The conditions are set for a major severe weather outbreak over the southeast on Wednesday and Wednesday night. Meteorologists are becoming very concerned about the potential for a major tornado outbreak, particularly over the Tennessee Valley region. However, parts of northern Georgia are included in the moderate risk area issued by the Storm Prediction Center and the entire state could see severe weather tomorrow.
We went all day long today with nothing on the radar, but things have since exploded over Texas and Arkansas. I will be tracking these storms as they approach and currently have Little Rock, Memphis, and Columbus AFB in Mississippi, looping on my GRLevel III system. GRLevel III software takes in raw NWS NEXRAD data and performs calculations that can determine storm rotation, hail, and tornado vortex signatures, as well as many other pieces of information such as storm height and speed. I will keep these running in the areas that are having the worse weather.
This is a very dangerous weather system, potentially more dangerous than anything we've seen in 15-20 years here in the Atlanta area. Here is some very ominous talk from the otherwise generally conservative Steve Nelson, the chief forecaster for the Atlanta office of the National Weather Service. I've highlighted what I believe is extremely important.
"12Z MODEL RUNS STILL INDICATE SIGNIFICANT SEVERE WEATHER MOSTLY FOR WED NIGHT. SIG TOR PARAMETER /STP/VALUES ARE THE HIGHEST I PERSONALLY HAVE EVER SEEN FROM THE GFS OR NAM WITH VALUES OF 15 TO 20 PROGGED FOR ERN MS/NRN AL/CENTRAL TN 18 TO 21Z WED. RECALL THAT STP COMBINES MLCAPE..0 TO 1 KM SHEAR AND LCL. VALUES GREATER THAN 1.0 INDICATE TORNADOES ARE POSSIBLE AND VALUES GREATER THAN 3.0 INDICATE TORNADOES LIKELY. THESE ARE OFF THE CHART GUYS. THE HIGHEST OBSERVED VALUES OF STP I HAVE SEEN ARE 14 FOR THE APR 2010 YAZOO CITY OUTBREAK AND 16 FOR THE MAY 10 2010 CENTRAL OK OUTBREAK. WE CAN TAKE SOME COMFORT FOR GA THAT STP IS PROGGED TO DROP SOME BY THE TIME THE STORMS GET TO NW GA AROUND 00Z
BUT...UNFORTUNATELY... WERE STILL TALKING ABOUT VALUES OF 8 TO 11 IN NORTH GA AND EVEN 6 TO 10 IN MIDDLE GEORGIA AFTER MIDNIGHT.WE REALLY NEED TO BE PREPARED FOR THIS.
This is very serious weather. The one caveat is how much of an effect the ongoing convection will have on our area, and that is the only reason the SPC hasn't already added a high risk probability for tomorrow's outlook yet.
If you don't currently have a weather radio, now is the perfect time to get one. Please stay tuned to TV, radio, NOAA radio, and DaculaWeather.com for the latest severe weather information. DaculaWeather.com broadcasts all alerts, watches, warnings, and special weather statements directly to Twitter (twitter.com/daculaweather) and by email through our own EMWIN (Emergency Managers Weather Information Network) server where we receive the information immediately as it's issued. The service is free and you can unsubscribe at any time. Click here to sign up http://www.daculaweather.com/email_alert.php