I don't really like the fact that the Storm Prediction Center has yet to outline a specific severe weather area for Days 4-8 on their outlook page. That should tell me that any forecast I have is still primarily pure speculation and still can't focus too much on the current details of any one model solution.
But, I still think that given the way the GFS and NAM, as well as the ECMWF, look a chase to the northwest somewhere is likely on Friday and would like to take a look at what this system has going for it.
CAPE Friday Evening @ 7pm from the 12z NAM
The Same from the 12z GFS
The atmosphere just doesn't seem to be as unstable as I would intuitively think it would be given the amount of surface moisture being advected north into the system. This could be due to significant cloud cover with the low level jet at 850mb pumping that moisture in.
Also, there will be no shortage of lift over Oklahoma and North Texas by around 12pm... which has me a little worried that storm initiation could be earlier than expected and storms might push further east... possibly east of I 35 by late evening.
Look at the Jet Stream Positions from the NAM @ 250mb:
From 18z (1pm) and 00z (7pm)
Up until a day or two ago I would not have really known how to use this. (But thanks to Professor Robert G. Fovell I will give it a shot.)
There are some very key areas of lift typically seen near Jet Streaks like this.
One area of lift is the left front exit rigion and the other is the right rear entrance region. If you look at the Jet Streak along the Red River at 18z you should notice that all of southern Oklahoma is in the left front exit region of the jet. And by 00z all of Oklahoma (just about) is. (GFS has its Jet Streak positioned basically the same).
I would expect from this that significant lift will be in place starting around noon and continuing into the late evening. Overnight it starts to push further east along with the low level Jet at 850mb which really strengthens 0nce the sun goes down along and east of I 35.
But here is the interesting thing to me... I would expect the surface low to also move to the northeast and shove the Dry Line towards or across the I 35 corridor... but none of the models really show this happening. They all keep the Dry Line west of I 35 right now... in fact almost to the Oklahoma Texas boarder.
12z NAM surface Dew Points @ 18z Friday
12z GFS surface Dew Points @ 18z Friday
NAM surface Dew Points @ 00z Friday
GFS surface Dew Points @ 00z Friday
So, if all of this actually comes about just like the models indicate I am not 100% sure what will happen. But I would expect some storms to form in the early afternoon and push east fairly quickly (maybe the low level jet convection we often see?) and perhaps another round of storms firing off of the Dry Line to the west where the best instability and surface convergence are.
So, right now it looks like my favorite spot to be would be north of Wichita Falls Texas (perhaps near Lawton or further north) in the mid afternoon.
I believe our best bet at this time would be to shoot straight north along I 35 and then turn to the west towards storms that fire off of the Dry Line. I am not sure whether we would want to go all the way to I 40 or not... but that is where the models seem to want to break out convection at this time.
So after writing all of this up I still must remember that this is all really all educated (I think/hope) speculation on my part.
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