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000
FXAK68 PAFC 201322
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
522 AM AKDT SUN APR 20 2014

.ANALYSIS AND UPPER LEVELS...
SKIES CONTINUE TO CLEAR ACROSS MUCH OF THE SOUTHERN MAINLAND THIS
MORNING AS HIGH PRESSURE BUILDS OVER THE INTERIOR...WHILE A BROAD
AREA OF LOW PRESSURE CENTERED OVER THE SOUTHERN GULF CONTINUES TO
BRING STEADY RAIN TO KODIAK ISLAND. A TROUGH EXTENDING
NORTHWESTWARD FROM THE LOW INTO THE EASTERN BERING IS SUPPORTING
A MIX OF RAIN AND SNOW SHOWERS FROM THE ALASKA PENINSULA TO THE
EASTERN ALEUTIANS. FURTHER WEST...ANOTHER RIDGE IS BUILDING OVER
THE CENTRAL BERING AHEAD OF A STRONG NORTH PACIFIC LOW AND
ASSOCIATED FRONT APPROACHING THE WESTERN ALEUTIANS ACCOMPANIED BY
A WIDE SWATH OF PRECIPITATION AND GALE FORCE WINDS.

&&

.MODEL DISCUSSION...
MODELS REMAIN IN GOOD OVERALL SYNOPTIC AGREEMENT THROUGH THE
SHORT TERM AND HAVE ALSO COME INTO BETTER AGREEMENT WITH RESPECT
TO THE STRENGTH/TIMING OF VARIOUS WAVES ROTATING AROUND THE
NORTHERN PERIPHERY OF THE GULF LOW LATER THIS AFTERNOON. THE LOW
WILL GRADUALLY WEAKEN THROUGH MONDAY AS IT TRACKS TOWARDS THE
SOUTHEAST AND HIGH PRESSURE BECOMES BETTER ESTABLISHED OVER THE
MAINLAND. MEANWHILE...THE NORTH PACIFIC LOW APPROACHING THE
WESTERN ALEUTIANS WILL TRACK ALONG THE CHAIN THROUGH THE MIDDLE OF
THE WEEK BUT LIKELY REMAIN SOUTH OF THE MAINLAND AS IT ENCOUNTERS
THE BLOCKING HIGH CENTERED OVER THE INTERIOR. CONTINUED TO UTILIZE
THE EC GIVEN ITS CONSISTENCY OVER THE PAST SEVERAL DAYS.

&&

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...
RAIN ASSOCIATED WITH THE GULF LOW WILL REMAIN CONFINED MOSTLY TO
KODIAK ISLAND AND THE GULF WATERS...WITH PRECIPITATION TRENDING
DOWNWARD THROUGH MONDAY AS THE LOW SINKS SLOWLY SOUTHWARD AWAY
FROM THE AREA. A WEAK DISTURBANCE ROTATING THROUGH THE NORTHERN
GULF THIS AFTERNOON ON THE NORTHERN PERIPHERY OF THE LOW WILL
PROVIDE THE CHANCE FOR A FEW RAIN SHOWERS ALONG THE COAST AND ALSO
SERVE TO INCREASE GAP WINDS THROUGH FAVORABLE AREAS SUCH AS
TURNAGAIN ARM AND THE KNIK RIVER VALLEY. OTHERWISE...MAINLY DRY
CONDITIONS MARKED BY ABUNDANT SUNSHINE WILL PREVAIL ACROSS MUCH OF
THE AREA THROUGH THE EARLY PART OF THE WEEK AS HIGH PRESSURE
BECOMES BETTER ESTABLISHED OVER THE MAINLAND. WILL HAVE TO MONITOR
FIRE WEATHER POTENTIAL THROUGH THE MATANUSKA VALLEY THIS AFTERNOON
AS GUSTY KNIK WINDS COUPLED WITH LOW RELATIVE HUMIDITY VALUES
COULD LEAD TO CONDITIONS APPROACHING RED FLAG CRITERIA.

