806
FXAK67 PAJK 111823
AFDAJK
SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
1023 AM AKDT TUE AUG 11 2026
UPDATE
UPDATE FOR THE 18Z TAF ISSUANCE AND FOR THE SUICIDE
BASIN STARTING TO OVERTOP.
SYNOPSIS...
KEY MESSAGES:
- SUICIDE BASIN GLACIER DAMMED LAKE AND REACHED CAPACITY AND IS
STARTING TO OVERTOP. IN THE PAST, IT HAS TAKEN UP TO 6 DAYS FOR
A RELEASE AND MAIN FLOODING EVENT TO START AFTER THE BASIN IS
FULL. VISIT WEATHER.GOV/AJK/SUICIDEBASIN FOR MORE INFORMATION.
- WARMING TREND FOR THE WEEK WITH HIGHS IN THE 70S. LOWER 80S
WILL BE POSSIBLE, ESPECIALLY ACROSS INTERIOR LOCATIONS ACROSS
THE SOUTH AND FAR NORTH INTERIOR FOR MID TO LATE WEEK.
- THE WARM AND DRY CONDITIONS WILL BRING ELEVATED THREAT FOR FIRE
STARTS ACROSS MUCH OF SE AK. A FEW SMALL FIRES HAVE BEEN
OBSERVED ALREADY OVER THE PAST WEEK.
SHORT TERM.../THROUGH WEDNESDAY NIGHT/...
MORE BENIGN WEATHER PATTERN CONTINUES WITH HIGH PRESSURE SITTING
OVER THE GULF, KEEPING GENERALLY WARMER TEMPERATURES AND DRIER
WEATHER ACROSS THE PANHANDLE. THIS ALSO HAS BEEN ALLOWING FOR WEAK
ONSHORE FLOW AND MARINE LAYER CLOUD DEVELOPMENT ALONG THE OUTER
COASTLINE NEAR CROSS SOUND AND OVER COASTAL PARTS OF THE SOUTHERN
PANHANDLE THIS MORNING. THIS SHOULD BEGIN TO CLEAR OUT BY LATER
THIS MORNING, WITH MUCH OF THE PANHANDLE BEGINNING TO SEE BREAKS
IN THE CLOUDS BY MIDDAY AND CLEARING THROUGH TONIGHT. OVERALL
EXPECTING THE DRYING AND WARMING TREND TO CONTINUE, WITH SLIGHT
CHANCES FOR ISOLATED LIGHT SHOWERS AND DRIZZLE TODAY. THE HIGHEST
CHANCES REMAIN NEAR THE BORDER ALONG THE KLONDIKE AND HAINES
HIGHWAYS, ALONGSIDE VERY LOW CHANCES STILL OF ISOLATED
THUNDERSTORM DEVELOPMENT DURING THE AFTERNOON HOURS. RAIN CHANCES
WILL DIMINISH EVEN FURTHER INTO TONIGHT, TO NEARLY 0% BY WEDNESDAY
ACROSS MUCH OF THE PANHANDLE.
THE CLEARING SKIES AND BUILDING HIGH PRESSURE WILL BRING HIGH
TEMPERATURES IN THE MID 60S TO MID 70S TODAY, WITH SOME POCKETS OF
WARMER TEMPERATURES INTO THE HIGH 70S FURTHER INLAND GIVEN THE
CLEARING SKIES. PARTS OF HAINES HIGHWAY PAST KLUKWAN MAY EVEN SEE
SOME TEMPERATURES REACHING NEAR 80 TODAY AT THEIR HIGHEST, HOWEVER
THESE WON'T BE WIDESPREAD NOR ARE THEY EXPECTED TO LAST LONG. ANY
OTHER POCKETS OF HIGHER TEMPERATURES WILL BE FOR MORE INLAND
AREAS WITH CLEAR SKIES. THE HIGHER POTENTIAL FOR MORE WIDESPREAD
WARMER TEMPERATURES, WITH HIGHS IN THE UPPER 70S TO LOW 80S, ARE
NOT EXPECTED TO BE UNTIL LATER IN THE WEEK AS THE RIDGE OF HIGH
PRESSURE STRENGTHENS. SEA BREEZES WILL ALSO BEGIN TO DEVELOP
DURING THE DAYTIME AS THE SKIES CLEAR AND TEMPERATURES BEGIN TO
WARM BY THE AFTERNOON TO EVENING, WITH 15-20 KT GUSTS POSSIBLE FOR
AREAS ALONG THE WATER.
LONG TERM.../THURSDAY THROUGH SUNDAY NIGHT/...
PRIMARY FOCUS CONTINUES TO BE ON WARM/DRY THROUGH THE END OF THE
WEEK ALONG WITH THE UNCERTAINTY OF EQUATORIAL TROPICAL STORMS AND
SUBSEQUENT MOISTURE TRANSPORT INTO THE N/PAC. STARTING OFF, FOR
THE END OF THE WEEK CLUSTERS STILL SHOW STRONG AGREEMENT IN A
RIDGE DOMINATING THE WESTERN SEABOARD, LIMITING MAJOR SURFACE LOWS
FROM MOVING INTO THE GULF AND SERVING AS THE SOURCE FOR
ABNORMALLY WARM TEMPERATURES ALOFT. LREF 850MB TEMPERATURE
HISTOGRAMS HAVE SHIFTED TO MORE NORMAL DISTRIBUTION, TRANSLATING
TO INCREASED CONFIDENCE FOR 12C TO 14C AT 5000FT BY THUR/FRI. FOR
FOLKS AT SEA LEVEL, THIS MEANS WARM TEMPERATURES, WITH AFTERNOON
HIGHS LIKELY IN THE MID-70S TO MID-80S, DEPENDING ON WHERE YOU ARE
IN THE PANHANDLE. THUNDERSTORMS MIGHT MAKE AN APPEARANCE THUR/FRI
ACROSS THE CENTRAL AND SOUTHERN AREA; HOWEVER, THIS WILL
ULTIMATELY DEPEND ON WHERE THE RIDGE AXIS SETS UP AND A SHORTWAVE
MOVING DOWN FROM CANADA ALONG THE COAST RANGE, SOMETHING TO WATCH.
