11/10/04 FCST: OK/AR

[Andy Wehrle]

SPC has a low-end slight risk (15-15-2 Hail-Wind-Torn) over much of eastern Oklahoma and western Arkansas. TWC surface map shows approaching partially-occluded cyclone. Not the greatest of setups due to limited moisture return, and probably not worth a long-distance drive, but just curious if any of the "Normanites" and others in the vicinity are planning on heading out today for a late-season long shot?

 

[Glen Romine]

Well, I'd be looking back to the west, behind the stratiform rain band, closer to the upper low. There is a prefrontal trough, which may eventually merge with the dryline, in a region with at least modest heating and dewpoints approaching 60 F. There is reasonable moisture advection taking place ahead of this feature, and with the upper low drifting ese should allow sufficient mid-level cooling for storms to develop. The shear will be borderline this close to the upper low, but probably adequate for some storm rotation and marginal hail. As for tornadoes, while shear is quite reasonable - I have a hard time seeing adequate low-level buoyancy developing, but would note that the RUC forecast dewpoints lag observations, so maybe 500-1000 CAPE isn't completely ludicrous.

Glen

 

[Bill Schintler]

Chase target for today, November 10

Chase target:
Denton, TX (35 mi NW of Dallas).

Timing:
4-5PM, CST.

Storm type:
Primarily linear, with a few “miniâ€￾ supercells possible. Any severe weather will be isolated in nature.

Discussion:
A closed upper-level system is tracking slowly to the east along the KS/OK border. A modest, shallow moisture return in ERN TX is underway, with the FWD morning sounding showing a well-mixed 170 mb deep moist layer, with a 50 mb deep layer of 13C (56F) dewpoints just above the boundary layer inversion. A fairly large curved hodograph was also noted from this location. Later this afternoon, surface temperatures will rise to about 72F (a few degrees higher in breaks in the ST layer); as 700 mb temps fall to about 3C and 500 mb temps to -14C; resulting in modest MLCAPEs to 500 J/kG and LI’s struggle to dip below 0C. Despite this limited instability and the fact that the strongest synoptic-scale forcing is to the north in OK where linear stratiform precipitation is underway, expect isolated small-scale supercells to the south and east of the stratiform precipitation in areas that see some insolation – and it also appears as though shear will not overwhelm the limited thermodynamics.

bill

 

[Sam Sagnella]

MD out for central and northern OK highlighting the risk of marginally severe hail and winds. low is currently around Woodward Co. per mesonet, with CF/DL extending south from there.

http://www.spc.noaa.gov/products/md/md2400.html

 

[Mickey Ptak]

a

Instability is getting a little better now at kokc.

http://www.caps.ou.edu/wx/p/20041110/r/spm...nd/KOKC-snd.png

If I didn't have class tonight I'd be out just for the hail of it.

Mick

 

[Glen Romine]

SVR box just issued, and a few isolated cells starting to ramp up, including one just west of OKC and another south of Enid. Might be worth checking out if you don't have much else to do over the next two hours.

Glen

 

[Jeff Piotrowski]

OKC Storm

Storm just SW OKC looking good weak shear.

 

[Glen Romine]

Probably should be under a now thread, but a tornado warning just issued for Oklahoma county, for the cell near Spencer. Had been outflow dominated, but in the last scan showed a strong inflow jet, and a TVS signature, and so the warning I guess. Wonder if anyone ventured out to take a look.

Edit - see that storm spotters reporting a tornado just east of Spencer.

Glen