MESOSCALE PRECIPITATION DISCUSSION 0749
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1121 PM EDT THU OCT 20 2016
 
AREAS AFFECTED...NEW YORK...PENNSYLVANIA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 210320Z - 210720Z
 
SUMMARY...FLASH FLOODING REMAINS POSSIBLE ACROSS PARTS OF SOUTH
CENTRAL NY AND NORTH CENTRAL PA THROUGH 07Z BEFORE WANING.

DISCUSSION...DEEP AND VIGOROUS CONVECTION CONTINUES TO DEVELOP AND
PERSIST JUST NORTH OF THE MERGER OF A COLD FRONT AND WARM FRONT
ACROSS NORTH CENTRAL PA. CELL MOTIONS HAVE GENERALLY SHOWN FORWARD
PROPAGATING CHARACTERISTICS WITH HOURLY RAIN RATES OF 1 TO 1.5
INCHES. 

WITH THE UPPER TROUGH APPROACHING OVERNIGHT...WIND PROFILES SHOULD
BECOME MORE UNIDIRECTIONAL...THUS SUPPORTING THE POTENTIAL FOR
SLOWER CELL MOTIONS AND POSSIBLY BACKBUILDING.  

GIVEN THE INTENSITY OF THE UPPER TROUGH...INDICATIONS OF MULTIPLE
WAVES ON THE TRAILING STATIONARY FRONT AND AT LEAST A FEW MORE
HOURS OF SUFFICIENT CONVECTIVE INSTABILITY TO SUPPORT DEEPER
UPDRAFTS...
HOURLY RAIN RATES ARE LIKELY TO REMAIN 1 TO 2 INCHES BEFORE
WANING...WITH SOME CELLS AFFECTING AREAS THAT HAVE ALREADY
RECEIVED HIGH TOTALS. THE RISK FOR FLASH FLOODING SHOULD DIMINISH
AFTER 07Z AS INSTABILITY DIMINISHES.

JAMES

ATTN...WFO...BGM...BUF...CTP...

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

LAT...LON   43407585 42757535 41657597 40767721 40907804 
            41797813 42977729