862
FXAK67 PAJK 160303 CCA
AFDAJK
SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
332 PM AKST SUN DEC 15 2024
SHORT TERM
/ THROUGH MONDAY NIGHT / BLOCKING PATTERN IN PLACE
ACROSS SOUTHEAST ALASKA AND THE EASTERN GULF. WEATHER WISE A
LITTLE BIT OF OVER THE TOP OF THE RIDGE LIGHT PRECIPITATION TO THE
NORTHEAST GULF COAST. LOW LEVEL MOISTURE AROUND THE NORTHERN
PANHANDLE THAT HAS NOT MIXED OUT DROPPING FLURRIES OR FREEZING
DRIZZLE.
A FRONT WILL BE APPROACHING FROM THE SOUTHWEST BUT WILL KEEP JUST
OFF SHORE ACCORDING THE FORECAST MODELS. WITH NO STRONG SYSTEMS IN
THE AREA, WIND ARE ON THE LIGHTER SIDE, BUT WILL START TO INCREASE
LATE MONDAY TO NEAR 25 KT AS THE GRADIENT INCREASES.
LONG TERM.../TUESDAY TO FRIDAY NIGHT/
MAIN STORY FOR THE MID
RANGE IS THAT OUTFLOW WINDS WILL CONTINUE TO PICK UP IN LYNN
CANAL AS THE GRADIENT TIGHTENS WITH HIGH PRESSURE OVER THE
INTERIOR AND AN APPROACHING SURFACE LOW IN THE GULF MIDWEEK WHICH
WILL BRING SOME SNOW AND EVENTUALLY RAIN TO THE PANHANDLE. EXPECT
STRONGEST WINDS FOR THE INNER CHANNELS TUESDAY INTO WEDNESDAY,
PARTICULARLY LYNN CANAL AND INTO ICY STRAIT AND CROSS SOUND.
NOW FOR SOME DETAILS: A LARGE SCALE LOW WILL ENTRENCH ITSELF OVER
THE NORTH PACIFIC, BERING SEA, AND WESTERN GULF OF ALASKA BY
EARLY TO MIDWEEK. MULTIPLE SMALLER CIRCULATIONS WILL BE SPINNING
ABOUT THIS LARGE SCALE FEATURE THROUGHOUT THE WEEK. A FRONTAL BAND
FROM ONE OF THESE FEATURES WILL APPROACH THE PANHANDLE ON
WEDNESDAY. SWEEPING NORTH, IT WILL LIKELY SPREAD PRECIPITATION
OVER THE SOUTHERN HALF OF THE PANHANDLE WEDNESDAY AND THEN LIKELY
TOWARDS THE NORTHERN PANHANDLE WEDNESDAY NIGHT. WITH SUCH AN
ACTIVE PATTERN, THERE REMAINS LARGE SPREAD IN MODEL GUIDANCE IN
THE PATH OF THESE SMALLER LOWS MOVING INTO THE GULF. SOME
SOLUTIONS HAVE THIS FEATURE TAKING A MORE SOUTHERLY COURSE AND
DECAYING WHILE MOVING INLAND OVER POW AND KETCHIKAN. OTHERS HAVE
IT REMAINING FURTHER WEST IN THE GULF AND DIMINISHING, BUT
ALLOWING THE FRONT EXTENDING FROM IT TO OVERSPREAD PRECIPITATION
FURTHER NORTHWARD. IN BOTH SCENARIOS, THE HIGHEST LIKELIHOOD FOR
PRECIPITATION REMAINS THE SOUTHERN PANHANDLE. WITH THE COLDER
TEMPERATURES IN PLACE, INITIAL PRECIPITATION WILL LIKELY FALL AS
SNOW OR A RAIN SNOW MIX. FREEZING RAIN CANNOT BE RULED OUT WITH
THIS FEATURE AS COLD AIR WILL BE IN PLACE AND MAY LEAD TO
OVERRUNNING INITIALLY.
ACTIVE WEATHER WILL CONTINUE AT THE END OF THE WORK WEEK AND INTO
THE WEEKEND WITH WARMER MOIST SOUTHERLY FLOW LIKELY FOR THE
SOUTHERN PANHANDLE AS MULTIPLE SYSTEMS CONTINUE TO ROTATE THROUGH
THE GULF.
AVIATION
MAIN CONCERN FOR THIS TAF ISSUANCE IS THE FREEZING
DRIZZLE/WINTRY MIX AROUND THE LYNN CANAL AREA, FROM MUD BAY TO
AROUND THE JUNEAU AREA AS WELL AS GLACIER BAY. PRECIPITATION IS
DWINDLING DOWN ON THE NE GULF COAST WITH VFR CONDITIONS TO FOLLOW
THIS EVENING. ALL AREAS OF THE PANHANDLE LOOK TO TRANSITION TO VFR
BY TOMORROW MORNING, WITH MORE DRY AIR MOVING INTO THE PANHANDLE
AND NO MOISTURE FEED AVAILABLE TO KEEP CLOUDS IN PLACE.
MARINE
OUTFLOW PATTERN FORMING, WINDS IN LYNN CANAL
SLOWLY INCREASING MONDAY BEFORE INCREASING TUESDAY UP THROUGH SMALL
CRAFT TO GALE FORCE. SEAS BECOMING 'FULLY DEVELOPED' MEANING MORE
THAN THE STANDARD RULE OF THUMB OF 1 FOOT PER 5 KT WINDS BY LATE
TUESDAY. WITH LOW PRESSURE PERSISTING OVER THE GULF EXPECT SPEEDS TO
PICK UP THE 25 TO 35 KT THERE AS WELL MIDWEEK AS STRONGER FRONT
MOVES TO THE EASTERN PORTION OF THE GULF OF ALASKA.
AJK WATCHES/WARNINGS/ADVISORIES
PUBLIC...WINTER WEATHER ADVISORY UNTIL MIDNIGHT AKST TONIGHT FOR AKZ325.
MARINE...SMALL CRAFT ADVISORY FOR PKZ641>644-661>664-671-672.
SHORT TERM...BEZENEK
LONG TERM....SJ
AVIATION...NC
MARINE...BEZENEK
VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page