Small Craft Advisory 405, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM ADT THU MAY 12 2005

.DISCUSSION...

...HEMISPHERIC...
5 WAVE PATTERN WITH LARGE FLATTENED TROUGH OVER ALASKA. MAIN FEATURE
IS ELONGATED ZONAL FLOW FROM JAPAN EAST INTO THE LOWER 48 COAST.

...AT THE SURFACE...
GENERALLY WEAK SURFACE FEATURES WITH FOUR LOWS ALL SOUTH OF THE STATE
STRETCHING FROM 165E TO 145W. RADAR RETURNS ARE THE MOST IMPRESSIVE
NEAR AND TO THE WEST OF MIDDLETON ISLAND AS MOISTURE AROUND A LOW
MOVES TOWARD THE STATE.

...FOR THE FORECAST...
GOOD AGREEMENT AT 500 MB AS THE FLAT FLOW FROM ASIA CONTINUES TO
STREAM EASTWARD TO THE WEST COAST. OUT TO 60 HOURS ALL AGREE WITH
MAIN UPPER LOW BEING JUST TO THE SOUTHEAST OF KODIAK.

SURFACE PROGS DO NOT SHOW THE SAME LEVEL OF CERTAINTY FOR LOCATIONS
SOUTH OF ALASKA. AS IS TYPICALLY THE CASE WITH LARGE COMPLEX AREAS OF
LOW PRESSURE, THE MODELS TEND TO DO A POOR JOB WITH EXACT POSITIONS
AND ACCURATELY PREDICTING THE PRESSURE LEVELS. SO, CONFIDENCE WITH
THE PACKAGE IS BELOW AVERAGE. OVERALL PREFER THE UKMET AS IT COMES
THE CLOSEST TO A MEDIAN SOLUTION.

FURTHER OUT WEST...ALL FOUR ARE IN AGREEMENT WITH A NORTHERLY FLOW
FROM THE NORTHERN BERING SEA TO THE WESTERN ALEUTIANS.

FURTHER OUT...LOW COMPLEX SHIFTS TO THE EAST AND NORTH BY SUNDAY.
MOISTURE WILL SPREAD INLAND OVER A LARGE CHUNK OF THE EASTERN AOR BY
THIS TIME. OUT WEST, COOL NORTHERLY FLOW SETS UP.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALES 2A 3A 3C
FIRE WEATHER...NONE

BELL MAY 05