Well, that didn’t take long. . .a week ago we were enduring the wrath of tornadoes through the Plains and Midwest and this week the tropics, not wanting to be out-done, decided to chip in. Tropical Storm Andrea formed late yesterday and has decided to make an early visit to Florida.
I wanted to continue the theme of showing off the capabilities of the Overshooting Top Detection and Lightning Density products that forecasters at the Satellite Proving Ground for Marine, Precipitation, and Hazardous Weather Applications are evaluating. Andrea has put on an interesting show today as you’ll see below.
The Overshooting Top (OT) Magnitude product (developed by Kris Bedka – SSAI) has been getting quite a workout today over the Gulf and near-shore waters of Florida. Many of the OTs have exhibited a 9-15 degree difference between the OT and the cirrus shield. One OT from early in the loop nearly exceeds the scale I set for the product! Notice how most of the strong OT signatures are seen over water with very few over land in this case. Although wind is expected with a tropical cyclone, these OTs may indicate localized areas of enhanced wind gusts that mariners would have to be made of aware of, even being far from Andrea’s center.
The new experimental GLD-360 Lightning Density product has been very revealing today as it helps to contrast the difference between lighting activity associated with a tropical system and activity associated with continental thunderstorms. Notice how the lighting activity with Andrea starts out relatively quiet, but increases as a squall line develops northwest of Cuba and the Keys. Even so, the lightning activity is not overly impressive as this is 30-minutes of binned lighting strokes. The thunderstorms near the center of Andrea are practically absent of lightning during this entire animation. Meanwhile, the thunderstorms over Louisiana and Texas show very intense lightning activity near the end of the loop.
Pop quiz: why the contrast?
Finally, my email was greeted by some beautiful imagery of Andrea from overnight courtesy of William Straka III from CIMSS at the University of Wisconsin. I have included a couple of these images below for your enjoyment.
This image from the Day-Night Band on VIIRS is very cool as you are seeing the cloud pattern associated with Andrea with very low amounts of atmospheric light known as “air glow”. The bright spots on the Florida peninsula are the city lights. It’s amazing that even with minimal light, you can still get a feel for the vertical dimensions of the clouds.
This enhanced infrared image (375 m resolution) from VIIRS of Andrea says it all!
Thanks for reading!