2/28/07 NOW: OK / KS

[Justin Bailey]

radar returns now showing up north of OKC just east of Enid. looks like the southern part of this system is just getting started.

 

[Jordan Hartley]

Man, the remaining supercell in MO is still Tor Warned and the storm speed has picked up to 45 mph. Also the S end of that complex of storms sw of KC metro still looks dangerous.

 

[Donald Giuliano]

Given the latest Sedalia dewpoint of 55, I'm inclined to give the cooperative sites you cited more credence. Now the question is, how did this moist blob get there? It's almost as though a little bubble of moister air somehow formed north of or broke off from the main blob farther south. Perhaps there is moister air just above the surface associated with the nocturnal LLJ, and the vigorous convection locally mixed it down to the surface?
...

Given that Sedalia (actually, the site is at Whiteman AFB) is now back down to a dewpoint of 52, and given the progression of observations SZL reported, I'm inclined to think that the observations, at least at SZL, were related to the storm modifying its surface environment:

KSZL 010255Z 16008KT 10SM BKN160 17/11 A2937 RMK AO2A PRESFR SLP948 58010=
KSZL 010312Z 15010KT 7SM -SHRA OVC160 17/12 A2936 RMK CONS LTG ICCCCG DSNT SW TS 20SW MOV NE=
KSZL 010324Z 15006KT 7SM -TSRA BKN050CB OVC160 17/12 A2936 RMK CONS LTG ICCCCG OHD TS OHD MOV NE=
KSZL 010340Z 14005G15KT 7SM -TSRAGR BKN050CB OVC160 17/12 A2936 RMK CONS LTG ICCCCG OHD TS OHD MOV NE GR 1/2=
KSZL 010347Z 14005G15KT 1 1/2SM TSRA BKN030CB OVC160 16/12 A2936 RMK CONS LTG ICCCCG OHD TS OHD MOV NE=
KSZL 010347Z 14005G15KT 1SM TSRAGR BKN030CB OVC160 16/12 A2936 RMK CONS LTG ICCCCG OHD TS OHD MOV NE GR 1/2=
KSZL 010353Z 09009KT 3/4SM +TSRAGR BKN020CB OVC160 15/12 A2936 RMK CONS LTG ICCCCG OHD TS OHD MOV NE GR 1/2=
KSZL 010355Z 16007G15KT 3/4SM +TSRAGR OVC030CB 16/13 A2937 RMK AO2A CONS LTG ICCCCG OHD TS OHD MOV NE GR 3/4 SLP944=
KSZL 010356Z 14011G15KT 3/4SM R01/2000VP6000FT TS +RA BKN019 15/12 A2937 RMK AO2A VIS 2 RWY19 LTG DSNT N - S AND W CIG 012
RWY19 SLP944=
KSZL 010412Z 36004G29KT 2SM -TSRA FEW001 BKN020CB OVC160 14/13 A2935 RMK CONS LTG ICCCCG OHD TS OHD MOV NE=
KSZL 010440Z 12007KT 10SM TS BKN030CB OVC100 15/13 A2930 RMK CONS LTG ICCCCG OHD TS OHD MOV NE=
KSZL 010455Z 16015G19KT 10SM TS OVC037 15/12 A2928 RMK AO2A PK WND 24029/0403 CON LTG OHD TS OHD MOV NE PRESFR SLP914=
KSZL 010505Z 31013G25KT 10SM TS BKN035CB OVC100 14/11 A2935 RMK CONS LTG ICCCCG OHD TS OHD MOV NE=

What we see here is that the winds backed around to the SE and the dewpoint rose (as Paul mentioned earlier for points farther west) under the forward flank of the storm. Then as the meso passed by, the winds shifted to the north, and after a little while back around to the SSE as the dewpoint started to fall again (at the very end the next cell starts to impact their observations). This is of course consistent with the passage of a mesocyclone, except that having the dewpoint rise as the precip core passes overhead is not your typical situation. One explanation I can come up with is that there is moister air above the surface which the storm is tapping, and this is being mixed down through a very shallow layer of drier air. Or perhaps evaporational cooling is bumping up the dewpoint a bit, and the temperature down a bit. Or maybe something else entirely is going on, or was going on further west earlier.

Thoughts?

 

[Mark Farnik]

There was a nice hook on that southwestern cell as it passed south of Ottawa about forty minutes ago, but it occluded. The cell still looks extemely nasty, and it could very well go tornadic as it approaches the southern suburbs of Kansas City, which is not good, especially considering the time of night this is occurring.

