasons according to the dynamical mean sun.

Aiming to explain blue moons to the layman, Sky & Telescope published an article in 1946 entitled "Once in a Blue Moon." The author James Hugh Pruett (1886-1955) cited the 1937 Maine almanac and opined that the "second [full moon] in a month, so I interpret it, is called Blue Moon."

This was not correct, but at least it could be understood. And thus the modern Blue Moon was born.

The interesting thing is there is such a thing as a blue moon... literally!
A blue moon is indeed rare, but can occur if the conditions in the atmosphere are just right. If the air is very damp and moist the water droplets (if they are just the right size) in the atmosphere can scatter the red and green light in the color spectrum. When the white moonbeam passes through a cloud it can turn blue.

Water droplets are not the only thing that can change the moons appearance. The other night when I was in S. Georgia the smoke from the wildfires turned the moon red! The smoke that has been over the metro area today could do the same tonight. So, indeed our blue moon could be red!



In addition to the 'blue moon' you can also see Jupiter tonight. All night Jupiter will be the bright object right beside the moon.


Happy sky watching!



--Chris


Thanks to our friends at NASA for help with this entry

Sunday, May 27, 2007

Bad Air Today...


For the second day in a row and for at least the fifth time in a little more than a month the smoke from the South Georgia Wildfires has returned to the metro area. This morning visibilities dropped to less than 2 miles!

Here you can see the weather reports from Hartsfield-Jackson....

27 09:52 Vrbl 6 1.50 Smoke Haze SCT017 SCT250 70
27 08:52 SE 3 2.50 Smoke Haze SCT014 67
27 07:52 Calm 2.50 Smoke SCT020 66
27 06:52 Calm 2.00 Smoke SCT017 65
27 05:52 Calm 4.00 Smoke OVC015 66
27 04:52 SE 5 4.00 Smoke CLR 66
27 03:52 S 6 5.00 Smoke CLR 67


The smoke came in between 3 and 4 am and has only gotten thicker. The reason why the smoke has gotten so much thicker is because we have an inversion over the city
you might ask?



What is an inversion you might ask? Well, an inversion is when the temperature gets warmer the higher up you go in the atmosphere. Typically, it gets cooler, but when we have an inversion it acts as a cap on the atmosphere not allowing for the air to rise. That keeps the smoke trapped close to the ground rather than letting it disperse.

Once it begins to warm up outside the 'cap' will gradually weaken and allow for the smoke to disperse somewhat. The problem is that with southeast winds expected again tomorrow expect another smoky start to your day.

Because of the smoke the air quality is very poor across northern Georgia today. Right now it is considered unhealthy. That means "more people will be affected by smoke. Most people should restrict their outdoor exertion late evening hours when the smoke levels are low, to avoid high smoke exposures."

To keep up with the latest pollution count you can do so by clicking here.

To find out the action steps you can click here.

The National Weather Service has created a specific fire/smoke Q & A page to answer frequently asked questions. It is pretty helpful. To see it click here.

Other than the smoke the weather looks pretty good for the rest of your holiday weekend. Enjoy, and stay safe!


--Chris

Monday, May 21, 2007

So... How was YOUR weekend?

Isn't that the question that most of your co-workers ask while standing around the coffee pot or water cooler on a Monday morning? Most answers range from yard work, relaxing around the pool, catching up on sleep, or maybe an occasional trip of out town.
But this morning at CBS 46, most of the parents reported that at some point they took their little ones to the latest installment of the big green man movie - "SHREK". I learned upon further conversation that a couple of us not only saw SHREK but found ourselves looking for SHREK as well.
Confused? I can sum it up in four words for you: "Been to McDonald's lately?"
I have. In fact I may have actually hit every single McDonald's in West Cobb and Paulding counties this weekend! SHREK MANIA under the golden arches actually started about a week ago, before the movie had even hit the theatres.
As we all know every child comes out of the womb with some sort of innate sense to migrate toward Ronald McDonald land - and my daughter is no exception. So it was only natural that my child would be compelled to collect everyone one of the SKREK Happy Meal characters by Sunday at 5:00!!!
And I, being the good "O-C-D" mother that I am, was eager to oblige.
We were able to finagle a donkey, a baby SHREK, and a gingerbread man from the poor drive-through souls on Saturday but Sunday was sort of a downer because all we could find were repeats, and the coveted "Puss in Boots" continued to elude us.
I swear if I see one more cheeseburger, small order of fries, and tiny soft drink cup --- I think I'll go crazy.... correct that, crazier!
Needless to say, we have exhausted our efforts to complete our collection in just Cobb and Paulding Counties. We are moving forward. We are expanding our search.... look out Fulton and DeKalb, here we come.

