[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 210021
SWOMCD
SPC MCD 210020 
NDZ000-SDZ000-210145-

MESOSCALE DISCUSSION 1745
NWS STORM PREDICTION CENTER NORMAN OK
0720 PM CDT TUE JUL 20 2004

AREAS AFFECTED...CENTRAL AND ERN ND...NRN SD

CONCERNING...SEVERE THUNDERSTORM WATCH 658...

VALID 210020Z - 210145Z

SURFACE ANALYSIS SHOWS COOL TEMPERATURES IN THE 70S AND LOWER 80S F
OVER ERN ND AND NWRN MN.  THIS HAS DECREASED SURFACE BASED
INSTABILITY IN THESE AREAS INTO THE 1000-2000 J/KG RANGE.  MUCH
HIGHER INSTABILITY REMAINS TO THE W WITHIN N-S AXIS WITH 2000-3500
MLCAPE FROM BIS SWD INTO SD.

LOW LEVEL WARM ADVECTION AHEAD OF SURFACE COLD FRONT IS NOT
PARTICULARLY STRONG...WITH ONLY 15 KTS OF SLY FLOW AT 850 MB NOTED
ON AREA PROFILERS.  THEREFORE...QUESTION REMAINS WHETHER OR NOT
STORMS CAN SUSTAIN THEMSELVES VERY FAR E WHERE MORE SUBSTANTIAL CIN
REMAINS AND WILL BE INCREASING WITH TIME AS BOUNDARY LAYER COOLS. 

CONVECTIVE TRENDS WILL CONTINUE TO BE MONITORED...HOWEVER...CHANCES
ARE THAT STORMS WILL BEGIN TO WEAKEN ONCE THEY EXIT WW
658...ALTHOUGH ISOLATED SEVERE HAIL / WIND WILL CERTAINLY REMAIN
POSSIBLE.

..JEWELL.. 07/21/2004

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

ATTN...WFO...FGF...ABR...BIS...UNR...

44980343 45820259 47740232 49010236 49019813 46469878
44979926 

WWWW