EDIT: First supercell of the night in Oklahoma has exploded in the last five minutes in Noble County, just east of the town of Perry. Another cell is rapidly developing north of Ponca City. Both are firing along the advancing cold front and just moving into the southwestern part of Tornado Watch #36. Dewpoints are spiking in central and northern Oklahoma, as of 11 p.m. CST Seminole was at 59, Ponca City was at 55 and Tulsa at 58. Since the storms are right on the front, they should tend to be linear in nature, though imbedded supercellular structures with isolated tornadoes are a strong possibility. Looks like the next couple of hours could be pretty rough for the southern parts of the watch area.

 

[CraigFisher]

The line of storms in NC OK has really ballooned up and moving rather quick east. It appears currently to be well ahead of the dry line....for now.

 

[Justin Bailey]

There was a nice hook on that southwestern cell as it passed south of Ottawa about forty minutes ago, but it occluded. The cell still looks extemely nasty, and it could very well go tornadic as it approaches the southern suburbs of Kansas City, which is not good, especially considering the time of night this is occurring.

I really think those cells are elevated. if they weren't then i beleive they would've been TOR warned while passing over Ottawa. appears that re-initiation is occuring west of Emporia and the storms N of OKC appear to be lining up, but i expect the shear to evlove them into supercells in the next 20 min or so.

 

[Mark Farnik]

I figured as much.
The cells in north central OK definitely need to be watched. They're looking rather linear attm, I dunno, there might be a little too much shear present which could push over any substantial updrafts and force them to remain linear.
Also wouldn't hurt to keep an eye on the convection refiring west of Emporia, those cells could run into some of the boundaries left behind by the earlier convection and the results could be quite interesting.

 

[Justin Bailey]

the line appears as if the line gong through tulsa will stay linear, however, brand new development is occuring SE of that line near McAlester, OK. Also, the Nrn end of the line going through tulsa looks like its trying to evolve into more of a broken line of individual cells instead of a solid squall line.

 

[Bart_Comstock]

The cell coming out of Coal Co. Ok into sothern Pitsburg (about to cross US 69) is starting to look fairly nice. Give it a bit and we might see a little action out of this cell. It is well out ahead of the dryline and very isolated as it is heading into a bit more favorable enviromen so keep an eye on this if you are out in the River Valley.

EDIT: My bad, I didn't notice your post about this storm already.

 

[Justin Bailey]

looks like NWS agrees. the Coal co. storm is now severe warned. that cell could get pretty interesting seeing how it is all alone down there by itself. thunderstorms are also rapidly developing around Joplin, MO too now.

EDIT: that last radar frame really shows the entire line now breaking up into individual cells. conditions in E OK and SW MO appear to be changing rapidly

 

[Bart_Comstock]

Well looks like the cap decided to break after all, of course this was after I had to punch in for my night shift at the hotel. The Adair county storm is starting to look semi impressive as well and should pass just close enough to my north that I will get a good look at it from my hotel. Stuff is starting to fire up all over E OK and as it moves deeper into Ark and Mo I assume we will start to see things get interesting, granted that it can stay out ahead of the dryline.

EDIT: well things have quickly become messy across the area. if this systems is going to want to do anything realy impressive anytime soon it will need to really get its act together. So much for an impressive night in E Ok, Far W Ark, unless you just want some lightning and svr storms.

 

[Justin Bailey]

both of the cells north and west of Joplin appear to have some weak rotation developing.

The cell north of joplin is starting to look real nice. pretty decent area of rotation evident and a nice hook developing. begining to look like a classic TVS

 

[Bart_Comstock]

You are right, infact it looks as if it is now TOR Warned. With Lamar and the areas just north of it and in and around Milford, Mo are about to be in a very bad spot this time of night. Let's hope they have their radios on.

Also I would like to mention that Barton is the best name for a county to have if you want to keep tornadoes away.

 

[Justin Bailey]

TOR warned cells now west of Ft. Smith, AR. not sure which one...could be both. rotation is evident on both cells.

EDIT: nevermind, the lastest radar scan made it obvious. its the first cell. the cell south of fayetteville is looking alot healthier too.

 

[Bart_Comstock]

Storms in the river valler are starting to spin up as well as the Ft. Smith metro area is next in line for a tornado warning as stroms exit out of Le Flore Co, Ok. So far we haven't gotten any reports in to the station of anything on the ground. I would alsolook out around spiro, ok.

I would also keep an eye on the storm SW of Poteau, OK in Le Flore Co.

Furthermore, keep an eyeout on the cell in Cherokee Co the south end of the line is trying todo something aswell.