MESOSCALE PRECIPITATION DISCUSSION 0346
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
627 PM EDT SUN JUL 12 2015
 
AREAS AFFECTED...RED RIVER VALLEY INTO MINNESOTA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 122225Z - 130300Z
 
SUMMARY...A THREAT FOR FLASH FLOODING WILL INCREASE THROUGH THE
REMAINDER OF THE EVENING THROUGH ABOUT 02Z FOR PORTIONS OF THE RED
RIVER VALLEY INTO MINNESOTA. BEYOND 02Z...EXPECTED FORWARD
PROPAGATION OF CONVECTION SHOULD DIMINISH THE FLASH FLOOD THREAT.

DISCUSSION...22Z OBSERVATIONS PLACED A SURFACE LOW ALONG THE NORTH
DAKOTA/SOUTH DAKOTA BORDER...JUST NORTH OF 8D3...WITH A WEAK
DRYLINE/TROUGH EXTENDING SSW ACROSS ERN SOUTH DAKOTA. A WELL
DEFINED NW TO SE ORIENTED STATIONARY FRONT EXTENDED FROM THE LOW
ACROSS ERN NORTH DAKIOTA AND SRN MINNESOTA. SURFACE DEWPOINTS IN
THE WARM SECTOR WERE VERY MOIST...WITH VALUES IN THE UPPER 70S TO
LOW 80S...CONTRIBUTING TO ESTIMATED PRECIPITABLE WATER VALUES
BETWEEN 1.50 AND 1.75 INCHES...BASED ON A MODIFIED 20Z SOUNDING
FROM MPX.

WHILE THE MODE IS PRIMARILY SEVERE AT THIS TIME...THERE ARE SOME
INDICATIONS FOR A SOMEWHAT BRIEF FLASH FLOOD THREAT ACROSS
PORTIONS OF CNTRL AND SRN MINNESOTA AS MOISTURE STREAMS AHEAD OF
THE SURFACE DRYLINE/TROUGH...ACROSS THE STATIONARY FRONT INTO AN
ONGOING CLUSTER OF STORMS IN WILKIN...OTTER TAIL AND GRANT
COUNTIES...LOCATED IN W-CNTRL MINNESOTA. THE LEFT EXIT REGION OF A
WEST-EAST ORIENTED 100 KT JET AT 250 MB ACROSS SOUTH DAKOTA MAY
ALSO PROVIDE SOME ADDED LIFT IN CONJUNCTION WITH EXTREME
INSTABILITY OVER THE REGION.

CURRENT STORM MOTIONS ARE GENEARLLY ENE AT 20-30 KTS BUT
REGENERATION OF CONVECTION ON THE NORTHWEST SIDE OF ONGOING
ACTIVITY IN W-CNTRL MINNESOTA APPEARS LIKELY OVER THE NEXT 3-4
HOURS BEFORE MANY CONVECTION ALLOWING MODELS FORM A FORWARD
PROPAGATING MCS TOWARD THE SOUTHEAST. THE 19Z AND 20Z
HRRR_EXPERIMENTAL WAS THOUGHT TO BE HAVING THE BEST HANDLE ON
ACTIVITY WITH POTENTIAL FOR A QUICK 3-4 INCHES BEFORE 02Z.

OTTO

ATTN...WFO...ABR...DLH...FGF...MPX...

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

LAT...LON   47239623 47159542 46459420 44549329 44219511 
            45879685 46789696