andyhb

Pretty much a no-brainer on the 21z RAP. There's enough columnar CAPE for robust updrafts as well.

The LCLs on the 15z RAP and 18z HRRR are plenty workable for some tornadoes should the thermodynamics verify this way.

Another EF4 tornado confirmed near Tylertown MS on 3/15. First outbreak to have 3+ violent tornadoes since 4/12-13/2020.

High end EF4 tornado confirmed in Diaz AR from 3/14 with 190 mph winds. First violent tornado of the year. https://mesonet.agron.iastate.edu/lsr/#LZK/202503150423/202503150423/111010

Heavy damage reported from the earlier tornado near Plantersville and Maplesville AL, with deaths. Large tornado currently in progress north of Jackson's Gap in Tallapoosa Co. AL.

3 fatalities near Tylertown MS with that earlier large tornado that went through there.

Extensive damage near Poplar Bluff with possible fatalities, trailer park hit.

At least 4 separate large tornadoes in progress simultaneously right now. This is insane.

Large tornado in progress near Des Arc, MO.

Tornado emergency for Van Buren MO.

This one is a monster.

There are multiple large tornadoes in progress simultaneously currently.

Strong to violent tornado in the W STL suburbs right now.

Large, likely violent tornado in progress near the MO/AR stateline near Bakersfield.

Tornado in progress E of Marshfield MO.

Those storms were elevated and did not appreciably change the environment very much.

D2 high risk, only the third ever issued in the modern era of SPC.

Think you absolutely need to consider a high risk for MO and W IL. 12z HRRR is a major tornado outbreak with multiple long tracked supercells.

The 06z HRRR is one of the most extreme solutions I've seen from a high res model, both for today and Saturday.

\ 06z HRRR is even more dangerous around St. Louis into W IL. Extreme shear near these cells with more than enough instability to utilize it.

15 hatched tor added in the D1 generally centered on St. Louis and I-55.

Honestly think there should be a main board thread for tomorrow and Saturday, given their overall potential magnitude.

Incredible 00z HRRR run for tomorrow night. Really leaning towards this becoming a high impact event.

That FV3 (which is a bad model to begin with) is a tornado outbreak with a big cluster of supercells. The NAM 3 km is notorious for being too cold in WAA regimes, which will make it much less likely to generate open warm sector convection. With that said, the convective signature it is indicating there looks like the start of a significant event.

Have strong suspicion there will be a 15%/hatched tornado risk outlined at some point for tomorrow for parts of E MO, NE AR, central and S IL, and W KY (perhaps into W TN). Should the moisture be sufficient (and virtually every model is now showing this to be the case), very cold temperatures aloft, a very powerful shortwave trough blasting essentially right into the warm sector, and very strong wind fields favoring long-lived storms should yield at least a few significant/potentially long-tracked tornadoes in the region.