11/28/05 FCST: Lower Great Lakes/OH & TN Valleys

[Sam Sagnella]

I'm kinda surprised there isn't already a FCST thread for tomorrow but anyways...The 00z NAM is showing yet another VERY favorable setup for severe weather across the southeastern United States, although the area of greatest risk is somewhat more concentrated than the comparable setups of late. The KGAD forecast sounding for 21z Monday shows 1500-2500J/Kg of CAPE (which, as the SPC notes in the 06z SWODY1, is probably overdone) colocated with 400 m2/s2 of 0-3km SRH and 0-1km shear values in excess of 30kt (0-6km >60kt) yields a very favorable environment for supercells and tornadoes across NErn Alabama. Basically the fly in the ointment for tomorrow is going to be instability, but if good insolation is able to materialize across the area, then the significant tornado threat is going to be very real.

Also, storm motion is going to be an issue again tomorrow, so anyone SDSing enough to chase is going to need to exercise caution with average speeds probably going to be around 45-50mph.

 

[Robert Dewey]

Might as well add the Lower Lakes to the list as well (northern IN/OH/ extreme southern MI). I'm currently watching a SOLID squall line from the Gulf to central IL (embedded further north - dynamically driven). This thing is really moving, even with the loss of instability at sunless-06Z. Looking at the vertical velocity fields (among the usual moisture and wind profiles), and the 8KM WRF output - I see no reason for this thing to weaken at all in the next 12-18 hours! Heck - There's even SVRs firing in IA/NE, very near the blizzard warnings...

EDIT: Wow, I just "tracked" a rain shower behind the main squall line over a period from 0330Z to 0700Z, and it was moving at nearly 80KNTS! Of course, that's right under the mid level jet max... Lots of neat features going on the radars right now, that's for sure...

 

[Jared Mysko]

since my first attempt at posting didn't work, again, here is my spin on things for today:

It looks to me like this system is a powerful one that will be one to watch later today as daytime heating increases the energy that it already has. I am especially interested in the fact that the Rocky Mountains are very cold in Arizona. That doesn't seem normal to me but I'm from Canada so what do I know? I've posted an article on my blog today with more on this:

http://spaces.msn.com/members/jaredwalks/

"Inland Cyclones are ten times bigger than hurricanes but suck more or less depending on where you are" - Jared Mysko

 

[Andrew Khan]

I'd say as the storms cross over the southern plateau they will losse some of tere tornadic potential, but still will pose a large threat for wind, hail and rain. Tornadoes are very possible in East TN, so don't mark that off your list yet. Instability becomes much weaker as it moves further east as well.