ALASKA EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
107 PM EDT MON JUN 10 2013

VALID 12Z FRI JUN 14 2013 - 12Z TUE JUN 18 2013


THE GLOBAL NUMERICAL MODELS ARE INDICATING A RETROGRESSION OF THE
LONGWAVES ACROSS CENTRAL NORTH AMERICA AND THE ADJACENT PACIFIC
OCEAN AT THE MEDIUM RANGE, WITH THE TROUGH OVER THE UNITED STATES
PACIFIC NORTHWEST DAY 3 RELOADING OFFSHORE BY DAY 7. THE GFS HAS
NOT BEEN CONSISTENT WITH THE DETAILS OF THIS SHUFFLING, NOR HAS IT
BEEN IN SYNC WITH ITS ATTENDANT ENSEMBLE MEANS RUN TO RUN. THE
ECMWF HAS BEEN BETTER, BUT ELECTED TO USE THE ECENS MEAN AS A BASE
THIS FORECAST PACKAGE, ADJUSTING ITS MASS FIELDS MANUALLY SINCE
PATTERN CHANGES ARE HANDLED WITH THE LEAST ERROR BY THE MEAN
CHARTS. MOST OF THE PRECIPITATION THIS PERIOD SHOULD BE DIRECTED
AT THE UPPER ALEUTIANS AND NEARBY MAINLAND WHERE THE BEST JET
DYNAMICS ARE ANTICIPATED.


CISCO