Quantitative Precipitation Forecast
Issued by NWS

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FOUS30 KWBC 220837
QPFERD

EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
434 AM EDT WED OCT 22 2014

...VALID 06Z WED OCT 22 2014 - 12Z THU OCT 23 2014...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
25 SE BHB 80 SE RKD 95 SSE RKD 95 ENE PVC 20 E PVC 15 NE PYM
15 ESE MQE BOS BED 10 S AFN 10 WSW AFN EEN 15 SSE VSF 10 E VSF
10 E LEB 20 NE 1P1 15 ENE MWN 30 ENE BML 20 N WVL 15 SSE BGR
25 SE BHB.

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
20 W HQM 35 NW HQM 25 SSE UIL 25 ESE UIL 20 S CLM 30 SSE CLM
20 NNW SHN 10 NW SHN 15 WSW SHN 20 E HQM 20 ESE HQM 25 W TDO
25 WNW KLS 20 E AST 20 ESE AST 30 W SPB 20 ENE S47 20 WNW MMV
30 W SLE 20 ENE ONP 20 ESE ONP 20 WNW EUG 15 WNW EUG 10 WNW EUG
20 ESE CVO 20 SE SLE 15 E SLE 30 ESE UAO 45 S CZK 45 NW RDM
35 WNW RDM 35 WSW RDM 50 SW RDM 60 SW RDM 55 ENE RBG 35 E RBG
20 E RBG 15 ENE RBG 10 WSW RBG 25 NW SXT 30 SW SXT 25 ENE CEC
20 SE CEC 20 SSW CEC 25 WSW CEC 35 WNW CEC 50 NW CEC 45 NW OTH
20 W HQM.

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
15 S ACY 10 WNW ACY VAY TTN SMQ 10 SSE 12N 12N 15 ESE FWN
20 NNE CDW 15 W HPN 15 NNE TEB 10 NE TEB LGA 10 ESE JFK
30 SE JFK 35 E MJX 35 SSE MJX 30 ESE ACY 15 S ACY.


0830 UTC UPDATE

NJ/WESTERN LONG ISLAND

A SLIGHT RISK AREA WAS ADDED EARLY THIS MORNING IN RESPONSE TO
SLOW MOVING CONVECTION THAT HAS FLARED ALONG THE NJ/WESTERN LONG
ISLAND COASTS.  SURFACE ANALYSIS EARLY THIS MORNING IS SHOWING A
SURFACE LOW OFF THE SOUTHERN NJ COAST WITH AN AXIS OF
FRONTOGENESIS TO THE NORTHWEST OF THIS LOW ALONG THE NJ COAST INTO
WESTERN LONG ISLAND.  THE LATEST RAP32 IS SHOWING AN AREA OF
STRONG BOUNDARY LAYER CONVERGENCE REMAINING ALONG THE NJ COAST
THROUGH THE REMAINDER OF THE EARLY MORNING HOURS AND THEN
WEAKENING AFTER 1200 UTC AS THE SURFACE LOW PULLS FARTHER TO THE
EAST.  DUAL POL RADAR ESTIMATES OVER COASTAL SOUTH CENTRAL NJ SHOW
1 HOURS TOTALS IN EXCESS OF 3" WHERE CONVECTION HAS REMAINED
STATIONARY OR TRAINED.  SIMILAR SHORT TERM AMOUNTS ARE POSSIBLE
OVER THE NEXT SEVERAL HOURS ALONG THE NJ COAST INTO WESTERN LONG
ISLAND WHERE SLOW MOVING CELLS OCCUR.  THIS IS SUPPORTED BY THE
0600 AND 0700 UTC HRRR RUNS THAT SHOW 6 HOUR PRECIP TOTAL MAXIMA
OF 3-5" ALONG THE NJ COAST.  CAN NOT RULE OUT HEAVY RAINS MOVING
FARTHER INLAND INTO FAR NORTHEAST NJ WHERE FFG VALUES ARE
LOWEST---BUT AT THE MOMENT---BELIEVE HEAVIEST AMOUNTS WILL REMAIN
CLOSER TO THE COAST AND AXIS OF STRONG FRONTOGENESIS AND BOUNDARY
LAYER CONVERGENCE.  SEE  WPC MESOSCALE PRECIPITATION DISCUSSION
#0428 VALID THROUGH 1230 UTC WEDNESDAY OCT 22 FOR FURTHER DETAILS.


WA/OREGON COAST RANGE INTO THE OREGON CASCADES

CONCERNS FOR RUNOFF ISSUES WILL BE ACROSS THE WA/OREGON COAST
RANGE INTO THE OREGON CASCADES WHERE WIDESPREAD HEAVY
PRECIPITATION TOTALS ARE LIKELY THIS PERIOD.  LATEST BLENDED TPW
IMAGERY SHOWS A WELL DEFINED PLUME OF HIGH PW VALUES STRETCHING
ACROSS THE NORTHEAST PACIFIC AND TOWARD THE PACIFIC NORTHWEST
ALONG AND AHEAD OF THE SURFACE COLD FRONT EXPECTED TO SINK SLOWLY
SOUTHEASTWARD INTO THE PACIFIC NORTHWEST THIS PERIOD  STRONG
ONSHORE SOUTH SOUTHWESTERLY FLOW IN THIS HIGH PW AXIS ALONG AND
AHEAD OF THE FRONT WILL SUPPORT WIDESPREAD HEAVY PRECIPITATION
TOTALS ACROSS THE PACIFIC NORTHWEST TO THE WEST OF THE WA/OREGON
CASCADES TO THE WA/OREGON COAST RANGE AND INTO THE NORTHWEST
CALIFORNIA COAST RANGE.  OVERALL---THERE IS GOOD MODEL AGREEMENT
WITH THIS PRECIPITATION SCENARIO---LEADING TO A RATHER HIGH
CONFIDENCE FORECAST ACROSS THESE REGIONS.  RUNOFF ISSUES ARE
POSSIBLE ALONG THE WA AND OREGON COAST RANGES AND INLAND INTO THE
OREGON CASCADES GIVEN THE PERSISTENT STRONG ONSHORE FLOW.
WIDESPREAD 2-4" PRECIPITATION TOTALS POSSIBLE ACROSS THESE
AREAS---WITH ISOLATED TOTALS IN EXCESS OF 5"+ POSSIBLE.

NORTHEAST MA---SOUTHERN NH INTO SOUTHWEST MAINE


THE THE CLOSED LOW INITIALLY OVER THE MID ATLANTIC WILL BE
SWINGING SLOWLY NORTHEASTWARD OFF THE NORTHERN MID ATLANTIC COAST
THIS PERIOD.  PERSISTENT ONSHORE EASTERLY FLOW TO THE NORTH AND
EAST OF THIS MID TO UPPER LEVEL CLOSED LOW WILL KEEP WET
CONDITIONS FROM THE COASTAL MID ATLANTIC---INTO EASTERN NY AND
NEARLY ALL OF NEW ENGLAND.  THE STRONGEST---MOST PERSISTENT
ONSHORE FLOW IS TARGETING PORTIONS OF EASTERN NEW ENGLAND FROM
EASTERN MA INTO SOUTHERN NH AND SOUTHERN MAINE--WHERE THE MODEL
CONSENSUS IS FOR THE HEAVIEST QPF AMOUNTS THIS PERIOD.  RUNOFF
ISSUES MAY DEVELOP ACROSS THESE AREAS--ESPECIALLY OVER SOUTHWEST
MAINE WHERE THE UPCOMING PERIOD WILL BE THE SECOND DAY OF HEAVY
PRECIPITATION TOTALS.

ORAVEC
$$





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