MESOSCALE PRECIPITATION DISCUSSION 0138...CORRECTED
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
759 PM EDT WED JUN 18 2014
 
CORRECTED FOR TYPO

AREAS AFFECTED...EASTERN DAKOTAS AND SOUTHWEST MN 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 182355Z - 190555Z
 
SUMMARY...A BURGEONING THUNDERSTORM COMPLEX ACROSS SD AND SOUTHERN
ND IS EXPECTED TO EXPAND EASTWARD WHILE MOVING SLOWLY
NORTHEASTWARD.  SEVERAL INSTANCES OF FLASH FLOODING ARE POSSIBLE
IN THIS REGION.

DISCUSSION...RADAR AND SATELLITE IMAGERY COMBINED WITH THE RECENT
RAP 700 HPA TEMPERATURE GUIDANCE INDICATE THAT THE MID-LEVEL CAP
IS ERODING ACROSS SD AND SOUTHERN MN AS SHORTWAVES ROTATING AROUND
THE MT CYCLONE AND THE TROUGH ACROSS EASTERN CANADA CHIP AWAY AT
ITS NORTHERN PORTION.  RAINFALL RATES HAVE APPROACHED 2" AN HOUR
WITH THIS ACTIVITY THIS AFTERNOON AND EVENING, FOCUSED MAINLY NEAR
AND ALONG A TROWAL.  CAPES WITHIN THIS REGION ARE 1000-2000 J/KG,
WITH UPSTREAM CAPES ACROSS SOUTHEAST SD AND WESTERN IA AS HIGH AS
6000-7000 J/KG.

WITH TIME, INFLOW AT 850 HPA INCREASES ACROSS THE REGION WHICH
SHOULD EXPAND ACTIVITY EASTWARD ALONG THE SYSTEM'S
STATIONARY/SLOW-MOVING WARM FRONT WITH TIME.  PRECIPITABLE WATER
VALUES ARE EXPECTED TO CLIMB FURTHER, TOWARDS 2", WHICH IS NEAR
THE 99TH PERCENTILE FOR MID-JUNE.  RAIN RATES COULD REACH 2.5" AN
HOUR IN STRONGER STORMS.  THE MESOSCALE QPF GUIDANCE SHOWS A
MODERATELY STRONG SIGNAL FOR EXCESSIVE RAINFALL IN THIS REGIONS,
INDICATING THAT LOCAL AMOUNTS OF 3-5" ARE POSSIBLE.  THIS WOULD
EXCEED THE RELATIVELY HIGHER FLASH FLOOD GUIDANCE VALUES ACROSS
EASTERN SD AND SOUTHEAST ND.  SEVERAL INSTANCES OF FLASH FLOODING
ARE POSSIBLE IN THIS REGION.

ROTH

ATTN...WFO...MPX...FGF...FSD...ABR...BIS...

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

LAT...LON   43529765 43709883 43819948 45180068 46670092 47759926
            47329759 46029626 44559514 43719470 43489532 43499660
            43529765