MESOSCALE PRECIPITATION DISCUSSION 0390
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
532 PM EDT TUE JUN 28 2016
 
AREAS AFFECTED...NORTHEAST NY INTO NORTHERN NEW ENGLAND 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY 
 
VALID 282130Z - 290330Z
 
SUMMARY...CONVECTION TRAINING ALONG AND AHEAD OF A COLD FRONT
MOVING SLOWLY ACROSS NORTHEAST NY AND NORTHERN NEW ENGLAND IS
EXPECTED TO RESULT IN FLASH FLOODING... ESPECIALLY IN AREAS THAT
RECEIVED HEAVY RAIN EARLIER. 

DISCUSSION...CONVECTION IS SLOWLY EXPANDING IN COVERAGE AHEAD OF A
COLD FRONT STRETCHED FROM NORTHERN ME INTO EASTERN NY STATE. THE
CONVECTION IS EXPANDING ALONG AN AXIS OF 1000 J/KG 
MLCAPE...COINCIDENT WITH A RIBBON OF 1.50 INCH PRECIPITABLE WATER
AIR. RADARS IN EASTERN NY STATE AND NORTHERN ME HAVE SHOWN HOURLY
RAINFALL RATES NEAR 2.00 INCHES...BUT THIS COULD BE HAIL
CONTAMINATED BASED ON HAIL REPORTS AND DRY AIR IN THE MID LEVELS
(PER RECENT RAP SOUNDINGS). 

THE COLD FRONT IS EXPECTED TO TRUNDLE EASTWARD AHEAD OF A STRONG
SHORT WAVE OVER WESTERN QUEBEC THROUGH THE LATE EVENING HOURS.
AHEAD OF THE FRONT...A 20 KNOT LOW LEVEL SOUTHERLY FLOW WILL
CONTINUE TO SUPPLY 1.25/1.50 INCH PRECIPITABLE AIR TO THE
REGION...AND THE CONVECTION IS EXPECTED TO FEED ON THE 1000 J/KG
MLCAPE AIR THROUGH ABOUT 03Z...WHEN THE 19Z RAP SUGGESTS IT WILL
BECOME EXHAUSTED FROM NORTH TO SOUTH. 

THERE IS A MULTI MODEL SIGNAL FOR 2-4 INCHES OF RAINFALL (BASED ON
THE LATEST HRRR/RAP/12Z NSSL WRK AND 12Z WRF-ARW)... WITH THE
HIGHEST AMOUNTS OVER THE MOUNTAINS OF WESTERN ME. TRAINING REMAINS
A CONCERN THROUGH THE EVENING...AS THE CORFIDI VECTORS BECOME
BETTER ALIGNED WITH THE 850-300 MB FLOW. PORTIONS OF NORTHEAST NY
STATE AND NORTHERN NEW ENGLAND HAVE ALREADY RECEIVED 3 AND 4
INCHES OF RAINFALL (PER RADAR DERIVED DUAL POL STORM TOTALS). THE
ADDITIONAL RAINFALL... ESPECIALLY OVER SATURATED SOIL...IS
EXPECTED TO PRODUCE FLASH FLOODING INTO THE LATE EVENING HOURS.

HAYES

ATTN...WFO...ALY...BTV...CAR...GYX...

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

LAT...LON   47596849 46896742 46126777 45286954 44747064 
            43677241 43187318 42817396 42837423 42857425 
            43537453 44297464 45107421 45877182 46237068 
            46936956 47326905