Prognostic Meteorological Discussion
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2
000
FXAK02 KWNH 191946
PMDAK

ALASKA EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
345 PM EDT FRI SEP 19 2014

VALID 12Z TUE SEP 23 2014 - 12Z SAT SEP 27 2014

DESPITE CONVERGENCE TOWARD A COMMON SOLUTION ACROSS THE
SUBTROPICAL PACIFIC INTO THE CONUS OVER THE NEXT WEEK... THE
ENSEMBLE MEANS IN THE HIGH LATITUDES STILL EXHIBIT MODEST SPREAD
AND LACKLUSTER CONTINUITY. THE DETERMINISTIC MODELS ARE WORSE...
BEING SENSITIVE TO SMALLER DIFFERENCES IN THE SHORT RANGE THAT
GROW QUITE NOTICEABLY WITH TIME.

LARGE SCALE PATTERN SHOULD SEE CONTINUED TROUGHING IN THE GULF
WITH RIDGING DEVELOPING IN THE BERING SEA. ENERGY IN THE ARCTIC
OCEAN SHOULD PASS THROUGH THE INTERIOR/NORTH SLOPE THOUGH THE
ECMWF HAS BACKED OFF QUITE MARKEDLY OVER ITS PAST RUNS. THE GFS
HAS BEEN MORE CONSISTENT /THOUGH NOT GREAT/ BUT AT LEAST MATCHES
MORE WITH THE GEFS/ECENS MEANS. THEREAFTER... THE EC ENSEMBLES ARE
QUICKER TO THE IN SITU UPPER LOW OUT OF THE BERING SEA MIDWEEK
WHILE THE GFS SEEMS TO LAG BEHIND. A COMPROMISE SOLUTION WAS
USED... AMONG THE ENSEMBLES. HAVE LITTLE CONFIDENCE IN THE
FORECAST FOR THE END OF NEXT WEEK... BUT THERE SEEMS TO BE AT
LEAST A GOOD CONSENSUS - AT THIS TIME -- FOR A DEEPER STORM JUST
EAST OF KAMCHATKA NEXT WEEKEND... RELATED TO THE EXTRATROPICAL
TRANSITION OF TROPICAL STORM FUNG-WONG. HOWEVER... THE VERY
CHANGEABLE FORECAST TRACK /WESTWARD AND WEAKER/ SEEN OVER THE PAST
FEW DAYS DOES NOT LEND ITSELF TO EVEN AVERAGE CONFIDENCE.


FRACASSO

$$




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