Was Florida hit by a Tropical Storm or a Non Tropical Gale Force?

October 11, 2011

If you were following SWAT’s updates on Facebook (www.Facebook.com/SWATChasers) Sunday Night, you should be well aware that a large area of disturbed weather struck the East Coast of Florida, packing heavy rain and strong winds in excess of 60-70 mph. During the day on Sunday, a weather feature began to develop over the Bahamas. This feature began to show signs of developing into a closed low pressure system within a larger, more synoptically driven weather system/pattern.  By Sunday Evening, the circulation had tightened on  radar, and velocity data was showing upwards of 70+ mph winds. A semi apparent eyewall like feature also became evident just East of Palm Bay, Florida.

There was much debate in the meteorology community as to whether this area of disturbed weather should have been classified as a Tropical Storm or not. Winds gusted to over hurricane force in several reporting stations along the Eastern Florida Coast, but the National Weather Service and National Hurricane Center remained persistent that the disturbed weather was nothing more than a Non Tropical Gale Force.

Radar data/loops clearly showed a well defined center of circulation/eyewall feature as stated above off the Eastern Florida Coast. Without knowing what you were being shown, at first glance, the radar image below looks like several prior landfalling tropical systems.

So besides the well defined center of circulation off the Florida Coast, why do I believe that this area of disturbed weather should have been classified as a tropical storm? There are several reasons, but for starters, here is what I posted Sunday Evening on the SWAT Facebook page.

“I rarely criticize the National Weather Service/National Hurricane Center, but this area of low pressure center has obviously gained tropical storm characteristics. The area of low pressure system has formed over warm sea surface temperatures, has organized convection over the center of circulation, has surface winds over 35 knots and the strongest winds are near the center. This all combined with Cape Canaveral recently reporting a 69 mph wind gusts is blatantly obvious evidence that we have at least a tropical depression if not a tropical storm off the East Florida Coast. Our viewers in Eastern Florida should be prepared for heavy rain, very strong winds and coastal flooding through the morning hours.”

Shortly after I published that update on the SWAT Facebook page, several reports of 75 mph wind gusts were received along the Eastern Florida Coast from the United States Air Force weather observing stations. The winds were strong enough that the National Weather Service was forced to not only issue High Wind Warnings but also Storm Warnings for the adjacent waters. Storm Warnings are extremely rare in the Southeast during Hurricane Season.

In addition to radar data and reports of winds gusting well over 70+ mph at several official reporting stations, the pressure also began to rapidly drop. Cape Canaveral, Florida saw pressures rapidly fall as the area of disturbed weather approached.

The center of circulation passed very close to Cape Canaveral and their pressure bottomed at 999.5 millibars, a pressure reading commonly found in tropical storms. Nearly all (if not all) of the characteristics needed for a storm to be classified as a tropical storm had been met, so why did the National Hurricane Center and National Weather Service choose not to classify or upgrade the storm to a “tropical storm”? There is still some doubt in the meteorology community whether the area of disturbed weather attained a warm core. A definition of tropical cyclones is that they must have a warm core, which means the temperature in the vertical core of the cyclone extending up through the atmosphere is higher than in the air surrounding it. With the area of disturbed weather over extremely warm sea surface temperatures, I personally believe that at the very least, a shallow warm core was likely present.

The second possible reason that the National Weather Service/National Hurricane Center did not upgrade the storm to an official “tropical storm” could be based off of the logistical nightmare surrounding a possible late evening upgrade. The following was posted by a National Weather Service Melbourne, Florida Meteorologist on an online forum.

“You probably don’t realize what a logistical nightmare this would cause our office to name this thing at such a late hour. We would have to cancel the Gale Warning, High Surf Advisory, Wind Advisory and Lake Wind Advisory that have been up now for two days and replace them with Subtropical Storm Warning. We would need to put out products cancelling the current advisories, and then issue a Subtropical Storm Local Statement, update the Zone Forecasts, Coastal Waters Forecast Hazardous Weather Outlook, our blog and Short term Forecast. Local graphics would have to be updated as well as our forecast grids.”

