Small Craft Advisory 1071, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM AST MON NOV 20 2006

.DISCUSSION...NCEP MODEL INITIALIZATIONS REASONABLE. GFS IN SHORT
TERM HANDLES LOW SYSTEM APPROACHING THE ALEUTIANS BETTER. GFS ALSO
DOES FAIR JOB MAINTAINING INVERTED TROUGH IN THE GULF AS COLD
ADVECTION CONTINUES.

.UPPER AIR...RESIDENT LOW CENTER OVER THE NE PACIFIC HAS CHANGED
LITTLE OVER THE LAST WEEK OR SO. FORECAST IS TO MOVE CENTER SE AND
WEAKEN IT. HOWEVER...COLD ADVECTION WILL LIKELY MAINTAIN PORTION OF
LONGWAVE OVER THE EASTERN MAINLAND/EASTERN GULF THROUGH THU. HIGH
AMPLITUDE RIDGE OVER THE BERING SEA MOVES TO THE EASTERN BERING SEA
WED AND SHOULD CHANGE VERY LITTLE THROUGH THU NIGHT. THIS WILL TEND
TO MAINTAIN NW FLOW ACROSS THE WESTERN MAINLAND TO WESTERN GULF. GFS
STRENGTHENS THE NORTH PACIFIC JET AND UNDERCUTS EASTERN BERING SEA/AK
PEN RIDGE FRI AFTN/SAT. BY SUN A FAIRLY STRONG LOW CENTER ENTERS THE
BERING SEA AND SETS UP SW FLOW FROM THE ALEUTIANS TO THE SW MAINLAND.
GFS ENSEMBLES SHOWS HUGE SPREAD IN MEMBERS AND NEWEST RUNS CONTINUE
TO PUSH TIMING BACK. SO FOR NOW WILL HOLD STATUS QUO.

.SURFACE EAST...
NOT MUCH CHANGE REALLY EXPECTED FOR NEXT COUPLE OF DAYS. COLD HIGH
MAINTAINS OVER THE MAINLAND AND LOW PRESSURE TROUGH CONTINUES OVER
THE GULF(ALTHOUGH SOMEWHAT WEAKER).  PRESSURE GRADIENTS LIKELY TO
DIMINISH SOME TODAY...HOWEVER BRISK GAP WINDS WILL CONTINUE OVER THE
NORTH GULF AND PORTIONS OF SOUTHCENTRAL.

.SURFACE WEST...WINDS OVER THE AK PEN/BRISTOL WILL DIMINISH TONIGHT
AS THE TROUGH OVER THE GULF OF ALASKA WEAKENS AND BERING SEA RIDGE
SHIFTS EAST. EXPECT STRATUS AND SOME FOG LIKELY TO BE ISSUES FOR
COASTAL SW AK TONIGHT AND TUE. LOW COMPLEX SW OF THE ALEUTIANS LIKELY
TO KEEP BRISK SE WINDS OVER THE ALEUTIANS THROUGH TUE NIGHT.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...ICE JAM FLOOD WARNING ZONE 121.
MARINE...GALE 121 129 172 175 176
         HEAVY FREEZING SPRAY 121 129
FIRE WEATHER...NONE.
RMC NOV 06