MESOSCALE PRECIPITATION DISCUSSION 0314
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
434 PM EDT MON JUL 06 2015
 
AREAS AFFECTED...SOUTEHRN IOWA...NORTHERN AND WESTERN
MISSOURI...EASTERN KANSAS 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 062033Z - 070233Z
 
SUMMARY...VERY STRONG/EFFICIENT RAINFALL PRODUCING LINEAR MCS
DEVELOPING AHEAD OF COLD FRONT LIKELY TO PRODUCE RAIN RATES IN
EXCESS OF 2"/HR TO LEAD TO LIKELY FLASH FLOODING. 

DISCUSSION...VERY STRONG WELL DEFINED UPPER LEVEL TROF SEEN IN WV
ACROSS NORTHERN PLAINS INTO UPPER MISSISSIPPI VALLEY HAS A WELL
DEFINED TAIL END VORT MAX SHIFTING EASTWARD ALONG THE CENTRAL
NEBRASKA/KANSAS BOARDER.  A SECONDARY SHORTWAVE EXITING NEW MEXICO
ALLOWS FOR SHORTWAVE RIDGING ACROSS COLORADO INTO WESTERN KANSAS
TO FLATTEN OUT ACROSS AND CONNECT UP ALONG THE E-W CORRIDOR. THIS
ALLOWS FOR ADDITIONAL DIVERGENCE/DIFFLUENCE OVER NORTHEAST KANSAS
INTO NORTHWEST MISSOURI FOR GOOD UPPER LEVEL EVACUATION TO
STRENGTHEN UPDRAFTS. IN THE LOWER LEVELS...A WEAK INFLECTION ALONG
THE COLD FRONT CAN BE ANALYZED WITH SOME WEAK BACKED SURFACE FLOWS
ACROSS EASTERN KANSAS ...ALLOWING FOR ADDITIONAL SOUTHERLY
TRANSPORT OF 20-25KT LOW LEVEL FLOW INTO CENTRAL AND EASTERN
KANSAS MAXIMIZING ALONG WELL DEFINED SURFACE FRONT WITH  STRONG
DEEP MOISTURE CONVERGENCE FROM JUST NORTH OF ICT TOWARD STJ. GIVEN
HIGH INSTABILITIES AS SEEN BY RAP ANALYSIS SBCAPES IN THE
4000-4500 J/KG RANGE VERY STRONG CONVECTIVE GROWTH HAS ALREADY
BEGUN (PLEASE SEE RECENT SPENES FOR ADDITIONAL DETAILS) WITH TOPS
TO MID -70C.  COINCIDENT DEEP MOISTURE POOLED IN THE SURFACE
INFLECTION ON THE FRONT IS REPRESENTED BY TOTAL PWATS WELL OVER 2"
AND FORECAST TO CONTINUE TO INCREASE WITH CONVECTIVE
OVERTURNING...THIS WILL ALLOW FOR INCREASING RAINFALL EFFICIENCY
WITH RATES OF 2-2.5" LIKELY. ISOLATED OCCASIONAL  3+/HR RATES ARE
POSSIBLE WITH STORM SCALE MERGERS/INFLECTIONS AS THE QLCS MOVES
EAST.  

WV LOOP ALSO SHOWS THE DOWNSTREAM RIDGE IS EXTREMELY AMPLIFIED AND
NARROW WITH TURNING TO SOUTHERLY AND EVEN SOUTH-SOUTHWESTERLY FROM
THE BASE OF LAKE MICHIGAN BACK TOWARD NORTHWEST ARKANSAS.  THIS
WILL ALLOW FOR THE COLD FRONT/CELLS TO EVENTUALLY SLOW IN FORWARD
PROGRESS BY 00Z-02Z ALLOWING FOR INCREASED TOTALS PARTICULARLY
OVER WESTERN MISSOURI TOWARD THE KANSAS CITY METRO BACK INTO
EAST-SOUTHEAST KANSAS NORTHERN FLINT HILLS AND POINTS EAST. THIS
WILL LIKELY INCREASED MOISTURE CONVERGENCE DUE TO MORE FAVORABLE
INTERSECTION WITH THE LOW LEVEL JET IS ALSO LIKELY.  THIS SCENARIO
OF TRACKING THE BEST INFLECTION ALONG THE FRONT AND MAXIMIZED
CONVERGENCE IS REPRESENTED WELL BY THE ARW/NMMB AND THEIR PARALLEL
RUNS ALONG WITH THE GEM REGIONAL MODEL... WITH SUGGESTIONS OF
TOTALS IN EXCESS OF 4-5" WITHIN THE NEXT 6 HOURS...LEADING TO
LIKELY FLASH FLOODING CONDITIONS. BROADER 2-4" ACROSS EXTREME
SOUTHERN IOWA/NORTHERN MISSOURI SHOULD BE LIMITED IN NORTHWARD
EXTENT GIVEN THE ENVIRONMENT BEING WORKED OVER A BIT MORE FROM
EARLY MORNING ROUND IN CENTRAL IOWA AND WEAKER SHORTWAVE RIDGING
ASSOCIATED WITH THE EASTWARD MOVEMENT OF THE VORTICITY LOBE AT THE
BASE OF THE TROF.  THOUGH FLASH FLOOD GUIDANCE IN THE REGION IS
MODERATELY HIGH (1.5-2" IN 1HRS)...THE INTENSITY OF THE RATES WILL
LIKELY EXCEED THEM QUICKLY ESPECIALLY OVER THE URBAN CORRIDOR THE
HIGHEST TOTALS ARE LIKELY TO TRAVERSE.   

GALLINA

ATTN...WFO...DDC...DMX...DVN...EAX...ICT...LSX...OAX...SGF...
TOP...

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

LAT...LON   41309160 39869183 37899390 37159642 37329852 
            38589757 39619689 40879451 41269320