Friday, May 18, 2007

Protect your skin...



The forecast for this weekend is calling for nothing but sunshine across the metro area. While we typically see average temperatures in the 80s this time of year, this weekend we will mainly stay in the 70s.

Even though the temperatures will be very comfortable, do not forget to protect yourself from the sun!!!

How quickly we burn has nothing to do with the temperature and everything to do with the sun angle! Here in May we have a high sun angle (we are only 1 month from summer). So despite the 'cool' temperatures you will still burn quickly without protection!

Here are a few things to keep in mind before heading out with the family this weekend...


1. Wear as much clothing as possible. Long sleeves are best. Also a wide brimmed hat is good. Sunglasses are a must!







2. Wear sunscreen that protects you from both UV-A and UV-B rays. Those are the damaging rays that cause premature aging as well as skin cancer.

3. Finally, know your SPF. This is something that almost no know knew here at the station! SPF (sun protection factor) has nothing to do with the strength of the protection and everything to do with the length of protection!

If you use an SPF 15 it will protect you 15x the average amount of time it takes you to typically burn.

So, if you usually burn in 10 minutes, spf 15 will protect you for 150 minutes (2.5 hours).

Keep in mind if you sweat, get in the pool, or wipe yourself with a towel, that will decrease the effectiveness of the sunscreen. So make sure to apply often. It's better to be safe than sorry.

Now stop reading this Blog entry and get out there and enjoy the beautiful weather!!


--Chris

Saturday, May 12, 2007

wild fires...



The wildfire across southern Georgia and northern Florida continues to rage this Saturday night. As a matter a fact, parts of I-10 and I-75 have been closed thanks to the fire.

The above picture and this one to the left is a satellite picture showing the smoke from the fires. The red dots indicate active blazes (as of Friday afternoon). If you look careful enough, you can see the black areas in between the dots. The smoke plumes stretch well out into the Atlantic Ocean.

The reason why the fires have moved toward Florida instead of scorching move of Georgia is because our winds have shifted to more out of the north and northeast thanks to what was Sub-Tropical Storm Andrea. You can also see what is left of Andrea off the Florida east coast in the above picture.

The same system that has been bringing the big storms to the metro area over the past two days should bring beneficial rain to southern Georgia and northern Florida. The only down side may be that it could also bring lightning. Lets hope the rains bring an end to Georgia's largest wildfire ever.

Have a wonderful Mother's Day! The weather should be warm and dry here in the metro area.


--Chris

Wednesday, May 09, 2007

SUB-Tropical Storm Andrea?!

Say what?? It hasn’t happened very often, in fact, just a handful of times, but we have a “sub-tropical” storm in the Atlantic Ocean. This, as you may suspect, is causing a lot of confusion. Most people know what a tropical storm is, kind of the minor league version of a hurricane. But this hybrid classification comes about because the meteorological dictionary doesn’t quite know what to do with a storm that “looks” like a tropical cyclone with the tell-tale spinning clouds that forms outside the tropical latitude belt.

So how does this come about? Well, at its core, any tropical system is low pressure at the surface, usually fueled by warm water. As you up in the atmosphere, the air remains warm, as forming clouds release heat, which continues to rise, like in this diagram prepared by the Weather Service:


Sub-tropical storm Andrea began as low pressure off the North Carolina coast a few days ago, but then began drifting south of all things, into warmer water. Aloft, there was cold air, not warm air, yet the satellite pictures were taking on the familiar swirl pattern of a normal tropical storm.

