Small Craft Advisory 35, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
605 AM AST SUN JAN 13 2008

.MODEL DISCUSSION...
MODELS IN FAIR AGREEMENT...STILL PREFER THE GFS SOLUTION. THE 00Z NAM
A LITTLE BEHIND ON THE NEXT NPAC LOW TO DEVELOP SOUTH OF THE CENTRAL
ALEUTIANS LATE TONIGHT. BEYOND 72 HOURS...MODELS DIVERGE SO KEPT
CHANGES MINIMAL BEYOND WEDNESDAY.

.ANALYSIS AND UPPER LEVELS...
MAIN FEATURE TODAY IS A RAPIDLY DEVELOPING LOW OVER THE WESTERN
ALEUTIANS AND THE ASSOCIATED FRONT ACROSS THE CENTRAL ALEUTIANS.
WINDS HAVE INCREASE TO HURRICANE FORCE NEAR ADAK. THE LOW WILL WEAKEN
TODAY BUT NOT BEFORE SENDING STORM FORCE WINDS TOWARD THE EASTERN
ALEUTIANS AND THE PRIBILOFS. UPPER RIDGE OVER THE EASTERN BERING WILL
RAPIDLY SHIFT EAST IN RESPONSE TO THE STRONG SYSTEM OUT WEST. THIS
WILL EVENTUALLY LEAD TO A SIGNIFICANT PATTERN CHANGE FOR SOUTH
CENTRAL ALASKA.

.SHORT TERM FORECAST...
SOUTHCENTRAL...
UPPER TROF FINALLY SWINGING THROUGH SOUTH CENTRAL EARLY THIS MORNING
GIVING ONE FINAL REINFORCING SHOT OF COLD AIR ACROSS THE REGION.
COLDEST TEMPERATURES OVER THE STATE REMAIN IN ALONG THE YUKON VALLEY
AND THE NORTH SLOPE. IN OUR DOMAIN...TEMPERATURES BELOW ZERO
EVERYWHERE EXCEPT COASTAL AREAS AND WHERE CLOUD COVER IS LIMITING
RADIATIVE COOLING. ONE MORE NIGHT OF SUB ZERO TEMPERATURES EXPECTED
TONIGHT BEFORE THE PATTERN CHANGE. A PERSISTENT FEATURE NEAR KACHEMAK
BAY CONTINUES TO BRING SNOW SHOWERS TO HOMER AND SELDOVIA.

COLD AIR ADVECTION FURTHER ENHANCING THE THERMAL GRADIENT RESULTING
IN GUSTY WINDS THROUGH THE GAPS. WHITTIER AND SEWARD WINDS WILL
INCREASE TODAY AS WELL AS ALONG THE ALASKA RANGE AS THE TROF AXIS
SHIFTS EASTWARD. WIND CHILL ADVISORIES IN EFFECT FOR THOMPSON PASS
AND BROAD PASS WHERE COLD TEMPERATURES AND WINDS GUSTING TO 30 MPH
WILL DROP WIND CHILLS TO 30 TO 45 BELOW ZERO.

MUCH ADVERTISED PATTERN SHIFT COMING MONDAY NIGHT AS THE REMNANTS OF
THE NPAC FRONT MOVE INTO THE GULF. A TRIPLE POINT LOW WILL FORM NEAR
KODIAK ISLAND WHILE TEMPERATURES CLIMB RAPIDLY BEHIND THE FRONTAL
BOUNDARY. KODIAK CITY WILL SEE TEMPERATURES CLIMB TO NEAR 40 DEGREES
WHILE SOUTH CENTRAL COASTAL AREAS STAY CLOSER TO THE FREEZING MARK.
THINKING ANCHORAGE BOWL AND THE MATSU VALLEY WILL SEE SOME OVER
RUNNING MOISTURE MONDAY NIGHT. THAT WILL BRING SOME SNOW INITIALLY
BEFORE SOUTHEAST WINDS DOWNSLOPE THE AREA...CUTTING OFF ANY
SIGNIFICANT SNOW ON TUESDAY. AFTER TUESDAY...MODELS DIFFER WILDLY SO
HAVE KEPT THE CHANCE OF SNOW FOR A FEW PERIODS BEFORE CLEARING IT OUT
LATER IN THE WEEK.

SOUTHWEST...
THE LOWER KUSKOKWIM VALLEY SEEING THE COLDEST TEMPERATURES THIS
MORNING WHILE BRISTOL BAY ZONE REMAINS BELOW ZERO FOR THE 11TH
STRAIGHT DAY. TEMPERATURES WILL MAKE A DRASTIC RECOVERY TO NEAR
FREEZING ALONG THE ALASKA PENINSULA BY MONDAY NIGHT AND TUESDAY. COLD
AIR WILL LIKELY BE DIFFICULT TO ERODE AT THE SURFACE INITIALLY SO
WILL HAVE TO CONSIDER THE THREAT OF FREEZING RAIN...STILL TOO FAR OUT
TO MENTION IN THE FORECAST BUT SOMETHING WE WILL BE WATCHING FOR.

IN ADDITION...THE KUSKOKWIM DELTA WILL LIKELY SEE BLIZZARD CONDITIONS
AS A SECOND LOW ENTERS THE EASTERN BERING AND INCREASES THE WINDS
FROM THE EAST MONDAY NIGHT. AT SOME POINT...A BLIZZARD WATCH MAY BE
NECESSARY IF THE MODELS CONTINUE TO LEAN TOWARD THAT SOLUTION.

BERING SEA AND ALEUTIANS...
THE WIND IS THE BIG STORY OUT WEST WITH A VIGOROUS SYSTEM DEVELOPING
TODAY. HIGH WIND WARNINGS PANNING OUT WITH ADAK PEAKING AT 74 KTS
EARLIER THIS MORNING. A BLIZZARD WATCH IS IN EFFECT FOR THE
PRIBILOFS. HELD OFF ON UPGRADING TO A WARNING AS UNSURE IF
TEMPERATURES WILL REMAIN COLD ENOUGH. WILL HAVE TO MAKE A DECISION IN
THE NEXT FEW HOURS AS CONDITIONS WOULD BEGIN BY THIS AFTERNOON. THE
WINDS WILL WEAKEN AS THE SYSTEM MOVES EAST BUT A SECOND LOW WILL
DEVELOP SOUTH OF THE CHAIN TONIGHT A BIT FURTHER EAST THAN THE FIRST
LOW...PUTTING IT NEAR THE PRIBILOFS MONDAY EVENING. WILL HAVE TO
CONSIDER HIGH WIND WATCH FOR THE CENTRAL ALEUTIANS DURING THIS TIME
FRAME.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING...187 191
         BLIZZARD WATCH...195
MARINE...HEAVY FREEZING SPRAY WARNING...120 121 125 129 130 132 138
             140 141 150 155 160 179 185
         HURRICANE FORCE WIND WARNINGS...172 411 412 413
         STORMS...170 175 176 179 185
         GALES...121 129 130 132 138 150 155 160 165 171 180
FIRE WEATHER...NONE.

AB JAN 08