Prognostic Meteorological Discussion
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FXAK02 KWNH 261838
PMDAK

ALASKA EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
237 PM EDT FRI MAY 26 2017

VALID 12Z TUE MAY 30 2017 - 12Z SAT JUN 03 2017

BIG PICTURE REMAINS IN GOOD AGREEMENT OVERALL, FEATURING TROUGHING
FROM THE BERING SEA ACROSS THE ALEUTIANS AND SW OF THE GULF OF
ALASKA (S OF KODIAK). THIS SHOULD KEEP THE MAIN LOW PRESSURE
CONFINED TO JUST SOUTH OF KODIAK AS IT SENDS ITS ATTENDANT FRONT
INTO THE PANHANDLE WEDNESDAY. TRAILING UPPER TROUGH MAY SUPPORT A
WEAK SFC FRONT THAT WOULD ROTATE AROUND THE UPPER LOW LATER NEXT
WEEK. A CONSENSUS BLEND OF THE 12Z GFS AND 00Z ECMWF/ECENS MEAN
AND 00Z GFS/GEFS MEAN OFFERED A GOOD STARTING POINT THAT KEPT
ALONG THE LINES OF CONTINUITY. THE EXCEPTION TO THIS WAS OVER THE
NORTH SLOPE WHERE THE GUIDANCE NOW STRONGLY FAVORED A MORE ROBUST
TROUGH OR NEARLY CLOSED LOW THAT LIFTS ACROSS THE ARCTIC CIRCLE
INTO THE BEAUFORT SEA WHEREAS THE MODELS FROM 24 HRS AGO HAD IT
WEAKENING MUCH SOONER. THIS SUPPORTS A GREATER CHANCE OF MORE
WIDESPREAD AND HIGHER POPS NORTH OF THE ALASKA RANGE TO THE NORTH
SLOPE. NEVERTHELESS, UPPER RIDGING SHOULD STILL FOLD OVER INTO THE
INTERIOR FROM NW CANADA BETWEEN BROAD LOWER HEIGHTS IN THE ARCTIC
AND THE UPPER LOW SW OF THE GULF. TRENDED TOWARD THE 00Z ECMWF AND
ECENS/GEFS MEANS BY NEXT THURSDAY AS THE GFS SEEMED A BIT TOO
STRONG WITH ANOTHER SHORTWAVE AND SFC FRONT MOVING EASTWARD ALONG
50N COMPARED TO THE ENSEMBLES, THOUGH ITS FORECAST FOR THE REST OF
THE AREA WAS OK.


FRACASSO


$$





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