MESOSCALE PRECIPITATION DISCUSSION 0340
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
745 PM EDT SUN JUN 18 2017

AREAS AFFECTED...CENTRAL AND NORTHERN NY...WESTERN VT

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 182344Z - 190344Z

SUMMARY...THUNDERSTORMS WITH VERY HEAVY RAIN ARE FORECAST TO
CONTINUE ACROSS NORTHERN NEW YORK AND INTO VERMONT INTO THE LATE
EVENING HOURS WITH RAINFALL RATES UP TO 2 INCHES PER HOUR. 
LOCALIZED FLASH FLOODING IS POSSIBLE.

DISCUSSION...A DEEP LAYERED MID-LATITUDE CYCLONE SITUATED JUST
NORTH OF THE GREAT LAKES IS PROVIDING LARGE SCALE ASCENT ACROSS
THIS REGION IN THE PRESENCE OF ANOMALOUS PWS APPROACHING 2 INCHES
AND ROUGHLY 40 KNOTS OF 850MB INFLOW AS INDICATED BY THE LATEST
RAP GUIDANCE.  RADAR IMAGERY SHOWS MULTIPLE LINES OF HEAVY
CONVECTION PROGRESSING FROM SOUTHWEST TO NORTHEAST, WITH COVERAGE
INCREASING OVER THE PAST HOUR.  PERIODS OF TRAINING THUNDERSTORM
ACTIVITY IS POSSIBLE GIVEN DEEP NEARLY UNIDIRECTIONAL FLOW AND
MULTIPLE CONVERGING OUTFLOW BOUNDARIES.

THE LATEST HRRR GUIDANCE, INCLUDING THE LATEST HRRR AND NAM
CONEST, IS SUGGESTING ONE TO LOCALLY THREE INCHES OF RAIN IS
POSSIBLE BY 3Z THIS EVENING.  THIS IS ALSO SUPPORTED BY THE NMMB
AND TO A LESSER EXTENT BY THE ARW.  LOCALIZED AREAS OF FLASH
FLOODING WILL BE POSSIBLE.

HAMRICK

ATTN...WFO...ALY...BGM...BTV...BUF...

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

LAT...LON   45207393 45147305 44857254 44407251 43897284
            43427321 42917385 42517446 42067529 42057628
            42187679 42717697 43447690 43977654 44497609
            44957538 45187468