MESOSCALE PRECIPITATION DISCUSSION 0279
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1113 AM EDT SAT AUG 16 2014
 
AREAS AFFECTED...CENTRAL AND EASTERN ND...NE SOUTH DAKOTA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 161449Z - 161749Z
 
SUMMARY...A SLOW-MOVING COMPLEX OF THUNDERSTORMS WITH HOURLY RAIN
RATES ONE TO THREE INCHES PER HOUR IS EXPECTED TO PERSIST INTO THE
EARLY AFTERNOON HOURS.  FLASH FLOODING REMAINS POSSIBLE.

DISCUSSION...A MID-LEVEL CIRCULATION HAS BEEN MOVING EASTWARD
ACROSS ND VERY SLOWLY AT ONLY 5 TO 10 KTS, ACCOMPANIED BY
THUNDERSTORMS WITH COLD CLOUD TOPS AND HEAVY RAINFALL.  DOPPLER
RADAR RAINFALL ESTIMATES ARE ON THE ORDER OF 2 TO 4 INCHES IN
CENTRAL ND THIS MORNING, WITH SOME REPORTS OF RAINFALL RATES
EXCEEDING 2 INCHES PER HOUR.  THE COMBINATION OF PW VALUES NEAR
1.75 INCHES, 1000 J/KG CAPE, AND 25KT 850MB INFLOW INTO THE
THUNDERSTORM AREA IS FAVORABLE FOR EXCESSIVE RAINFALL AND
POTENTIAL FLASH FLOODING. 

COLLABORATION WITH SAB/NESDIS SUGGESTS THIS THUNDERSTORM AREA
SHOULD PERSIST UNTIL THE EARLY AFTERNOON HOURS. THE SYSTEM IS
MOVING INTO AN AREA WITH HIGHER MUCAPE TO THE EAST, WHICH ALSO
SUGGESTS THE STORMS COULD MAINTAIN THEMSELVES FOR A FEW MORE HOURS
BEFORE GRADUALLY DIMISHING.  HOURLY RAINFALL RATES UP TO 2 INCHES
PER HOUR ARE POSSIBLE WITH THE MAIN CONVECTIVE BAND OF
THUNDERSTORMS.  ANOTHER AREA OF STRATIFROM RAIN WITH EMBEDDED
CONVECTIVE ELEMENTS IS EXPECTED TO THE NORTH AND WEST OF THE MAIN
CONVECTIVE LINE.  THIS WILL PRODUCE AN ADDITIONAL QUARTER TO ONE
INCH OF RAINFALL OVER AREAS THAT HAVE ALREADY SEEN HEAVY RAINFALL.

HAMRICK

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

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

LAT...LON   47670200 48760165 48969971 48499820 46959754 45349767
            44769884 45070035 46360136 47670200