[MCD] SWOMCD

Sat Nov 12 21:37:01 UTC 2005

ACUS11 KWNS 122135
SWOMCD
SPC MCD 122135 
IAZ000-MNZ000-SDZ000-122300-

MESOSCALE DISCUSSION 2405
NWS STORM PREDICTION CENTER NORMAN OK
0335 PM CST SAT NOV 12 2005

AREAS AFFECTED...SE SD/SW MN...WRN IA

CONCERNING...TORNADO WATCH 858...

VALID 122135Z - 122300Z

CONTINUE REMAINING VALID PORTION OF WW.  POTENTIAL FOR ISOLATED
TORNADOES IS EXPECTED TO INCREASE NEXT FEW HOURS.

CONVECTIVE DEVELOPMENT IS ONGOING...FOCUSED NEAR SURFACE LOW
CENTER...NOW JUST TO THE SOUTHWEST OF SIOUX FALLS...AND ALONG DRY
LINE WHICH HAS SURGED EAST OF THE MISSOURI RIVER INTO WESTERN IOWA. 
UPSTREAM COLD FRONT APPEARS LIKELY TO MERGE INTO DRY LINE WITHIN THE
NEXT HOUR OR TWO...AS SURFACE LOW CONTINUES TO DEEPEN AND SLOWLY
MIGRATE NORTHEASTWARD. AS THIS OCCURS...BROKEN LINE OF CONVECTION
IS EXPECTED TO SOLIDIFY NEAR/NORTHWEST OF DES MOINES THROUGH THE
VICINITY OF FORT DODGE INTO AREAS EAST OF SPENCER.  DAMAGING WIND
POTENTIAL SHOULD INCREASE AS HIGHER MOMENTUM ALOFT IS TRANSFERRED TO
THE SURFACE.  STRONG LOW-LEVEL SHEAR WILL CONTINUE TO SUPPORT
POTENTIAL FOR ISOLATED TORNADOES IN STRONGER CELLS WITHIN DEVELOPING
LINE.  PERHAPS SOMEWHAT BETTER TORNADO POTENTIAL WILL EXIST WHERE
AMBIENT VERTICAL VORTICITY IS ALREADY BECOMING MAXIMIZED...IN THE
VICINITY OF DEEPENING SURFACE LOW...NEAR/EAST OF SIOUX FALLS THROUGH
00Z.

..KERR.. 11/12/2005

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

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

43679748 44299686 44309545 43889477 42769386 42109349
41309369 41069438 41949488 42719598 

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