[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 121927
SWOMCD
SPC MCD 121927 
MNZ000-SDZ000-122130-

MESOSCALE DISCUSSION 2176
NWS STORM PREDICTION CENTER NORMAN OK
0227 PM CDT MON SEP 12 2005

AREAS AFFECTED...CENTRAL/E-CENTRAL SD AND SWRN MN

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 121927Z - 122130Z

POTENTIAL EXISTS FOR A FEW STORMS WITH LARGE HAIL ACROSS
CENTRAL/NERN SD DURING THE REMAINDER OF THIS AFTERNOON. SURFACE
BOUNDARY ACROSS ERN SD INTO SWRN MN IS BEING MONITORED FOR POSSIBLE
NEW TSTM DEVELOPMENT...ALTHOUGH POTENTIAL INITIATION APPEARS MOST
LIKELY TOWARD THIS EVENING.

AT 19Z...WEAK CYCLONE CENTER HAS DEVELOPED ALONG QUASI-STATIONARY
SURFACE FRONT BETWEEN PIERRE AND CHAMBERLAIN SD. BOUNDARY LAYER HAS
BECOME MODERATELY UNSTABLE JUST EAST AND SOUTH OF THIS
REGION...WHERE FRONTAL BOUNDARY IS MOVING SLOWLY NWD AS A WARM FRONT
THROUGH E-CENTRAL SD AND SWRN MN. MLCAPE VALUES OF 1500-2500 J/KG
ARE PRESENT...WITH SFC TEMPERATURES IN THE LOW 80S AND DEWPOINTS
NEAR 70F.

SURFACE-BASED INITIATION IS SOMEWHAT UNCERTAIN ACROSS E-CENTRAL SD.
ONGOING THUNDERSTORMS ACROSS NRN SD AND NEAR PHP ARE ASSOCIATED WITH
ELEVATED CAPE OF 1000 J/KG OR SO PER RAP 18Z SOUNDING. A WEAK
SHORTWAVE TROUGH IN ADVANCE OF MAIN UPPER LOW OVER SWRN WY MAY ALSO
BE CONTRIBUTING TO UVV IN THIS AREA NORTH OF THE FRONT AND SURFACE
LOW.

ONGOING STORMS SHOULD TRACK GENERALLY NEWD TOWARD N-CENTRAL/NERN SD
WITH AN ISOLATED THREAT OF LARGE HAIL WITH LONGER-LIVED CELLS. NEAR
THE SURFACE LOW...THICKENING LOW CLOUDS AND ABSENCE OF DEEP-LAYER
FORCING DURING THE NEXT 1-3 HOURS MAY PRECLUDE DEVELOPMENT.
HOWEVER...WV IMAGERY INDICATES UPPER JET EXIT REGION MOVING NEWD
THROUGH WRN KS AT THE PRESENT TIME. THIS MAY AID IN INITIATION
ACROSS THE WARM SECTOR DURING THE EVENING HOURS. TRENDS WILL BE
CLOSELY MONITORED ACROSS CENTRAL/ERN SD AND SWRN MN DURING THE NEXT
SEVERAL HOURS.

..BANACOS.. 09/12/2005

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

ATTN...WFO...MPX...FSD...ABR...UNR...

43479846 43830115 45480103 45529704 45429523 44559467
43759493 43609567 43539719 

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