High Wind in Alaska, February 10, 2014

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
335 PM AKST SUN FEB 9 2014

.SHORT TERM...SUNDAY NIGHT THROUGH MONDAY NIGHT. COLD AND WINDY
CONDITIONS WILL BE THE MAIN THEME FOR THE PANHANDLE OVER THE NEXT
36 HOURS. A DEVELOPING WAVE OF LOW PRESSURE WILL BRING SNOW TO
THE SOUTHERN PANHANDLE BEGINNING MONDAY MORNING AND CONTINUING
INTO THE EVENING HOURS. HIGH PRESSURE OVER THE YUKON AND THE LOW
PRESSURE SYSTEM IN THE GULF WILL LEAD TO A VERY STRONG
NORTHEASTERLY PRESSURE GRADIENT OVER THE PANHANDLE.

OUTFLOW WINDS WILL BE STRENGTHENING THROUGH THE PERIOD AS THE
GRADIENT INCREASES. NORTHERLY WINDS OVER THE NORTHERN INNER
CHANNELS WILL CONTINUE TO STRENGTHEN TONIGHT AND INTO MONDAY WITH
GALE FORCE WINDS DEVELOPING IN MOST AREAS. THIS WILL ALSO LEAD TO
THE DEVELOPMENT OF FREEZING SPRAY WITH SOME HEAVY FREEZING SPRAY
IN THE FAR NORTHERN INNER CHANNELS. LOCALLY WINDY CONDITIONS WILL
BE FELT NEAR INTERIOR PASSES AND HAVE INCLUDED STRONG WIND
HEADLINES FOR THIS. BASED ON LATEST MODEL GUIDANCE UPGRADED THE
HIGH WIND WATCH TO A WARNING FOR JUNEAU AS TAKU WIND SETUP STILL
APPEARS TO BE VERY FAVORABLE WITH STRONG CROSS BARRIER FLOW, A
STRENGTHENING INVERSION AND GOOD FLOW REVERSAL AT AROUND 500-600
MB. GUSTS TO 60 MPH ARE EXPECTED TO BEGIN TO DIMINISH DURING
MONDAY EVENING. THESE COLD WINDS WILL DRIVE ANOTHER SURGE OF
ARCTIC AIR INTO THE PANHANDLE WITH TEMPERATURES STRUGGLING TO GET
OUT OF THE TEENS SUNDAY OVER THE NORTHERN PANHANDLE. LOWS WILL
FALL WELL INTO THE SINGLE DIGITS FOR MANY OF THE WIND SHELTERED
LOCATIONS.

AS THE LOW PRESSURE SYSTEM MOVES TOWARD THE SOUTHERN PANHANDLE
EXPECT SNOW TO INCREASE THROUGH THE DAY ON MONDAY. HAVE ISSUED A
WINTER WEATHER ADVISORY FOR ZONE 28 WITH EXPECTED ACCUMULATION OF
2 TO 5 INCHES BY MONDAY NIGHT. THERE HAS BEEN SOME MODEL
DISAGREEMENT ON EXACTLY HOW FAR NORTH THE PRECIPITATION SHIELD
WILL GET BUT OPTED TO GO WITH THE FARTHER NORTH SOLUTION THAT THE
ECMWF HAS BEEN SHOWING FOR THE PAST FEW DAYS. THE HYDER AREA CAN
ALSO EXPECT ACCUMULATION AROUND 3-6 INCHES WHICH FALLS SHORT OF
ADVISORY CRITERIA. SNOW WILL TAPER OFF LATER MONDAY EVENING AS THE
SYSTEM WEAKENS.

