MESOSCALE PRECIPITATION DISCUSSION 0388
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
307 PM EDT TUE JUN 28 2016
 
AREAS AFFECTED...SOUTHERN NY STATE...CENTRAL AND EASTERN PA... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 281910Z - 290010Z
 
SUMMARY...AN INCREASING AREA OF CONVECTION AHEAD OF A COLD FRONT
COULD START TRAINING...RESULTING IN HOURLY RAINFALL RATES NEAR 2
INCHES...WHICH COULD RESULT IN FLASH FLOODING INTO THIS EVENING.  

DISCUSSION...REGIONAL RADARS SHOWED AN INCREASING IN CONVECTION
AHEAD OF A COLD FRONT STRETCHED ACROSS EASTERN NY STATE INTO
CENTRAL PA. THE CONVECTION WAS DEVELOPING IN AN AXIS OF 1000-15000
MLCAPE...WHERE THE BLENDED TPW PRODUCT SHOWED PRECIPITABLE WATER
VALUES NEAR 1.25 INCHES. THE KENX RADAR SHOWED HOURLY RAINFALL
RATES BETWEEN 1.75 AND 2.00 INCHES WITH THE NEWLY DEVELOPED
CONVECTION...WITH LOCALLY HIGHER AMOUNTS WITH NEARLY STATIONARY
STORMS WEST OF KALB. 

CONVECTION IS EXPECTED TO EXPAND IN COVERAGE AHEAD OF THE COLD
FRONT FROM EASTERN NY STATE INTO MUCH OF EASTERN PA...AS THE LOW
LEVEL CONVERGENT FLOW FOCUSES ALONG THE IN SITU INSTABILITY AND
MOISTURE. THERE IS A MULTI MODEL SIGNAL (LED BY THE 12Z WRF
ARW/LATEST HRRR) FOR LOCAL 2-4 INCH RAINFALL AMOUNTS... ESPECIALLY
WHERE TRAINING OCCURS. ONE AND THREE HOUR FLASH FLOOD GUIDANCE
VALUES GENERALLY RANGE BETWEEN 2 AND 3 INCHES...SO FLASH FLOODING
IS ONLY CONSIDERED POSSIBLE.

HAYES

ATTN...WFO...ALY...BGM...BTV...CTP...OKX...PHI...

ATTN...RFC...MARFC...NERFC...

LAT...LON   43997417 43707333 41977379 41317504 39937610 
            39907671 41027678 43537484