Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2
000
FXAK02 KWNH 211855
PMDAK

ALASKA EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
254 PM EDT THU AUG 21 2014

VALID 12Z MON AUG 25 2014 - 12Z FRI AUG 29 2014

ACTIVE PATTERN FOR ALASKA IN THE MEDIUM RANGE... WITH POOR
CONTINUITY WITHIN THE ENSEMBLES AND ESPECIALLY THE DETERMINISTIC
MODELS. ONE OF THE CHANGES TO THE FORECAST LIES WITH THE HANDLING
OF ENERGY NEAR THE GULF OF OKHOTSK/KAMCHATKA THIS WEEKEND. EARLIER
GUIDANCE WAS WEAKER WITH THIS FEATURE BUT WITH AN ALMOST
UNILATERAL TREND TOWARD A MUCH STRONGER SHORTWAVE/CLOSED LOW... IT
IS HARD TO IGNORE. HOWEVER... THE EC ENSEMBLES ARE OVERALL
STRONGEST WITH THIS WESTERN UPPER LOW WHILE THE 06Z GEFS MEMBERS
ARE IN BETWEEN THE STRONGER EC MEMBERS AND WPC CONTINUITY. THE
RECENT GFS/ECMWF RUNS DEPART FROM THE BROAD GEFS/ECENS CLUSTERING
BY TUE/D5 TOWARD THE EASTERN ALEUTIANS RATHER THAN TOWARD THE
BERING STRAIT. CONSIDERING ALL THE CHANGES OVER THE PAST 24 HRS...
FELT A MIDDLE GROUND SOLUTION WAS BEST... WHICH FAVORS THE 06Z
GEFS MEAN. TO THE NORTH... TOWARD THE END OF THE PERIOD... THERE
IS BETTER AGREEMENT /AT LEAST TODAY/ FOR A FAIRLY STRONG UPPER LOW
TO PUSH TOWARD THE DATELINE IN THE ARCTIC... PUSHING A COLD FRONT
INTO FAR NW ALASKA AND PERHAPS OVERTAKING THE SYSTEM TO ITS SOUTH.

RAINY/WINDY CONDITIONS SHOULD PREVAIL OVER SW AREAS WHILE THE
PANHANDLE SHOULD SEE IMPROVING CONDITIONS AFTER THE LEAD SYSTEM
PASSES EAST INTO CANADA. TEMPERATURES SHOULD BE WITHIN SEVERAL
DEGREES OF AVERAGE STATE-WIDE.


FRACASSO

$$





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.