7/13/07 NOW: NE

[Ryan Pfannkuch]

Boy, did I ever get caught off guard today
As of 6 pm CDT, a couple of strongly rotating Tornado-Warned northwest-flow supercells are diving into the North Platte area after initiating up in the Sandhills. No reports of TORs as of yet, but one LSR issued for 3-inch hail.

Hindsight is always what it is, but after checking back at the 12z NAM, it did show at least 30 kts of 0-6 km shear moving into that region...although it sure didn't pick up on the QPF. Northwest flow in July is ALWAYS good for some surprises in Nebraska it seems like...and I'd say today has to qualify. Very curious if anybody is on those storms...

 

[Terry Tyler]

there is a crazy storm crossing I-80 right now...

funny to think they arent even in a see text, let alone a risk area...looks like its fixin to hook out!

might be a strong one with that storm if it gets goin...with no competition ahead of it...it looks straight...

 

[Mike Hollingshead]

I've been sort of curious as to why no watch, not that it matters I guess. Some fashion of a low level jet from the south(not much but something) and some 25 knot mid-levels from the nw and maybe most importantly, that 50+ knot nw upper jet nosing in over those. Then there's the instability. Anything deviates much and wala. Sigh. Been talking to Randy Chamberlain some, who drives trains for UP and is out there, and I think they let that southern one go for the one to its north. I guess it's "high based", the southern one. All I know is I wish I was there, I'd be all over that southern one right now, and likely getting stuck in some sand in the process.

 

[Terry Tyler]

cell south of I-80 looks like its either gonna loose it or go cyclic...

looks like its rearing up for another "whip"

cant wait till the radar updates...

 

[Mike Hollingshead]

I guess they are drifting south with it on gravel roads now. Sounds like the base is pretty high, but he says the updraft has really nice structure. I'm just wondering if it is too high to produce a tornado or not. Wish I could see the base. I haven't noticed any very good velocity couplets for a long time now, since when the northern one was just south of Mullen.

 

[Darin Brunin]

I just got off the phone with Dean Cosgrove and he said that the structure on the supercells out there is incredible, noting that he got two big beautiful mesos in the same photo. Knowing Dean, they must be something special since he has seen a little more than a few NE NW flow sups in his life.

 

[Mike Hollingshead]

Randy reports they just saw a small tornado with the southern one.

 

[Brian Stertz]

Wow...what awesome structure on radar from the Sand Hills southward...riding the instability axis south and in area of 40 kts. eff shear...looks like this supercell may actually make it to the Goodland area just glancing at the SPC meso page parameters ahead of it.