So, early Wednesday, the Hurricane Hunter C-130 aircraft probed the storm to find out what was happening and sure enough, they found a center of low pressure and wind fields consistent with a tropical storm. Especially noteworthy were the sustained winds of over 39 mph in a circular core around the center. Even though the system was lacking all of the features of a true tropical storm, it was already battering the South Carolina, Georgia and Florida coasts with higher than normal waves. By elevating the system to some kind of tropical storm status, the Hurricane Center might have just been trying to ensure that the public was aware that something was out there. The spiral rain bands might even bring some sporadic rain to the wildfire ravaged parts of southern Georgia and northern Florida.



Yes, it is unusual that we’re talking about a tropical system this early in the season. After all, Hurricane Season doesn’t start until June 1. So we scoured the history books and found out that there are only a handful of seasons in which storms formed so early. Here’s a breakdown:

Earliest storm: Feb 2, 1952
Earliest year with a storm: March 6, 1908
Earliest sub-tropical storm: Ana - April 20, 2003

In case you’re wondering, a year with an early storm doesn’t necessarily lead to a busy year for storms. For example, 1952 had 7 storms overall and 1908 had 10. However, 2003 did end up with 16 storms after the early start with Ana. An average year has around 11 storms.

One thing is interesting for this season already. Last year, we lacked the large high pressure in the Atlantic that acts as a steering mechanism for storms traveling across the ocean. This year, the high is already setting up. Also, we’re noticing that the tropical Atlantic and eastern Gulf waters are pretty close to 80 degrees.

That temperature is a trigger for storm formation. It’s too early to predict doom and gloom, but so far, some of the signs are pointing to a busy year. Check back with me in August and we’ll see how things are shaping up.

Sunday, May 06, 2007

avoiding a dubious milestone...



When I left work Saturday night it looked almost certain that we would cross over a dubious milestone today. What milestone is that you ask? The 10" rainfall deficit. After the rain gauge at Hartsfield-Jackson somehow avoided the showers and storms that rumbled through the metro area Saturday morning we were left resting on a deficit of 9.99".


I knew there would be very little rain Sunday so I was certain we would be looking at a 10"+ deficit Sunday when I arrived for work. Luckily, we had a thunderstorm develop around 3am right over the airport. That storm slowly worked its way south toward central Georgia, but not before dumping almost an inch of rain (.99" officially)!

So thanks to that overnight thunderstorm our rainfall deficit now sits at -9.13". When is our next chance of rain you might ask? Right now it looks like Friday and into the weekend could give us some rain. If that happens that will help us once again going over 10" on the rainfall deficit for the year.

Still, a 10" rain deficit is not something to be proud of or hang your hat on so remember to conserve water as much as you can. There are still state-wide watering restrictions. Those are as follows...
• Odd-numbered addresses may water only on Tuesdays, Thursdays and Sundays (no hourly limits)
• Even-numbered or unnumbered addresses may water only on Mondays, Wednesdays and Saturdays (no hourly limits)

Some neighborhoods have even stiffer rules than that so if might be best to double check with your local municipality as to what your restrictions are.

We should have some pretty nice weather over the next few days so make sure to enjoy that, but then it's time to pray for some rain!


Have a great week!



--Chris

Wednesday, May 02, 2007

Like Getting A Sunburn On Your Lung!

I’ve never heard anyone describe it like that, but that’s what someone from the American Lung Association said today about what ozone does to your lungs. Now that Smog Season has begun, we all need to pay attention to smog alerts and better understand what ozone is and what it does.