While I understand his point, I do not agree with the decision. If the storm truly was a tropical storm, tropical storm warnings grab the attention of the public far better than high wind warnings or storm warnings. This area of “disturbed weather/non tropical gale force” caused significant damage and as seen via multiple social media outlets, the public appeared to have had no real idea that inclement weather was likely. Granted, high wind warnings were in place, but again, tropical storm warnings have much more significance on public perception than a high wind warning does.

Needless to say, I 100% believe the area of disturbed weather off the Florida Coast Sunday Night was a tropical storm. Hopefully the system is revisited/relooked at in post season analysis. This means that the National Hurricane Center can revisit and take a second look at the storm to decide if it was actually a tropical storm and add it to the list of 2011 tropical cyclones/historical data.

 

Advertisements

Don is dead but Emily could soon be born

July 30, 2011

Unfortunately Tropical Storm Don did little in the way to offset the drought conditions in Texas and as a meteorologist, I can honestly say it was one of the most bizarre tropical storms I have ever tracked as the precipitation field just fell apart once the storm hit the Texas Coast. Another strong tropical wave is being monitored about 900 miles East of the Windward Islands. This tropical wave is likely to develop into a tropical storm (Emily) and eventually into a hurricane.

Here is the projected forecast paths of some of our forecast models showing where the future Emily may track.

I would look for the National Hurricane Center to initiate advisories on the future Tropical Storm later this afternoon. All interests along the Southeastern United States Coast should monitor the progress of this future tropical storm very closely.


Tropical Storm Don Forms

July 27, 2011

As of this afternoon (Wednesday, July 27th, 2011), Tropical Storm Don has formed across the Western Caribbean with winds of 40 mph. Don continues to look very impressive based off  of satellite images and honestly I would not be surprised if winds are currently stronger than 40 mph. The intensity guidance off of most of our forecast models keeps Don a tropical storm/weak hurricane until landfall and with wind some shear present, conditions are not overly favorable for intensification. That being said, with the impressive organization Don has already shown and with warm Sea Surface Temperatures present, Don could strengthen more than currently forecast.

The majority of our forecast models/guidance take Don to the Northwest, making landfall somewhere along the Texas coast.

Don’t forget that you can book your 2012 storm chase tour with SWAT! For the latest information/schedule/pricing, please visit http://www.SWATTours.com


Weather Wise: Dew Point and Humidity

July 19, 2011

Hello everyone! I’m going to try to start blogging on a regular basis, at least once a week, covering topics that the general public finds either confusing, intriguing and or a combination of the both. The current title of these postings will be Weather 101 for lack of a better name, but don’t hesitate to offer alternative suggestions! I’d also like to throw it out there that I am no English Major, and that these blogs are semi-informal. In other words, don’t look at the quality of the writing, rather, look at the content. Before I get into it, if you have any topic suggestions or meteorological questions, feel free to ask us anytime on our Facebook Page or email me at Brad@SWATChasers.com!

As many of you have noticed this week, it is smokin’ hot outside! So hot in fact that you might have wished the Rapture didn’t flop! This is especially the case if you are living in the Midwest or central United States. Hot enough to cook an egg on the sidewalk? Probably, but don’t expect me to eat it! I’m just not a fan of eggs. But the question remains… Why does it feel so hot? I’ll try my best to explain the differences between Dew Point and Humidity as well as some other meteorological jargon like the Heat Index.

-Why eggs? Everyone knows concrete goes much better with bacon!

Let me throw out a scenario. You wake up, brush your teeth, and stare at your scary morning hair in the mirror before jumping into the shower. After you step out, you notice something in the bathroom has changed! The mirror has “fogged” up and you cannot see your reflection anymore! Well why did that happen?  The answer is pretty simple. When the hot water shot out of the shower head, some of it ended up saturating the air inside the bathroom. You might have noticed this with the steam that was appearing to drift through the air. When this warm, saturated air hit the cold surface of your mirror, the moisture within the air hit or reached it’s Dew Point, or in other words, the temperature at which it took for that moisture to cool, condense and form condensation, or dew.  Condensation is just a fancy word to describe the change of matter from a gaseous state to a liquid state, which is the opposite of Evaporation.

