Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2
000
FXAK02 KWNH 251706
PMDAK

ALASKA EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
106 PM EDT SAT APR 25 2015

VALID 12Z WED APR 29 2015 - 12Z SUN MAY 03 2015

FOR THE HIGH LATITUDES... THE MODELS/ENSEMBLES HAVE YET TO SORT
OUT HOW TO HANDLE ENERGY EJECTING EAST OF NORTHERN JAPAN EARLY
NEXT WEEK AS IT STREAMS ACROSS THE NORTH PACIFIC. THE 00Z
GFS/GEFS/UKMET DEPART MARKEDLY FROM THE CANADIAN/ECMWF/ECENS MEAN
AS WELL AS CONTINUITY IN SHOWING MUCH LESS DEVELOPMENT OF A
TRAILING SYSTEM COMPARED TO A LEAD SYSTEM THAT SLIPS SOUTHEASTWARD
FROM THE BERING ACROSS THE ALEUTIANS TO START THE PERIOD ON WED.
12Z GFS STAYED WITH ITS EARLIER RUNS. OPTED TO USE THE STRONGER
CLUSTER/CONTINUITY THOUGH DETAIL DIFFERENCES STILL PLAGUE THE
FORECAST. RESULT WAS TO EMPHASIZE A MORE SUPPRESSED STORM TRACK IN
THE SOUTHERN BERING AND ACROSS THE ALEUTIANS THAN THE FARTHER
NORTH GFS. HOWEVER... CONFIDENCE IS LACKING GIVEN THE DIFFERENCES
SEEN AT SHORT LEAD TIMES. THINGS SHOULD GET SORTED OUT IN ANOTHER
MODEL CYCLE OR TWO. PRECIP FOCUS WILL BE ALONG AND SOUTH OF ABOUT
61N FROM THE ALEUTIANS TO SOUTHERN CENTRAL ALASKA TO THE
PANHANDLE.


FRACASSO

$$





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