Small Craft Advisory 83, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
130 PM AKST FRI JAN 25 2013

.MODEL DISCUSSION...OK THROUGH MOST OF SUNDAY THEN THERE'S SIGNIFICANT
DISAGREEMENT LATE SUN AND INTO THE NEXT WEEK. PREFER THE NAM WHICH BRINGS
ANOTHER UPPER IMPULSE DOWN FROM THE ARCTIC LATE SAT EVENING AND SUNDAY
WHICH WILL KEEP THE COLD AIR LOCKED IN PLACE ACROSS SOUTHERN ALASKA NORTH
OF 57N THROUGH EARLY MONDAY. BEYOND THAT, THE PATTERN WILL MOST CERTAINLY
BREAK BACK INTO ONE OF WARMER AND WETTER CONDITIONS AS A SURFACE LOW
TRACKS NORTHWARD ACROSS THE ALASKA PENINSULA AND WESTERN BRISTOL BAY. THE
QUESTION IS WHEN THIS WILL TAKE PLACE.

.ANALYSIS AND UPPER LEVELS...UPPER LEVEL TROF HAS PUSHED THE ARCTIC FRONT
INTO THE GULF. AT MIDDAY FRIDAY THIS BOUNDARY LIES FROM NORTHERN AFOGNAK
ISLAND EAST NORTHEAST TO CAPE YAKATAGA. SURFACE LOW NEAR MIDDLETON ISLAND
THIS AFTERNOON WILL MOVE TO 140W SAT EVENING AND BECOME NEARLY STATIONARY
AND WEAKEN ON INTO MONDAY.

.SHORT TERM FORECAST...SNOW ENDING FROM NORTHWEST TO SOUTHEAST. ANOTHER
1-3 INCHES ZONE 141 BUT THE WRANGELL MOUNTAINS AND UP SLOPE AREAS OF THAT
EASTERN ZONE WILL SEE A LITTLE MORE SINCE IT WILL TAKE LONGER TO END DUE
TO PERSISTENT CYCLONIC WESTERLY FLOW. STRONG NORTH WINDS WORKING INTO THE
NORTHERN SUSITNA VALLEY WILL SPREAD TO THE SOUTHERN AREAS AND NORTHERN
COOK INLET TONIGHT. GUSTS TO 50 MPH MAY OCCUR FROM WASILLA NORTHWARD. THE
FORECAST PROBLEM IS HOW LONG, AND HOW FAR SOUTH THE STRONGER WINDS WILL
LAST. I WOULD LIKE TO SEE BETTER UPPER SUPPORT BUT 50 MPH FOR THE WINDIER
AREAS OF THE SUSITNA, AND EVEN MATANUSKA VALLEY, LOOKS REASONABLE.

GROUND BLIZZARD THOMPSON PASS LOOKS GOOD BEGINNING AROUND MIDNIGHT.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BIZZARD WARNING ZONE 131 THROUGH THOMPSON PASS BEGINNING
MIDNIGHT. WINDCHILL ADVISORY SUSITNA VALLEY TONIGHT.
MARINE...GALES...AREAS...121 127 128 129 130 175 176 185.
HEAVY FREEZING SPRAY...AREAS...121 126 127 128 129 138 140 160 185.
FIRE WEATHER...NONE.

D PERCY JAN 13