MESOSCALE PRECIPITATION DISCUSSION 0222
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
938 PM EDT MON JUN 15 2015
 
AREAS AFFECTED...CENTRAL TO EASTERN OH/WESTERN PA... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 160138Z - 160638Z
 
SUMMARY...UPSTREAM CONVECTION FROM THE UPPER GREAT LAKES CONTINUES
TO DROP HEAVY RAINFALL ACROSS AREAS OF OH AND INTO WESTERN PA.
SIGNIFICANTLY LOW FFG VALUES SUGGESTS ANY ADDITIONAL PRECIPITATION
OVER THE REGION WILL ENHANCE THE RISK FOR FLASH FLOODING.

DISCUSSION...WITH A BROAD LOW/MID-LEVEL ANTICYCLONE ANCHORING THE
SOUTHEASTERN U.S...CONVECTION CONTINUES TO STREAM EASTWARD ABOVE
THE EXPANSIVE RIDGE. MUCH OF THE HEAVY PRECIPITATION AFFECTING THE
UPPER GREAT LAKES REGION IS EXPECTED TO MIGRATE EASTWARD TOWARD
AREAS WITH VERY LOW FFG VALUES. THIS THEME IS FORECAST TO CONTINUE
GIVEN SUFFICIENT BUOYANCY WITHOUT MUCH CAPPING AS SUGGESTED BY THE
GUIDANCE. THERMODYNAMIC PROFILES ARE QUITE IMPRESSIVE PER THE 00Z
RAOB FROM PIT. DEEP-LAYERED WESTERLY UNIDIRECTIONAL FLOW IS
PRESENT IN CONJUNCTION WITH A TALL/SKINNY CAPE PROFILE CONSISTING
OF VALUES ABOVE 1800 J/KG. MODIFYING THE LOW-LEVEL TEMPERATURES
FOR NOCTURAL COOLING STILL IMPLIES CAPES IN THE 1000 TO 1500 J/KG
RANGE WITH NO INHIBITION. THE TROPOSPHERIC WIND STRUCTURE IN PLACE
FAVORS TRAINING/REPEAT CONVECTION ACROSS THE REGION. 00Z RAP
FORECAST CORFIDI VECTORS ARE MINIMIZED THUS SUPPORTING THIS NOTION.

THE LATEST 00Z HRRR HAS A REASONABLE DEPICTION OF THE ONGOING
CONVECTIVE ACTIVITY. MANY OF THE CONVECTION-ALLOWING MODELS FROM
THE 12Z CYCLE WERE TOO FAR NORTH RELATIVE TO THE RADAR/SATELLITE
TRENDS. CONSIDERING THE 00Z HRRR AT FACE VALUE...EXPECT ANOTHER 1
TO 2 INCHES OF RAINFALL THROUGH 06Z ACROSS THE MPD AREA WITH
ISOLATED HIGHER AMOUNTS POSSIBLE. FLASH FLOODING IS POSSIBLE
ACROSS THE ENTIRE REGION WHILE BEING MORE LIKELY IN AREAS WHERE
FFG VALUES ARE MINIMIZED.



RUBIN-OSTER

ATTN...WFO...CLE...CTP...ILN...PBZ...RLX...

ATTN...RFC...MARFC...OHRFC...

LAT...LON   41748020 41497904 40987842 40477843 40147872 
            39957917 40048009 39978122 39628252 40078320 
            41048297 41598164 
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