SOUTHWEST ALASKA...
THE REGION WILL SEE GRADUALLY CLEARING SKIES
THROUGHOUT THE DAY TODAY AS RIDGING OVER THE NORTHERN MAINLAND
CONTINUES TO BUILD SOUTHWARD. FURTHER SOUTH...RAIN SHOWERS ALONG
THE AKPEN WILL DISSIPATE THIS MORNING AND SKIES WILL BRIEFLY
CLEAR UNTIL A FRONT FROM THE ALEUTIAN LOW APPROACHES ON TUESDAY.
THERE IS BETTER AGREEMENT IN THE MODELS NOW THAT THIS FRONT WILL
STRUGGLE TO REACH VERY FAR INLAND...MEANING THAT INTERIOR
LOCATIONS OF BRISTOL BAY AND THE KUSKOKWIM DELTA WILL LIKELY STILL
SEE PARTLY CLOUDY SKIES AND ABOVE NORMAL TEMPERATURES INTO MID
WEEK. AHEAD OF THE ALEUTIAN LOW...A WEAK UPPER TROUGH CURRENTLY
OVER THE CENTRAL BERING WILL MIGRATE TOWARDS THE KUSKOKWIM DELTA
AND BRING A SLIGHT CHANCE OF RAIN AND SNOW SHOWERS TO THE AREA
OVERNIGHT TONIGHT.

BERING SEA/ALEUTIANS...
CONDITIONS THROUGHOUT THE WESTERN AND
CENTRAL ALEUTIANS WILL QUICKLY DETERIORATE OVER THE COURSE OF
THIS MORNING AS THE FRONT AHEAD OF THE ALEUTIAN LOW APPROACHES.
THE STRONG GALE FORCE FRONT THAT ACCOMPANIES THIS LOW WILL BRING
WIDESPREAD RAINS AND STRONG WIND GUSTS TO THE WESTERN AND CENTRAL
ALEUTIANS TODAY. THIS FRONT WILL REACH THE PRIBILOFS AND AKPEN ON
MONDAY MORNING BEFORE DIMINISHING CONSIDERABLY IN INTENSITY ON
MONDAY AFTERNOON. THE ENTIRE SYSTEM WILL THEN STALL OUT AND SLOWLY
DISSIPATE OVER THE CENTRAL BERING AND ALEUTIANS ON TUESDAY...WHICH
WILL BRING CLOUDS AND RAIN TO THE ENTIRE REGION THROUGH MID WEEK.

&&

.LONG TERM FORECAST...
WHILE THERE HAS NOT BEEN A LARGE CHANGE IN THE LONG TERM
FORECAST...THE MODELS ARE BEGINNING TO STRUGGLE LATE THIS WEEK
WITH THE TRACK OF THE NEXT LOW THROUGH THE ALEUTIANS. THE GENERAL
PATTERN OF RIDGING OVER MOST OF THE MAINLAND AND LOWS OVER THE
BERING OR NORTH PACIFIC WILL REMAIN MOSTLY INTACT...BUT THE DEVIL
STILL REMAINS IN THE DETAILS. THE MODELS ARE STRUGGLING WITH HOW
FAR NORTH INTO THE PACIFIC THAT THE MAINLAND RIDGE WILL ALLOW AN
ALEUTIAN LOW TO TRAVEL THIS WEEKEND...SO RAIN FOR THE GULF COAST
CANNOT BE RULED OUT THIS WEEKEND. IT DOES STILL APPEAR THAT THE
INTERIOR SOUTHERN MAINLAND WILL REMAIN MOSTLY CLEAR AND DRY FOR
THE NEXT WEEK.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE
MARINE...GALE WARNING 119 120 131 132 155 170 172 173 174 175 176
  177 178
FIRE WEATHER...NONE

&&

$$

CB/DEK APR 14