Freeze Warning 1, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
200 PM AKDT SAT SEP 14 2013

.ANALYSIS AND UPPER LEVELS...
THERE IS AN UPPER LEVEL LOW OVER THE CENTRAL GULF OF ALASKA. THERE
IS ANOTHER LOW OVER THE NORTHWEST BERING SEA. A RIDGE IN BETWEEN
THESE TWO LOWS IS OVER THE EASTERN BERING SEA/EASTERN ALEUTIANS AND
IS NOSING INTO SOUTHERN ALASKA. THE UPPER LEVEL PATTERN IS HIGHLY
AMPLIFIED AND THUS FAIRLY SLOW MOVING.

.MODEL DISCUSSION...
NOT AS MUCH AGREEMENT AMONGST THE NUMERICAL MODELS AS HAS BEEN THE
CASE FOR THE LAST FEW DAYS. ALTHOUGH ALL THE MODELS SEEM TO HAVE A
DECENT HANDLE ON THE OVER-ALL PATTERN...THEY ALL HAVE DIFFERENCES
ON THE LOCATION/ORIENTATION OF SURFACE LOWS AND THE TIMING/POSITION
OF FRONTS. FORECAST CONFIDENCE IS THUS NEAR NORMAL.

.SHORT TERM FORECAST...
FOR SOUTH CENTRAL AND SOUTHWEST ALASKA...THE CENTRAL GULF LOW WILL
SLIDE INTO THE EASTERN GULF THROUGH MONDAY. THE UPPER RIDGE WILL
STRENGTHEN OVER SOUTHERN ALASKA AND MAKE FOR A DRY SUNDAY AND
MONDAY OVER MOST OF THE AREA. LATER MONDAY THE NORTHWEST BERING LOW
WILL HAVE MOVED EAST ACROSS THE BERING SEA. THIS WILL BRING A CHANCE
OF RAIN ALONG THE SOUTHWEST COAST UNTIL THE LOW MOVES SOUTHEAST INTO
THE WESTERN GULF ON TUESDAY. PARTLY IN RESPONSE TO THIS THE EASTERN
GULF LOW WILL BEGIN TO CURVE NORTH MONDAY NIGHT AND NORTHEAST ON
TUESDAY. THIS WILL BRING A CHANCE OF RAIN INTO SOUTH CENTRAL ALASKA
FROM THE EAST ON MONDAY NIGHT AND TUESDAY.

FOR THE BERING SEA AND ALEUTIANS...THE NORTHWEST BERING LOW WILL
SLOWLY WORK ITS WAY ACROSS THE NORTHERN BERING SEA SUNDAY AND
MONDAY...THEN ACCELERATE SOUTHEAST INTO THE GULF OF ALASKA LATE
MONDAY NIGHT. THIS IS NOT A STRONG SYSTEM AND THE WINDS AND
PRECIPITATION WILL BE FAIRLY LIGHT FOR THIS AREA THIS TIME OF YEAR.
A SHORT-WAVE RIDGE WILL BUILD BEHIND THIS LOW INTO THE CENTRAL
BERING SEA ON TUESDAY. ALSO ON TUESDAY...A VERY DEEP LOW WILL HAVE
MOVED WEST FROM RUSSIA TO NEAR THE KAMCHATKA PENINSULA. THE WESTERN
ALEUTIANS WILL SEE THE INITIAL WARM FRONT FROM THIS SYSTEM MONDAY
NIGHT...AND THE COLD FRONT ON TUESDAY AFTERNOON.

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

LUDWIG SEP 13