Severe weather is very likely over the next 36 hours across most of the metro Atlanta area, and yes this does include the risk of tornadoes. The SPC has us in a slight risk for tonight and a slight risk for tomorrow, the images of the risk areas are below:
I do think that parts of the area, mainly the western sections of the region, could be put into a moderate risk for tonight, then almost all of N Georgia for tomorrow night.
Here is the scenario… a very slow moving cold front and big upper level low is crawling across the country. As small disturbances rotate around this low, they will pop storms during the heat of the day in and around this front. Today the front will be in MS and AL, that is where I am expecting the worst of the severe weather to be later this afternoon, right in the moderate risk area. These storms will move towards the area and move though very unstable air, here is the instability for later tonight… (anything over 1000 is considered somewhat high).
The significant tornado parameter for overnight is high in the areas that are shown here in the latest WRF, most of the area N of metro Atlanta are at a 6 out of ten. This means any storm that moves into the area overnight most likely will be spinning and could produce a tornado…
So tonight will be mainly the NW sections of the state for the risk of severe weather (damaging winds, and potential tornadoes) and then the metro area for heavy rain and some strong winds in the morning……
The front, however, hangs back in Alabama and does not move through here until early Wednesday morning. I think that tomorrow will be more severe than today…. Here is the WRF for tomorrow night as the front moves through the area:This is just ahead of the front where the highest shear will be as well. We will also be in the right place of the jet stream overhead for maximized lift. Here is the NAM for the jet stream tomorrow night and we are in the right entrance region (basically this means that the upward moving air will be highest right there) at the time that these storms are going.
Also, the helicity levels will be off the chart tomorrow night… anything above 200 means that everything that is a storm will be rotating … most of the area tomorrow night is at a 400-500….. that is very high…
Tonight we will see some storms mainly in the overnight hours and mainly in the NW, some will be severe with damaging winds and hail the main threat but tornadoes (in the NW) are also possible. This will transition into a thunderstorm and heavy rain type of an event for metro Atlanta in the morning hours.
Tomorrow evening and tomorrow night is when metro Atlanta will see a very good chance of some nasty severe weather. The potential for damaging winds and isolated tornadoes is very possible across all of N Georgia tomorrow night, especially in the metro area…. The timeline for tomorrow night will be from around 6pm through around 2am..
On a scale of 1-10 for tonight I give the area a 4…. For tomorrow night I am going with a 5 for right now, but there is a very good chance that will be raised when the new data comes in…..
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