[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 151904
SWOMCD
SPC MCD 151903 
NEZ000-SDZ000-152130-

MESOSCALE DISCUSSION 1690
NWS STORM PREDICTION CENTER NORMAN OK
0203 PM CDT THU JUL 15 2004

AREAS AFFECTED...SERN SD...ERN NEB

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 151903Z - 152130Z

TSTMS EXPECTED TO FORM QUICKLY NEAR THE SD/NEB BORDER OVER THE NEXT
COUPLE OF HOURS. ACTIVITY SHOULD REACH SEVERE LEVELS RAPIDLY. WITH
VOLATILE ENVIRONMENTAL CONDITIONS DEVELOPING...A TORNADO WATCH WILL
LIKELY BE NEEDED.

LATEST SATELLITE LOOPS WERE SHOWING THICKENING CU FIELD NEAR OUTFLOW
BOUNDARY/WIND SHIFT INTERSECTION ON THE SD/NEB BORDER AREA NW OF
O'NEILL NEB. AIRMASS IN THE WAKE OF MORNING MCS WAS QUICKLY
RECOVERING. STRONG HEATING AND LOW 70S DEWPOINTS ACROSS CNTRL NEB
WERE RESULTING IN MLCAPE VALUES CLIMBING TO AT LEAST 2000 J/KG.
DESPITE RELATIVELY WEAK/AMBIGUOUS LARGE SCALE FORCING ACROSS THE
REGION...CONVERGENCE ALONG BOUNDARY INTERSECTIONS...AND INTENSE
HEATING INTO THE 90S SHOULD PROVE SUFFICIENT FOR STORM INITIATION
WITHIN 1-2 HOURS. RUC FCST SOUNDINGS INDICATED THAT REMAINING
INHIBITION SHOULD BE OVERCOME AS TEMPERATURES EXCEED THE MID 90S.
TEMPERATURES ACROSS SCNTRL SD...IN WAKE OF THE WIND SHIFT...WERE
ALREADY NEARING 95F. INCREASING NWLY FLOW WITH HEIGHT ATOP WEAK
SLY/SELY NEAR SURFACE FLOW WILL RESULT IN STRONG DEEP LAYER SHEAR
SUPPORTIVE OF SUPERCELLS. STORMS TRACKING SWD ALONG RESIDUAL OUTFLOW
BOUNDARY ACROSS ECNTRL NEB WILL ENCOUNTER ENHANCED 0-3KM SRH IN THE
200-300 M2/S2 RANGE...MORE THAN ADEQUATE TO MAINTAIN STRONG
MESOCYCLONES...AND A CHANCE FOR TORNADOES. ADDITIONALLY... LARGE
HAIL AND DAMAGING WINDS ARE LIKELY WITH ANY SUPERCELLS THAT FORM.

..CARBIN.. 07/15/2004

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...FSD...OAX...ABR...GID...LBF...UNR...

41079933 41440050 41860116 42670008 43489982 44219933
44159807 43139715 41909664 41139777 

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