Gale Warning 1057, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
530 AM AST MON DEC 12 2005

.DISCUSSION...
UKMET INITIALIZES BEST THIS MORNING BUT SOLUTION QUICKLY DIVERGES
FROM ETA AND GFS BY 24 HOURS. ETA AND GFS IN GOOD AGREEMENT THROUGH
48 HOURS BEFORE ETA COMPLICATES THE FORECAST BY NOT DEVELOPING
SURFACE LOW AS DEEP AS THE GFS. CONFIDENCE IN ETA PAST 48 HOURS IS
LOW GIVEN THAT THE WAVES ENTERING ARE FORECAST AREA ARE DEVELOPING
OUTSIDE THE ETA DOMAIN. GFS SOLUTION IS THE BEST AND FORECAST WAS
ADJUSTED ACCORDINGLY TO REFLECT THAT. EXTENDED FORECAST WAS ONLY
TWEAKED GIVEN THE UNCERTAINTY AND POOR RUN TO RUN CONSISTENCY PAST 60
HOURS.

500MB...
MAIN UPPER FEATURE IS 501 DAM LOW IN THE BERING SEA RETROGRADING
ALONG 55N FROM 175W ACROSS THE INTERNATIONAL DATELINE. UNRELENTING
SUPPLY OF SHORTWAVES PIVOTING AROUND BASE OF UPPER TROUGH COINCIDING
WITH 185 KT JET FLOWING W-E ALONG THE 40TH PARALLEL. UPPER RIDGE
STILL BUILDING WITH AXIS ALONG THE BC COAST AND AK PANHANDLE. THIS
RIDGE WILL EVENTUALLY SHIFT EAST BY FRIDAY AS NORTH PACIFIC JET
BECOMES MORE AMPLIFIED DEEPENING THE TROUGH IN THE VICINITY OF 160W.

SURFACE...
THE SURFACE REFLECTIONS OF THE UPPER SHORTWAVES ARE STRONG LOW
PRESSURE SYSTEMS DEVELOPING OFF THE KAMCHATKA PENINSULA AND REACHING
MATURITY NEAR 170W. IT IS HERE WHERE THEY LOSE UPPER SUPPORT AND
WEAKEN AS THEY TURN NORTH TOWARD THE AKPEN. THIS TREND WILL CONTINUE
FOR THE REMAINDER OF THE WEEK BEFORE THE UPPER TROUGH BEGINS TO
DEEPEN. THE DEEPENING TROUGH WILL TRANSLATE TO SURFACE LOWS
PROGRESSING FURTHER EAST BEFORE TURNING NORTH INTO SOUTHCENTRAL AK.
IN THE MEAN TIME...A TIGHT PRESSURE GRADIENT IN THE NORTHERN GULF IS
RESULTING IN STRONG WINDS OVER MUCH OF THE MARINE ZONES AND IS NOW
SPILLING OVER INTO OUR COASTAL ZONES. KODIAK ALREADY EXPERIENCING
GALE FORCE WINDS THIS MORNING. GALE AND STORM FORCE WINDS EXPECTED IN
THE MAJORITY OF THE MARINE ZONES IN THE EAST. STRONG WINDS WILL ALSO
BE A NUISANCE INLAND THROUGH CHANNELED TERRAIN.

OUT WEST...LOW LEVEL WIND SHEAR OVER THE INTERIOR AND SCATTERED RAIN
AND SNOW SHOWERS AND BREEZY CONDITIONS OVER MARINE ZONES. A COUPLE OF
INTERESTING NOTES FROM THE 12Z SOUNDINGS...PAKN REPORTED WINDS 60 KT
JUST OFF THE SURFACE AND PABE HAD 40 KT WINDS AT 2000 FT. 50 KT WINDS
REPORTED AT THE SURFACE ALONG THE COASTAL SECTIONS OF THE DELTA
RESULTING IN ISOLATED BLIZZARD CONDITIONS. THIS ACTIVE WEATHER
PATTERN WILL HAVE TO BE MONITORED CLOSELY INTO THE WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...SEE MARINE PACKAGES.
FIRE WEATHER...NONE.

AB DEC 05