USED A BLEND OF THE 12Z NAM/00Z ECMWF FOR UPDATES TO THE FORECAST
FOR THE NEXT 36 HOURS. FORECASTER CONFIDENCE IS ABOVE AVERAGE ON
COLD AND VERY WINDY CONDITIONS. CONFIDENCE DECREASES A BIT ON THE
NORTHWARD EXTENT OF THE SNOW OVER THE SOUTHERN PANHANDLE.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...THE MONDAY LOW OVER THE
DIXON ENTRANCE/HECATE STRAIT AREA WILL HAVE WEAKENED AND MOVED OFF
TO THE EAST BY TUESDAY MORNING. HOWEVER ANOTHER LOW WILL FOLLOW IN ITS
PATH TUESDAY AND BRING MORE PRECIP TO THE SOUTHERN HALF OF THE
PANHANDLE THROUGH TUESDAY NIGHT. EXPECT A MIX OF RAIN AND SNOW FOR
THE EXTREME SOUTHERN TOWNS OF HYDABURG AND METLAKATLA AND MAINLY
SNOW NORTHWARD. HAVE ANOTHER 2-5 INCHES FOR THOSE SOUTHERN ZONES
TUESDAY THROUGH TUESDAY NIGHT. ONCE AGAIN THE NORTHERN EXTENT OF
THE PRECIP IS IN QUESTION. HAVE A SLIGHT CHANCE OF SNOW GETTING AS
FAR NORTH AS ANNETTE AND ALMOST TO TAKU INLET. AS IN THE SHORT
TERM SECTION THE LOW PASSING TO THE SOUTH WILL CAUSE A SLIGHT RE-
SURGE OF NORTHERLY OUTFLOW WINDS...BUT NOT EXPECTING ANOTHER TAKU
TYPE EVENT.

ANOTHER LOW PRESSURE SYSTEM MOVES INTO THE NORTHERN GULF WEDNESDAY
NIGHT INTO THURSDAY. THE FRONTAL BAND WILL BRING SNOW LIKELY TO
THE COASTAL AREAS FIRST AND THEN MOVE INLAND. PATTERN LOOKS TO
REMAIN ACTIVE THERE AFTER WITH ANOTHER LOW MOVING UP FROM THE
SOUTH TOWARD THE END OF THE WEEK AND BECOMING WRAPPED UP INTO THE
NORTHERN LOW.

HOWEVER...MODELS HAVE SHOWN A LOT OF VARIABILITY IN THE LAST FEW
RUNS WITH THESE LOWS MOVING ACROSS THE GULF THROUGH THE NEXT
WEEK. THIS HAS CREATED A LOT OF UNCERTAINTY AND LOWER FORECAST
CONFIDENCE IN THE TIMING OF FRONTS AND THUS SNOW. IN THE NEAR TERM
USED A BLEND OF AVAILABLE MODELS THEN KEPT THE PRESSURE FIELD
THROUGH THE LAST PART OF THE FORECAST SO AS TO NOT BE FLIP
FLOPPING WITH EACH NEW MODEL SOLUTION. DID BACK OFF ON POPS SLIGHTLY DUE
TO THE UNCERTAINTY.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...HIGH WIND WARNING FROM 6 AM TO 9 PM AKST MONDAY FOR AKZ025.
         STRONG WIND FROM MIDNIGHT AKST TONIGHT THROUGH MONDAY AFTERNOON
     FOR AKZ022.
         WINTER WEATHER ADVISORY FROM 9 AM TO 9 PM AKST MONDAY FOR AKZ028.
         STRONG WIND THROUGH MONDAY AFTERNOON FOR AKZ018-019.
         WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 4 PM AKST MONDAY
     FOR AKZ018.
         STRONG WIND FROM 6 PM AKST THIS EVENING THROUGH MONDAY AFTERNOON
     FOR AKZ017.
MARINE...HEAVY FREEZING SPRAY WARNING FOR PKZ011.
         HEAVY FREEZING SPRAY WARNING FOR PKZ013-031.
         HEAVY FREEZING SPRAY WARNING FOR PKZ012.
         STORM WARNING FOR PKZ012.
         GALE WARNING FOR PKZ011-013-021-022-031>036-043-051-052.
         SMALL CRAFT ADVISORY FOR PKZ041-042-053.

&&

TPS/FERRIN