Dew Point is a good measurement for the amount of moisture or water vapor content in the air. Don’t be confused, Dew Point is not the same as Relative Humidity, but they are related. I’ll get to that in just a few. The higher amount of moisture that is contained within the air raises the Dew Point temperature, thus in theory making it easier to form a cloud. When the air temperature and dew point temperature are the same, it results in the saturation of the air. This, depending on other circumstances, can result in dew on the grass, fog or even rain.

Take a sip of coffee or any other caffeinated beverage of choice and stay with me! It will all make sense shortly!

So what is Relative Humidity? Relative Humidity or RH for short, is a calculated value that takes into account both temperature and dew point. When the Dew Point Temperature and Air Temperature are closer together, your RH value will be higher, and the opposite is the case for lower RH values. For example: Temperature is 70° and the Dew Point is 67°… You might hear yourself walk outside and say, phew, it’s humid/uncomfortable, and you would be right! The RH would be just over 90%! However, you walk outside the next day and the temperature is 80° with a Dew Point of 60°. Although the temperature has risen ten degrees, the Dew Point has fallen slightly and the spread between the two is now greater. The calculated Relative Humidity is now only 50%! (Humidity Calculator) This is much more comfortable to the touch.

-Check out this completely unrelated photo of a horse!

Why does a higher water vapor or humidity percentage make us feel more uncomfortable? It has to do with the way the human body keeps itself cool. We humans use the evaporation of sweat on our skin to stay cool on a hot summer day. Since I am no expert on the human body, I’ll try to keep this as simple as possible. When matter changes it’s state, in this case from a liquid to a gas via a means of evaporation, it requires energy in the form of heat. When sweat evaporates off of your skin, it takes some of the heat with it and releases it into the air and away from you, thus having a cooling effect. You can read all of the jargon riddled scientific explanation here.  Now, if the Relative Humidity outside is particularly high, it will be more difficult for the sweat on your skin to evaporate and cool your skin. Think about it like a crowded movie theater. The more popular the movie is (Higher RH), ex: Harry Potter (90% RH), the more difficult it is going to be for you (The Sweat) to find a seat (Evaporate). Basically, the more saturated the air is, the harder it will be for the sweat on your skin to evaporate. This will not only make you extremely sweaty, but it will also make you unable to cool yourself as easily. However, if the RH was lower, the sweat would have ample space in the air to evaporate, and in return cool yourself.

You might be typing away feverishly in a message to my email account asking, “When does RH become uncomfortable?”, and before you click send, let me answer that!

Have you ever heard a meteorologist on television refer to the Heat Index during the Dog Days of Summer? Well now that you have the basic understanding of how Relative Humidity is calculated, Heat Index (HI) is much easier to explain. The Heat Index is another calculated value that takes into account both Relative Humidity and Air Temperature. The result is the “human-perceived” equivalent temperature, or, how hot it feels. Lately, you would say “Too Damn Hot!” I can’t say I would disagree. The following is the equation for calculating the Heat Index.

 HI = c_1 + c_2 T + c_3 R + c_4 T R + c_5 T^2 + c_6 R^2 + c_7 T^2R + c_8 T R^2 + c_9 T^2 R^2\ \,

-There are no parentheses, so where do you start now?

If you are a human being like myself and not a super computer, you can use this much easier to comprehend chart that I have stolen, sorry, borrowed from Colorado State University.

Heat Index Chart

-(HI) Chart Credit: Colorado State University

The Heat Index is the number where your Air Temperature and Relative Humidity cross on the X and Y axis. For example, if your air temperature is 90° and the RH is 85%, it will feel like a balmy 117° outside. Not too tough. Lately, 2/3 of the United States have been in or on the fringe of the “DANGER” zone. If you would like to read a brief history of the Heat Index in regards to recent records in Cincinnati, OH, click this link to travel to the Wilmington, OH NWS Page.

