Flash Flood Warning 4, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 PM AKDT THU MAR 26 2009

.MODEL DISCUSSION...NAM MODEL IS DOING BETTER WITH THE DETAILS OF THE
LOW IN THE NORTHERN GULF. MODELS ARE OTHERWISE IN GOOD AGREEMENT
THROUGH SATURDAY AFTERNOON. AFTER THAT THERE IS SOME DISAGREEMENT TOT
THE ACTUAL TRACK OF A STRONG LOW THAT WILL MOVE NEAR THE TIP OF THE
ALASKA PENINSULA. DIFFERENCES ARE NOT EARTH SHATTERING THOUGH AND WE
ARE GOING MOSTLY WITH THE GFS AS GUIDANCE.

.ANALYSIS AND UPPER LEVELS...UPPER LEVEL TROUGH IS SITUATED OVER
WESTERN ALASKA AND EXTENDING OVER THE PRIBILOF ISLANDS. THE POSITION
OF THIS UPPER LEVEL TROUGH WILL REMAIN MOSTLY UNCHANGED INTO THE
WEEKEND. AT THE SURFACE THE LOW CENTER IS NEAR MIDDLETON ISLAND AND
WILL MOVE OVER THE EASTERN KENAI PENINSULA TONIGHT AND THEN SLOWLY
MOVE TO THE COPPER RIVER BASIN FRIDAY AFTERNOON.
THE 250 MB JET IS RUNNING FROM THE SOUTHWEST AND IS REMAINING SOUTH
OF THE AREA RIGHT NOW. IT WILL MOVE INTO THE GULF ON SATURDAY AS IT
STRENGTHENS A LOW THAT WILL MOVE NEAR THE ALASKA PENINSULA SATURDAY
AND SATURDAY NIGHT.

.SHORT TERM FORECAST...BLIZZARD CONDITIONS ALONG THE ALASKA PENINSULA
SHOULD END BY EARLY THIS EVENING THOUGH THERE WILL BE SOME LOCALLY
REDUCED VISIBILITIES FROM BLOWING SNOW THROUGH THE NIGHT...BUT NOT AS
BAD AS IT HAS BEEN.
THE LOW NEAR THE NORTH GULF COAST IS KEEPING THE BARRIER JET IN TACK
THIS AFTERNOON. IT SHOULD DIMINISH THIS EVENING AND THEN DISSIPATE AS
THE LOW MOVES INTO THE EASTERN KENAI PENINSULA TONIGHT. PRECIPITATION
SHOULD TURN BACK TO ALL SNOW AS THIS SYSTEM OCCLUDES AND THE WARM AIR
HEADS SOUTH OF THE AREA. THERE IS AN INCREASED POTENTIAL FOR SNOW IN
THE ANCHORAGE AREA LATE TONIGHT THROUGH FRIDAY NIGHT WITH THE LATEST
TRACK OF THIS LOW.

.LONG TERM FORECAST...IT APPEARS AS THOUGH THE PATTERN OF THE NEXT
THREE DAYS REPEATS...WITH ANOTHER STRONG LOW MOVING INTO THE NORTHERN
GULF ON SUNDAY BEFORE EVENTUALLY MOVING ONSHORE AND INTO THE COPPER
RIVER BASIN SOMETIME THE FIRST HALF OF NEXT WEEK.  THE LACK OF HIGH
PRESSURE TO THE NORTH AND EAST WITH THIS SYSTEM MAY HELP TO KEEP
WINDS FROM BECOMING QUITE AS STRONG IN THE NORTHERN GULF WITH THIS
NEXT SYSTEM AS THEY WERE WITH THIS ONE.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD 181.
MARINE...GALE 120 125 150 155 170 172 175 176.
         HEAVY FREEZING SPRAY 155 165 179.
FIRE WEATHER...NONE.

MAR 09

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ANCHORAGE AK
820 PM AKDT THU MAR 26 2009

AKZ121-101-260600-

...VERY LIGHT ASHFALL POSSIBLE OVER KENAI PENINSULA...

LIGHT SNOW SHOWERS ARE CURRENTLY CROSSING THE NORTHERN KENAI
PENINSULA. RESIDUAL ASH FROM THIS MORNINGS ERUPTIONS OF MT REDOUBT
MAY FALL AS THEY MOVE OVERHEAD. THESE SHOWERS ARE EXPECTED TO MOVE
OVER THE COOK INLET AND THEN DISSIPATE. ASHFALL AMOUNTS ARE EXPECTED
TO BE A TRACE OR LESS.  ASHFALL IS NOT EXPECTED ALONG THE ROAD SYSTEM
OR IN THE ANCHORAGE BOWL.

