Severe Risk Sunday night
Tornado probabilities Sunday night
Area most likely to see storms and Tornado watch soon
Storms are ready to fire up to our west. After a relatively quiet day, it is about to get active for northern Louisiana, southern Arkansas, west Mississippi and west Tennessee.
A developing storm system diving to the south will mix with some warm and unstable air along the Mississippi River. These storms will turn severe this evening and overnight to the west. There is a good likelihood of severe thunderstorms and long-track tornadoes in the states mentioned above. We are anticipating a new tornado watch to be issued anytime for those areas.
Risk Areas: The storm prediction center has placed north Louisiana, southern Arkansas, west Mississippi and west Tennessee and southern Kentucky in a "moderate" risk for severe storms. A "slight" risk extends into west Georgia for the early morning hours on Monday.
Georgia risk? We have a couple of things in our favor to help weaken these storms as they move in. First, a wedge of cooler air is over us today. That is giving us the clouds, mist, drizzle and cooler air today. The atmosphere is also more stable over us. If the wedge holds, the storms will begin to weaken as they move into that wedge. Also, the timing of the storms moving in during the morning hours will also enhance the cooler air in place. That will also help to reduce the strength.
Uncertainties with forecast? The wedge often gives us some difficulties in forecasting. It is very hard to tell exactly when it will erode. If the wedge of cooler air that is protecting us, erodes before the storms move in, they could maintain their strength and keep the storms strong. If the wedge holds, it will help these storms to weaken and protect us from a widespread severe weather outbreak.
My thinking on Timing: I think the weak wedge will hold overnight and begin to erode as the storms move in. The line will push into NW Georgia between 6am and 8am. (A little later than my thinking earlier today) The line will continue pushing east into metro Atlanta between 8am and 10am. The line continues moving south through Atlanta and southward from 10am-1pm.
My thinking on Intensity: I expect a few strong storms as the line moves into northwest Georgia. Don't be surprised if there are a few severe thunderstorm warnings as the line moves in. Then, the storms will gradually weaken as it moves into the more stable air. We will still have some thunder and lightning as it passes, but the storms will move to below the "severe" threshold.
Check out the video for a graphical timeline and explanation!