Prognostic Meteorological Discussion
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FXAK02 KWNH 081900
PMDAK

ALASKA EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
159 PM EST MON FEB 08 2016

VALID 12Z FRI FEB 12 2016 - 12Z TUE FEB 16 2016

...GUIDANCE AND UNCERTAINTY ASSESSMENT...

THE WPC ALASKAN MEDIUM RANGE PRODUCT SUITE WAS PRIMARILY DERIVED
FROM THE REASONABLY WELL CLUSTERED GUIDANCE FROM THE 06 UTC GEFS
MEAN AND 00 UTC ECMWF/ECMWF ENSEMBLE MEAN DAYS 4-8...GRADUALLY
TRANSITIONING EMPHASIS ON THE DETERMINISTIC ECMWF TO THE ENSEMBLE
MEANS WITH TIME CONSISTENT WITH SLOWLY DECREASING FLOW
PREDICTABILITY. OVERALL...MODELS AND ENSEMBLES STILL OFFER BELOW
NORMAL FORECAST SPREAD AND BETTER THAN NORMAL CONTINUITY DAYS 4-8
WITH THE WEATHER PATTERN EVOLUTION.

...PATTERN AND WEATHER HIGHLIGHTS/THREATS...

THE WPC GUIDANCE BLEND SHOWS A MID-UPPER LEVEL TROUGH SHIFT FROM
NW AK TO THE BERING STRAIT FRI INTO NEXT WEEKEND.
UNDERNEATH...THIS PATTERN REMAINS HIGHLIGHTED BY AN AMPLIFIED MEAN
RIDGE EXTENDING NWWD FROM WRN CANADA TO THE ALASKAN INTERIOR. THIS
HAS BEEN TENDING TO SHIELD AN ACTIVE FLOW OF ORGANIZED SURFACE
LOWS AND FRONTAL SYSTEMS. THESE LOWS/WRAPPING PCPN SHOULD WORK
TOWARD THE ALEUTIANS/SW AK AND INCREASINGLY ACROSS THE GULF OF AK
OVER THE NEXT WEEK AROUND A TRANSIENT MEAN MID-UPPER LEVEL TROUGH
POSITION CENTERED JUST SOUTH OF THE ALEUTIANS/SW AK. FAVORABLE
LEAD MOISTURE INFLOW SHOULD FOCUS HEAVIER PCPN INTO COASTAL
AREAS/TERRAIN OF SRN/SERN AK IN THIS PATTERN. UPSTREAM TROUGH
DEVELOPMENT OFF NERN ASIA SEEM SLATED TO ALLOW FOR SOME TRANSITION
TO MORE BERING SEA SYSTEMS EARLY NEXT WEEK.

SCHICHTEL

$$





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