SPECIAL WEATHER STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE ANCHORAGE AK
820 PM AKDT THU MAR 26 2009

AKZ121-101-270600-

...VERY LIGHT ASHFALL POSSIBLE OVER KENAI PENINSULA...

LIGHT SNOW SHOWERS ARE CURRENTLY CROSSING THE NORTHERN KENAI
PENINSULA. RESIDUAL ASH FROM THIS MORNINGS ERUPTIONS OF MT REDOUBT
MAY FALL AS THEY MOVE OVERHEAD. THESE SHOWERS ARE EXPECTED TO MOVE
OVER THE COOK INLET AND THEN DISSIPATE. ASHFALL AMOUNTS ARE EXPECTED
TO BE A TRACE OR LESS.  ASHFALL IS NOT EXPECTED ALONG THE ROAD SYSTEM
OR IN THE ANCHORAGE BOWL.

SPECIAL WEATHER STATEMENT...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
845 PM AKDT THU MAR 26 2009

AKZ121-101-270600-

...VERY LIGHT ASHFALL POSSIBLE OVER KENAI PENINSULA...

LIGHT SNOW SHOWERS ARE CURRENTLY MOVING ACROSS THE NORTHERN KENAI
PENINSULA AND THE ANCHORAGE AREA. RESIDUAL ASH FROM THIS MORNINGS
ERUPTIONS OF MT REDOUBT MAY FALL AS THEY MOVE OVERHEAD. THESE SHOWERS
ARE EXPECTED TO MOVE OVER THE COOK INLET AND THEN DISSIPATE. ASHFALL
AMOUNTS ARE EXPECTED TO BE A TRACE OR LESS.

SPECIAL WEATHER STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE ANCHORAGE AK
845 PM AKDT THU MAR 26 2009

AKZ121-101-270600-

...VERY LIGHT ASHFALL POSSIBLE OVER KENAI PENINSULA AND ANCHORAGE
AREA...

LIGHT SNOW SHOWERS ARE CURRENTLY MOVING ACROSS THE NORTHERN KENAI
PENINSULA AND THE ANCHORAGE AREA. RESIDUAL ASH FROM THIS MORNING'S
ERUPTIONS OF MT REDOUBT MAY FALL AS THEY MOVE OVERHEAD. THESE SHOWERS
ARE EXPECTED TO MOVE OVER THE COOK INLET AND THEN DISSIPATE. ASHFALL
AMOUNTS ARE EXPECTED TO BE A TRACE OR LESS.

SPECIAL WEATHER STATEMENT...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
1010 PM AKDT THU MAR 26 2009

AKZ121-101-111-145-271000-

...VERY LIGHT ASHFALL POSSIBLE FROM THE KENAI PENINSULA TO THE
SUSITNA VALLEY...

LIGHT SNOW SHOWERS ARE CURRENTLY MOVING FROM THE NORTHERN KENAI
PENINSULA TO THE MATANUSKA AND SUSITNA VALLEYS INCLUDING THE
ANCHORAGE BOWL. RESIDUAL ASH FROM THIS MORNINGS ERUPTIONS OF MT
REDOUBT MAY FALL AS THEY MOVE OVERHEAD. THESE SHOWERS ARE EXPECTED TO
MOVE OVER COOK INLET AND THEN DISSIPATE. ASHFALL AMOUNTS ARE EXPECTED
TO BE A TRACE OR LESS.

SPECIAL WEATHER STATEMENT...UPDATED
NATIONAL WEATHER SERVICE ANCHORAGE AK
1030 PM AKDT THU MAR 26 2009

AKZ121-125-101-111-145-271000-

...VERY LIGHT ASHFALL POSSIBLE FROM THE KENAI PENINSULA TO THE
SUSITNA VALLEY...

LIGHT SNOW SHOWERS ARE CURRENTLY MOVING FROM THE KENAI PENINSULA TO
THE MATANUSKA AND SUSITNA VALLEYS INCLUDING THE ANCHORAGE BOWL.
RESIDUAL ASH FROM THIS MORNINGS ERUPTIONS OF MT REDOUBT MAY FALL AS
THEY MOVE OVERHEAD. THESE SHOWERS ARE EXPECTED TO MOVE OVER COOK
INLET AND THEN DISSIPATE. ASHFALL AMOUNTS ARE EXPECTED TO BE A TRACE
OR LESS.