Ozone is created when oxides of nitrogen (NOx) and volatile organic compounds (VOCs) are heated by the sun:



Some types of man-made NOx and VOC are: car and truck exhaust, industrial emissions, power plants, gasoline vapors, and chemical solvents. But these compounds do occur naturally from lightning, biomass burning, and soil. Believe it or not, trees, plants and flowers release substantial amounts of VOCs. So the “ingredients” for ozone are ALWAYS present, but we only measure high levels of ozone when either the sun is very strong or it is very hot and the weather patterns become stagnant.

One of our earliest ever high-ozone days occurred in April 2003. April is a month when the sun angle is high. When high pressure is sitting over the south, like it does nearly every summer, the air mass doesn’t change much. So on one day, the sun will heat the NOx, and VOC and create a certain amount of ozone. The next day, under the same air mass, the ozone doesn’t break down that much. On the next day, the sun creates new ozone from car exhaust, etc. and adds that the ozone left-over from the previous day. So by the third day, you can have quite a problem. When the air mass changes, either by a cold front moving through or rain comes in and washes the NOx ,VOCs and ozone out of the air, we can catch a brief break.

Ozone isn’t our only problem when it comes to air quality. Tiny microscopic dust floating in our air can irritate our lungs and cause breathing problems as well. This dust, called particulate matter (PM) is solid matter or liquid droplets from smoke, fly ash, or condensing vapors that can be suspended in the air for long periods of time. PM results from all types of combustion, such as the incomplete burning of diesel fuel in buses, trucks and cars. PM can also come from burning wood stoves and fireplaces.

The EPA came up with a way to express the Air Quality using a color-coded scale which converts different amounts of ozone and PM into a number between 0 and 300, called the AQI (Air Quality Index). When the AQI is above 100, then a Smog Alert is in effect. Since this is mainly a problem in the summer, Atlanta’s “smog season” runs from May 1 to September 30.

So what should you do when a Smog Alert is in effect? Well, a Code Orange alert is a threat mainly to children, the elderly and people with respiratory illness, such as asthma. We call these people a “Sensitive Group”. If you fall into one of these categories, or care for a child or older person, limit the amount of time you spend outside. This is especially true during the late afternoon or early evening hours from 5 pm to 9 pm. Here is an example of the hour-by-hour readings of AQI from the first day of Smog Season 2007, May 1:



Notice at after 1800 (6pm), the blue line climbs and stays above the red line. This indicates that the AQI got above 100.

The next level of alert is Code Red and this occurs when the Air Quality climbs over 150. At this point, even people who don’t have a history of respiratory illness could be affected by the air and should limit outdoor activity. But people in the Sensitive Group category should not even go outside during Code Red.

Finally, there are times when the Air Quality is unhealthy for everyone. This rare occurrence is Code Purple, when the Air Quality rises above 200.

Each day on CBS 46 News, we will show you the air quality forecast for the next day. You can also see this by going to http://www.air.dnr.state.ga.us/smogforecast/.

Tuesday, May 01, 2007

Here We Go Again....

Ready or not the 2007 Smog Season is here. Ironically, as we move through spring - one of the prettiest times of the year - we also begin moving into smog season, which is environmentally one of the most dangerous times of the year.
Last year we exceeded federal air quality standards 30 times! Put another way - we were breathing unhealthy air for an entire month last year!
The facts are staggering. Almost eight percent of Georgia's children have asthma. Asthma is the number one reason that kids miss school. And hospital studies have shown that the number of children that have to go to the emergency room jumps up almost 40 percent during and after a smog alert day.
So what can you do? Well first, I must say that the news is not all bad. Atlanta was one of only four cities where carpooling increased from 2000 - 2005... and nearly a quarter of a million people carpool in Atlanta each day.
Mass transit, opting to walk or ride a bike, not leaving our cars idling whenever possible - those are all great solutions to cut down on the emissions from our vehicles. Also, recycling and conserving energy are additional ways to help the environment. By putting those ideas into practice we are using less energy and put less of a demand on our power companies.
Throughout the spring and summer we'll be giving you the projected daily air quality index value in each of our weathercasts. We'll also be reminding you about safety tips that you can use when the air becomes unhealthy to breathe.
The summer smog season runs from May 1st through September 30th.