Thread by @NashSevereWx

Morning Update. All timing subject to change.

1/10

1. Storms are now lifting out of north MS and north AL.

2. The 11z run of HRRR model shows most of these storms will continue to move north, the bigger ones hitting west TN, during late morning/lunch. We will see rain late morning/lunchtime.

Then around 4-5 PM a line of stronger storms moves in.

3. Forecast soundings for both the lunch time and mid/late afternoon storms are not concerning. Dewpoints upper 50s, a surface inversion, and very little instability are all encouraging. Shear will be substantial, though, so any storm that can find instability could rotate.

4. Therefore, we will closely watch all lunchtime and early/mid afternoon storms.

The main concern is later tonight.

5. Main round ETA is 10 PM to 2 AM. Severity will depend on whether dewpoints are closer to 65° than 60°, whether instability can get high enough. Shear and upper level support for rotating storms will be plentiful, so if we can "recharge" and get unstable there will be trouble.

6. Even if we don't get unstable enough for tornadoes, there will still be a damaging straight line wind threat with this overnight. Maybe some hail.

Or, maybe all it will be is a lot of rain.

We're more than 12 hours away, so there will be lots of fine tuning to the forecast

7. It is not time to panic. Most data is encouraging for us. Side-eye models, watch what's actually happening to be sure it conforms to what the models say.

Forecast will be updated throughout the day. Use current information. Configure Twitter to show latest tweets first.

8. SPC has the probability of a tornado, hailer, or damaging straight line wind event happening within 25 miles of you right around 5%. It's actually 2% in Nashville generally north of 40 and east of 24, but the risk isn't 3% more or less across any interstate.

9. Have a plan. Know how to get warnings. Get updates. We will update you at least on the hour, every hour, here on Twitter, and in between then as storms approach and arrive. nashvillesevereweather.com/what-to-do/

10. Finally, if you have family, friends, or enemies to the south or southwest in the below areas, make sure they know this may be a horrible tornadoday. SPC issued a "High Risk" for them. Those are rare.