MESOSCALE PRECIPITATION DISCUSSION 0161...CORRECTED
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
110 PM EDT SAT JUN 28 2014
 
CORRECTED FOR TYPO IN FIRST DISCUSSION PARAGRAPH

AREAS AFFECTED...CENTRAL ND 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 281658Z - 282258Z
 
SUMMARY...RAINFALL RATES OF UP TO 2" AN HOUR WITHIN A TRAINING
BAND OF MODERATE CONVECTION ARE POSSIBLE OVER SATURATING SOILS
ACROSS CENTRAL ND.  A FEW SPOTS OF FLASH FLOODING ARE POSSIBLE IN
THIS REGION.

DISCUSSION...A COMPLEX SURFACE ENVIRONMENT IS MARKED BY BAROCLINIC
ZONES ASSOCIATED WITH A DEEP CYCLONE ACROSS SOUTHERN SD, A DRAPING
STATIONARY FRONT ALONG ITS PATH IN CENTRAL ND, AND WEAK SURFACE
CONVERGENCE ACROSS SOUTHWEST MN AND NORTHWEST IA.  PRECIPITABLE
WATER VALUES AROUND 1.75" ARE WITHIN THE REGION, WHICH ARE NEAR
THE 95TH PERCENTILE FOR LATE JUNE.  INFLOW AT 850-700 HPA IS IN
THE 30-40 KT RANGE -- CLOSE TO THE 850-400 HPA MEAN WINDS SHOWN BY
THE 12Z NAM -- BRINGING 0-3 KM SHEAR TO 25+ KTS.  CAPE VALUES OF
1000-2000 J/KG ARE OFFSET TO THE EAST WITHIN THE SYSTEM'S INFLOW
ACROSS NORTHEAST SD, EASTERN ND, AND MUCH OF MN.  RAINFALL RATES
SO FAR HAVE BEEN MORE INDICATIVE OF A FLOOD EVENT THAN A FLASH
FLOOD EVENT, WITH REPORTS OF 2-4" OVER SEVERAL HOURS ACROSS
PORTIONS OF WESTERN AND CENTRAL ND.

OTHER THAN THE MAIN CYCLONE, A SECOND UPSTREAM SHORTWAVE MOVING
NORTHWARD THROUGH SD COULD SPUR NEW DEVELOPMENT ACROSS ND OVER THE
NEXT SEVERAL HOURS PER COORDINATION WITH SAB/NESDIS.  DUE TO
DAYTIME HEATING, CAPE VALUES WITHIN ITS INFLOW SHOULD INCREASE
SOME MORE, WHICH COULD DRIVE UP PRECIPITATION RATES TOWARDS 2" AN
HOUR.  THE MOST RECENT MESOSCALE GUIDANCE SHOWS A MODERATE SIGNAL
FOR LOCAL AMOUNTS OF 2-3" FALLING OVER THE NEXT SIX HOURS.  THIS
IS A BORDERLINE SITUATION FOR FLASH FLOODING; A QUICK 2-3" LOCALLY
COULD CAUSE A FEW SPOTS OF FLASH FLOODING.

ROTH

ATTN...WFO...FGF...ABR...BIS...

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

LAT...LON   47300161 48600184 49050135 49069990 49069925 48549918
            47649955 46490014 45870061 46110138 47300161