MESOSCALE PRECIPITATION DISCUSSION 0090
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
546 PM EDT TUE JUN 03 2014
 
AREAS AFFECTED...CNTRL NE INTO SWRN IA AND NRN MO 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 032145Z - 040345Z
 
SUMMARY...THE BEGINNING OF A POTENTIALLY HIGH IMPACT FLASH FLOOD
EVENT APPEARS TO BE UNFOLDING. 2 TO 4 INCHES OF RAINFALL IS
EXPECTED IN THE THREAT AREA BY 03Z AS CONVECTION CONTINUES TO
EXPAND ALONG AND NORTH OF A SHARPLY DEFINED WARM FRONT...WITH
LOCALLY HIGHER TOTALS.

DISCUSSION...DAYTIME HEATING HAS HELPED A HIGHLY UNSTABLE AIRMASS
TO SET UP SOUTH OF A SLOW MOVING WARM FRONT ANALYZED ESEWD ACROSS
CNTRL NE INTO SWRN IA AND NERN MO. RECENT SPC MESOANALYSES OF THIS
AIRMASS INDICATE 3000-4000 J/KG OF ML CAPE IS IN PLACE WITH KLNX
RADAR INDICATING NUMEROUS CLUSTERS OF STORMS HAVE DEVELOPED JUST
NORTH OF THE WARM FRONT WITH STORM MOTIONS GENERALLY TOWARD THE
EAST AT 20 TO 30 KTS. 

THE EXPECTATION IS FOR THE COVERAGE OF STORMS TO CONTINUE TO
INCREASE ACROSS NE/IA WHILE INDIVIDUAL CELLS TRACK TOWARD THE E OR
ESE. MEANWHILE...GLOBAL AND SHORT TERM RAP GUIDANCE SUGGESTS 850 -
700 MB INFLOW INTO THIS REGION WILL INCREASE THROUGH THE REMAINDER
OF THE EVENING FROM CURRENT VAD WIND PROFILE PLOTS OF 30-40 KTS TO
50-60 KTS SHORTLY AFTER 00Z. A CONSENSUS OF THE 12Z HI-RES
GUIDANCE HAS HIGHLIGHTED A HEAVY RAIN EVENT ACROSS THE THREAT AREA
WITH REASONABLE AGREEMENT...SEEMINGLY CAPTURED BEST BY RECENT RUNS
OF THE HRRR AND 12Z WRF4NSSL. FFG VALUES OF 1 TO 2 IN/HR AND 2 TO
3 IN/3 HR SHOULD BE MET WITH AREAS OF TRAINING CONVECTION.

OTTO

ATTN...WFO...DMX...EAX...FSD...OAX...GID...LBF...

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

LAT...LON   39709320 40709706 41399960 42230011 42669862 42659635
            42059387 40969270 39709320