[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 161610
SWOMCD
SPC MCD 161610 
WIZ000-IAZ000-161815-

MESOSCALE DISCUSSION 1301
NWS STORM PREDICTION CENTER NORMAN OK
1110 AM CDT WED JUN 16 2004

AREAS AFFECTED...IA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL...HEAVY RAINFALL 

VALID 161610Z - 161815Z

TSTM CLUSTERS HAVE RECENTLY INTENSIFIED ACROSS NWRN IA AND WILL
LIKELY EXPAND ENEWD OVER THE NEXT FEW HOURS.  LARGE HAIL... DAMAGING
WINDS AND VERY HEAVY RAINFALL CAN BE EXPECTED. A WW MAY BE
REQUIRED.

SURFACE MESOANALYSIS DEPICTS A COMPACT LOW BETWEEN SIOUX CITY AND
OMAHA WITH A TRAILING SURFACE TROUGH SWD ALONG THE MO RVR AND AN E-W
BOUNDARY INTO SWRN WI. SURFACE LOW APPEARS TO BE DEEPENING GIVEN
RECENT STRENGTHENING AGEOSTROPHIC FLOW ACROSS NWRN IA. ENHANCED
MOISTURE CONVERGENCE HAS AIDED IN RAPIDLY DEVELOPING TSTM CLUSTER
OVER NWRN IA WHERE MUCAPE VALUES WERE 1000-2000 J/KG. CURRENTLY...
THESE TSTMS APPEAR TO BE MAINLY ELEVATED.

VSBL SATELLITE SUGGESTS DOWNSTREAM AIR MASS WILL DESTABILIZE WITH
THINNING HIGH CLOUD CANOPY THE NEXT FEW HOURS. AS THE E-W BOUNDARY
BECOMES STRONGER INTO NCNTRL/NERN IA WITHIN THE UNSTABLE
ENVIRONMENT/WEAKENING CINH...TSTMS SHOULD EXPAND EWD INTO THESE
REGIONS.  OTHER TSTMS ARE APT TO DEVELOP SWD ALONG THE SURFACE
TROUGH TOWARD THE DES MOINES AREA.

REGION RESIDES ALONG THE SRN PERIPHERY OF STRONG H5 FLOW AND DEEP
LAYER SHEAR IS ONLY MARGINALLY SUPPORTIVE OF SUPERCELLS. BUT...
STRONG-SEVERE MULTICELLS WILL REMAIN POSSIBLE WITH LARGE HAIL AND
DAMAGING WINDS THE PRIMARY THREATS.

GIVEN HIGH PRECIPITABLE WATER VALUES AND SLOW MOVEMENT OF THE
LOW...VERY HEAVY RAINFALL CAN BE EXPECTED.  HEAVIEST CORRIDOR OF
RAIN SHOULD OCCUR IN A 70 MILE WIDE AXIS EXTENDING FROM 50 WSW FORT
DODGE TO 35 SW WATERLOO TO 25 NW OF DUBUQUE.

..RACY.. 06/16/2004

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

ATTN...WFO...DVN...ARX...DMX...FSD...OAX...

40669485 41429523 42219555 42899563 43149478 43319425
43379370 43459295 43429233 43449165 43339139 42889116
42499086 41609102 40919161 

WWWW