MESOSCALE PRECIPITATION DISCUSSION 0127...CORRECTION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
124 PM EDT MON JUN 16 2014

CORRECTED FOR TYPOS
 
AREAS AFFECTED...EASTERN DAKOTAS, NORTHWEST IA, WESTERN MN 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 161719Z - 162319Z
 
SUMMARY...A PAIR OF CONVECTIVE COMPLEXES WITH EXPANDING COOL TOPS
ARE EXPECTED TO MERGE ACROSS SOUTHWEST MN OVER THE NEXT COUPLE
HOURS, THEN PROGRESS EAST-NORTHEAST AT 25 KTS.  DUE TO SATURATED
SOILS IN THE REGION, SEVERAL INSTANCES OF FLASH FLOODING ARE
POSSIBLE.

DISCUSSION...A COLD POOL IS DEVELOPING ACROSS THE DAKOTAS, CAUSED
BY A CONVECTIVE CLUSTER WHICH HAS BEEN MOVING EASTWARD ACROSS SD. 
ANOTHER CONVECTIVE MASS FROM EASTERN NE IS MOVING INTO WESTERN IA,
WITH NEW SCATTERED THUNDERSTORMS FORMING BETWEEN THE TWO.  WIND
SHEAR IN THE 0-3 KM LAYER OF 30 KTS COMBINED WITH AMBIENT CAPES OF
2000-2500 J/KG ARE SUFFICIENT FOR THE WET MULTI-CELL ENVIRONMENT,
AND 0-6 KM BULK SHEAR IS SUFFICIENT FOR ORGANIZED CONVECTION IN
GENERAL.

THE MOST RECENT MESOSCALE GUIDANCE IS NEARLY UNANIMOUS IN SHOWING
HEAVY RAINS CENTERED UPON SOUTHWEST AND SOUTH-CENTRAL MN, NEAR THE
EXPECTED SITE OF THE CONVECTIVE COMPLEX MERGER, WHICH SHOULD FORM
AN MCC.  OTHER SCATTERED THUNDERSTORM ACTIVITY IS EXPECTED TO MOVE
ACROSS A VERY SATURATED REGION NEAR THE MN/ND BORDER.  HIGH
RAINFALL RATES ON THE ORDER OF 2" AN HOUR ARE ANTICIPATED OVER
SATURATED AREAS WHERE FLASH FLOOD GUIDANCE IS GENERALLY 1.5" IN
THREE HOURS.  USING THE MESOSCALE GUIDANCE AS A CUE, A QUICK 3-5"
IS EXPECTED LOCALLY.  THE SYSTEM AS A WHOLE IS EXPECTED TO
CONTINUE MOVING ROUGHLY 25 KTS TO THE EAST-NORTHEAST, WHICH SHOULD
LIMIT THE EXTENT OF THE FLASH FLOODING.  SEVERAL INSTANCES OF
FLASH FLOODING ARE ANTICIPATED.

ROTH

ATTN...WFO...MPX...DMX...FGF...FSD...OAX...ABR...

ATTN...RFC...MBRFC...NCRFC...

LAT...LON   43799346 42929420 42789444 42199594 42769758 43559859
            44689809 46179773 48929744 48809659 46569491 44999377
            43799346