[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 162349
SWOMCD
SPC MCD 162349 
IAZ000-170145-

MESOSCALE DISCUSSION 2021
NWS STORM PREDICTION CENTER NORMAN OK
0649 PM CDT MON AUG 16 2004

AREAS AFFECTED...IA

CONCERNING...SEVERE THUNDERSTORM WATCH 755...

VALID 162349Z - 170145Z

CONTINUE WW.

VIGOROUS THUNDERSTORM ACTIVITY IS ONGOING.  MOST INTENSE STORMS HAVE
BEEN SOUTH OF MASON CITY...WHERE LOW-LEVEL WARM ADVECTION WAS
MAXIMIZED ALONG THERMAL GRADIENT TO THE EAST SOUTHEAST OF SURFACE
LOW...NOW NORTH OF SIOUX CITY. HOWEVER...MORE RECENT CONVECTIVE
DEVELOPMENT HAS TAKEN PLACE UPSTREAM TOWARD SURFACE LOW...SUPPORTED
BY FORCED ASCENT OF BOUNDARY LAYER WITH MEAN MIXED LAYER CAPE AROUND
2000 J/KG.  FURTHER INCREASE/INTENSIFICATION OF THUNDERSTORMS
APPEARS LIKELY IN THIS ENVIRONMENT ACROSS NORTHWEST/CENTRAL IOWA
DURING THE NEXT COUPLE OF HOURS.  NORTHWESTERLY MID-LEVEL FLOW
REGIME AND ASSOCIATED SHEAR ARE RATHER WEAK...BUT THERMODYNAMIC
ENVIRONMENT WILL REMAIN SUPPORTIVE OF LARGE HAIL/DAMAGING WIND GUSTS
INTO THE EVENING HOURS.

..KERR.. 08/16/2004

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

ATTN...WFO...DMX...FSD...

42879538 43149436 42869282 42249258 41739233 41399288
41269381 41579464 42049525 42529588 

WWWW