Prognostic Meteorological Discussion
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FXAK02 KWNH 071749
PMDAK

ALASKA EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1249 PM EST SUN FEB 07 2016

VALID 12Z THU FEB 11 2016 - 12Z MON FEB 15 2016

...GUIDANCE AND UNCERTAINTY ASSESSMENT...

THE WPC ALASKAN MEDIUM RANGE PRODUCT SUITE HAS BEEN PRIMARILY
DERIVED FROM THE REASONABLY WELL CLUSTERED 12 UTC GFS...06 UTC
GEFS MEAN...AND 00 UTC ECMWF/ECMWF ENSEMBLE MEAN DAYS
4-8...GRADUALLY TRANSITIONING EMPHASIS FROM THE DETERMINISTIC
MODELS 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 GFS/ECMWF/CANADIAN STILL OFFER SOME VARIANCE WITH TIMING...BUT
OVERALL AGREE TO SHOW MID-UPPER LEVEL TROUGH ENERGIES AND COOLING
CUTTING FROM THE SRN ARCTIC ACROSS NRN/NWRN AK WED/THU THAT SHIFTS
TO THE VICINITY OF THE BERING STRAIT FRI INTO NEXT WEEKEND.
UNDERNEATH...THIS PATTERN REMAINS HIGHLIGHTED BY AN AMPLIFIED MEAN
RIDGE EXTENDING NWWD FROM WRN CANADA SERN AK TO THE INTERIOR. THIS
HAS BEEN TENDING TO SHIELD AN ACTIVE FLOW OF DEEPENING LOWS FROM
THE NERN PACIFIC UP TOWARD THE ALEUTIANS/SW AK...AND ALSO WORKING
INCREASINGLY OUT WITH TIME ACROSS THE GULF OF AK AS EMBEDDED DEEP
LOWS WRAP AROUND THE A MEAN LOW/TROUGH POSITION CENTERED JUST
SOUTH OF THE ALEUTIANS/SW AK. WRAPPING PCPN SHOULD FOCUS ACROSS
THESE AREAS AND ALSO INTO COASTAL AREAS/TERRAIN OF SRN/SERN AK
WITH PERIODICALLY ENHANCED LEAD LOW LEVEL INFLOW.

SCHICHTEL

$$




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