Possible Southeast Tornado Outbreak
I will be ‘live blogging here’ tomorrow April 27 as the storm system approaches, enters and passes the local area. Main focus will be on the local counties, but I will relay information concerning east Alabama and most if not all of Georgia.
You can follow along here on the blog, here on my FaceBook Page – http://www.facebook.com/pages/Cataula-GA-Weather-Alerts/220151324667478, or here via Twitter – http://twitter.com/CataulaGaWX.
At this time it still appears the worst of the storms will stay to our north, as mentioned on Monday. That doesn’t mean we are out of the woods. Hopefully we will not see any tornadoes in the local area, but we all know all it takes is strong wind upwards of 50mph to down trees and power lines causing damage to structures. You may know them as straight line winds, or down burst winds.
Our biggest concern tomorrow will be the development of ‘supercells’ capable of producing tornadoes and severe thunderstorms. We will also have to watch for ‘squall line’ development ahead of the cold front the closer it gets to the area. A ‘squall line’ is also capable of spinning up a tornado, along with severe thunderstorms containing heavy precipitation, hail, frequent lightning, and strong straight line winds.
Here is a graphic from earlier today showing when to expect the storms in you area:
The latest run of the Bufkit GFS3 [00z / 8pm] still shows the most active weather coming through the local area between 6pm and 12 midnight. This does not preclude other severe weather in the area at any time tomorrow. It’s also showing towards our west before the storms arrive here to be the more active area.
Here is the latest Hodograph showing CAPE, Helicity and Shear for 0300z / 11pm April 27.
One formula for forecasting possible severity of storms is ‘Energy Helicty Index’. The formula is Helicity × CAPE / 160,000.
The EHI for this particular graph is 4.711325.
Greater than 1: Supercells likely
1 to 5: Possibility of F2, F3 tornadoes
5+: Possibility of F4, F5 tornadoes
I can not stress the severity of this situation or adequately without fearmongering.
Disclaimer: I am not a meteorologist. Models are used for forecasting. Nothing is set in stone for good or bad.