Preliminary Forecasts
Issued by NWS

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FXUS02 KWNH 050505
PREEPD

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1204 AM EST FRI FEB 05 2016

VALID 12Z MON FEB 08 2016 - 12Z FRI FEB 12 2016

...ANOTHER SNOW THREAT FOR THE NORTHEAST EARLY NEXT WEEK...

...GUIDANCE EVALUATION/PREFERENCES...

AMPLIFIED PATTERN WILL SLOWLY EASE THROUGH NEXT WEEK BUT REMAIN IN
A RIDGE/TROUGH ORIENTATION ACROSS THE WEST/EAST. RECENT GUIDANCE
SHOWS DECENT CLUSTERING THROUGH THE FORECAST PERIOD AND A
MULTI-MODEL/ENSEMBLE BLEND OF THE 18Z GFS/GEFS AND 12Z ECMWF/ECENS
MEAN WAS USED AS A STARTING POINT. ACTIVITY WILL BE CENTERED
MOSTLY IN THE GREAT LAKES/MID-ATLANTIC/NORTHEAST AS A COLD UPPER
LOW SWINGS THROUGH THE REGION, INDUCING A MILLER-B TYPE
CYCLOGENESIS -- WITH NEW SFC LOW DEVELOPMENT NEAR OR JUST EAST OF
THE DELMARVA BY TUESDAY MORNING BEFORE DEEPENING AND MOVING
NORTHEASTWARD. HIGH PRESSURE AND THEN PERHAPS A NORTHERN STREAM
CLIPPER WILL FOLLOW IN ITS WAKE. THE WEST WILL REMAIN RATHER QUIET
UNTIL LATER NEXT WEEK AS THE RIDGE SHIFTS SLIGHTLY EASTWARD
ALLOWING A FRONT TO REACH THE WA/OR COAST.


...SENSIBLE WEATHER HIGHLIGHTS...

WEST:  STRONG RIDGING ALOFT WILL PROMOTE WARM AND DRY CONDS AT
MOST LOCATIONS --  PLUS 5-15F OR SLIGHTLY GREATER ANOMALIES.
INTERIOR VALLEYS IN NV/UT/CO MAY NOT BREAK THROUGH LOCAL
INVERSIONS TO PARTAKE IN SAID "WARMTH" (RELATIVE). RECORD HIGHS
AND RECORD HIGH MINIMA BOTH APPEAR POSSIBLE ON MONDAY AND TUESDAY
ACROSS CALIFORNIA.

NORTH/PLAINS/GREAT LAKES: E-W TEMPERATURE GRADIENT DUE TO THE
UPPER FLOW... WITH DOWNSLOPING AND RELATIVE WARMTH IN MONTANA
TRENDING TO BELOW AVERAGE TEMPERATURES UNDER THE TROUGHING.
NORTHERLY COMPONENT OF THE WIND WILL MAINTAIN SEVERAL DAYS OF LAKE
EFFECT SNOW, ESPECIALLY FOR THE U.P. OF MICHIGAN AND WESTERN LOWER
MICHIGAN.

SOUTHEAST: TEMPERATURES WELL BELOW AVERAGE (ABOUT 5-15F BELOW
AVERAGE) TRENDING BACK TOWARD CLIMATOLOGY BY THE END OF THE WEEK,
BUT WITH LITTLE PRECIP OUTSIDE THE SOUTHERN APPALACHIANS.

EAST: THE POTENTIAL REMAINS FOR MEANINGFUL SNOWFALL OVER PARTS OF
THE MID ATLANTIC/NORTHEAST WITH THE MON NIGHT-WED SYSTEM. THESE
TYPE OF SYSTEMS INHERENTLY HAVE LOWER PREDICTABILITY ON THEIR SW
SIDES -- I.E., DC METRO AREA -- AND RECENT VERIFICATION OF EAST
COAST SYSTEMS HAS SHOWN THAT PRECIP EDGES HAVE NOT BEEN
WELL-PREDICTED (ESPECIALLY N/NW SIDE). ENSEMBLE GUIDANCE IS OF
GREAT VALUE IN THE MEDIUM RANGE AND AMPLIFIED PATTERNS OFTEN BRING
SURPRISES. NONETHELESS, ANOTHER SNOW THREAT WILL REMAIN IN PLAY
FROM VA/MD TO MAINE NEXT TUE/WED.


FRACASSO/ROTH/RAUSCH

$$




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