Well, I believe I have typed enough here for everybody to digest for a few days. I know this because 6 of my 8 fingers have fallen off and I am typing with my two remaining pinkies. Hopefully you learned something today in today’s WEATHER 101 class, taught by Brad Maushart, co-founder of the SWAT Chasers and SWAT Tours. Always Remember, some are Weather Wise and some are otherwise… don’t be the latter. Again, if you have any questions, comments, complaints or suggestions, please email them to Brad@SWATChasers.com. If your questions are good enough they may be featured in the next Weather Wise segment!


Tropical Storm Bret

July 18, 2011

As of 8:00 PM this evening, Tropical Storm Bret had formed off the East coast of Florida with winds of 40 mph. Bret is moving generally meandering off the coast of Florida at about 2 mph. Steering currents are very weak and there is still some uncertainty as to which direction Bret will ultimately turn. Most of our forecast guidance generally tracks Bret to the Northeast away from the United States Coast, however with weak steering currents, there is a possibility that Bret could still have a few tricks up his sleeve.

Personally, I think a weak mid level cyclone to the North of Bret will help steer Bret away from the coast and out to sea in about 36-48 hours. With warm sea surface temperatures and weak shear, Bret will likely strengthen into a strong tropical storm by late Monday and possibly a weak hurricane by Tuesday. A Tropical Storm Watch is in effect for the Bahamas and interest along the East Coast of Florida and in the Bahamas should monitor the forecast and track of Bret very closely.

As a reminder, we are now accepting reservations through SWATTours.com for the 2012 Severe Weather and Tornado Season! If you or a friend has ever wanted to go storm chasing, next year is your chance with SWAT!


Severe Weather Update for Wednesday, 5-25-11

May 25, 2011

Hey everybody, Brad Maushart here. I’m writing this to update everyone on impending weather situation across most of the Midwest, including Illinois, Indiana and Ohio. This could be a very dangerous situation, similar to what has taken place this afternoon in the plains. I will remind you now to keep a weather radio handy at all times, especially one that is battery powered, so if the power goes out in a storm, the radio will still be operational. With that said, lets get to the briefing.

Tomorrow, severe weather initiation will take place sometime between 2 and 4pm in Indiana, a few hours earlier perhaps in Illinois, and later into the evening in Ohio. The same low pressure system that triggered the severe weather outbreak across the central plains will slide off to the east, into the Ohio Valley by mid afternoon. This will bring with it the counterclockwise flow of winds, and since we will be on the eastern side of the low, we will have a rich flow of moisture along with a predominantly southerly flow of winds that will help to raise temperatures and in turn help the storms to become even more intense as a warm front will then surge northward across Indiana in the afternoon hours.

According to the SREF “significant tornado ingredients” model, one of the tools that we use to forecast severe weather, it places an area of 40 over southern Illinois and west central Indiana by 21z, or 5pm. This number is very high, and could mean that the right factors are coming together at the same time to encourage not only severe weather but also the threat of tornadoes. Below is an image of the model.

SREF Model

Note the area of "40" draped over IL and IN. 21z = 5pm edt.

Again, all the models have come into an agreement with one another that a significant severe weather outbreak will be taking place tomorrow afternoon across the Midwest. Take precautions now so you are ready when or if the dangerous weather situations present themselves. Again, this is not to panic you, rather to inform. Just be alert and make good decisions.

If a tornado WATCH is issued, storms have the right ingredients to form a tornado. If a WARNING is issued, or if the sirens sound in your town, take shelter immediately. A WARNING means that Doppler radar has indicated a strong area of rotation within a storm or that a spotter or chaser has visually confirmed a tornado. Get to a basement or storm shelter. If one is not available, the next best options would be a crawl space, a neighbors home, or the most interior room in your home. Never stay in a mobile home or trailer, get outdoors in a low lying spot and lie flat or move to a neighbors house or shelter. For more weather safety tips, please visit the National Weather Service’s website, http://www.nws.noaa.gov.

Again, tomorrow looks to be a big severe weather day across the state of Indiana, as well as Illinois and Ohio. Please keep the weather radio on, your television tuned into the local news and your attention on our website and social media pages (Facebook and Twitter) for all the latest updates on the situation as it unfolds.

-Brad Maushart