MOVING THROUGH THE WEEKEND GUIDANCE BREAKS DOWN THE RIDGE
SUGGESTING COOLER TEMPERATURES AND SOME MOISTURE; HOWEVER,
GUIDANCE CONTINUES TO BREAK DOWN THE RIDGE TOO SOON. THINKING WE
HOLD ON TO WARMER TEMPERATURES INTO SATURDAY, WITH COOLER
TEMPERATURES AND MOISTURE ARRIVING BY LATE SUNDAY AND/OR START OF
NEXT WEEK. WITH THAT SAID, THERE ARE A VARIETY OF OUTCOMES IN
VARIOUS ENSEMBLE SYSTEM SOLUTIONS; CURRENT FORECAST MONDAY
AFTERNOON STICKS WITH TROUGHING SETTING UP IN THE GULF AND AN
INCREASE IN CLOUDS AND LIGHT RAIN.
FOR THE MARITIME ENVIRONMENT, ANTICIPATE NORTHWEST WINDS TO
CONTINUE ALONG THE COAST, WITH DAILY SEA BREEZES MOVING THROUGH
THE INSIDE, PEAK AFTERNOON SPEEDS LIKELY MODERATE TO FRESH
BREEZES. BY SUNDAY/MONDAY NORTHWEST WINDS ALONG THE COAST GIVE WAY
TO SOUTHERLIES AS A SERIES OF LOWS MOVES INTO THE GULF. WILL NEED
TO WATCH FOR THE POTENTIAL FOR FRESH TO STRONG BREEZES ALONG THE
NORTHERN COAST.
AVIATION.../THROUGH WEDNESDAY MORNING/...
SURFACE HIGH OUT IN THE CENTRAL GULF CONTINUES TO BRING MARINE
LAYER OVER MUCH OF SEAK. ACROSS THE NORTHERN SITES, MARINE LAYER
WILL DISSIPATE WITH SKIES BECOMING SCT-BKN AOA 4KFT THIS
AFTERNOON. FOR PAYA, MARINE LAYER LINGERS WITH MVFR CIGS
CONTINUING THROUGH THE PERIOD. ACROSS THE SOUTH, CIGS IMPROVING
THIS AFTERNOON, BUT MARINE LAYER EXPECTED TO DEVELOP OVERNIGHT,
AT PAKW, PAKT AND PASI, WITH MVFR TO POSSIBLY IFR CIGS DEVELOPING.
WINDS ARE PRIMARILY SEA-BREEZE DRIVEN, EXPECTED TO INCREASE
THROUGH THE AFTERNOON AND INTO THE EVENING REACHING, BUT GENERALLY
STAYING AROUND 10KT OR LESS. HOWEVER, PAGY WILL INCREASE EACH
AFTERNOON/EVENING 10-15G20-25KT. PAKW AND PAKT ALSO LOOK TO
INCREASE WEDNESDAY AFTERNOON 10-15KT. NO LLWS CONCERNS THROUGH
THE TAF PERIOD.
MARINE...
OUTSIDE: OVERALL MARINE FORECAST AND WEATHER PATTERN REMAINS THE
SAME AS PREVIOUS DAYS. A 1023MB HIGH PRESSURE OVER THE CENTRAL
GULF EXPANDS AND STRENGTHENS TO 1028MB THROUGH END OF THE WEEK AS
IT MOVES OVER THE PANHANDLE. WAVE HEIGHTS REMAIN LARGELY BENIGN
THROUGH THE WEEK, AROUND 3 TO 5FT ALONG THE COAST WITH A
PERSISTENT SOUTHERLY SWELL OF 2FT OR LESS. ACCOMPANYING THIS HIGH
PRESSURE IS BROAD WESTERLY TO NORTHWESTERLY WINDS IN THE NE GULF
COAST FROM CAPE SPENCER DOWN TO DIXON ENTRANCE. WINDS GENERALLY
REMAINS AROUND 15 KTS OR LESS, WITH THE STRONGEST WINDS EXPECTED
IN THE VICINITY OF CAPE DECISION TO DIXON ENTRANCE UP TO 20KTS
THROUGH WEDNESDAY AFTERNOON. MAIN MARINE CONCERN FOR OUTER AND
COASTAL WATERS WILL BE NIGHTLY RETURN OF MARINE LAYER, DROPPING
VISIBILITIES POTENTIALLY AS LOW AS ONE QUARTER MILE EACH MORNING.
INSIDE: CONDITIONS ACROSS THE INSIDE WATERS REMAIN RELATIVELY
BENIGN THIS MORNING WITH WINDS LARGELY 10KTS OR LESS. ISOLATED
SPOTS ACROSS EASTERN ICY STRAIT FROM SISTERS TO ROCKY ISLAND
SEEING THE STRONGEST WINDS OF THE MORNING, AROUND 15KTS. MAIN
HAZARD THIS MORNING IS AN AREA OF DENSE FOG NEAR THE ENTRANCE OF
CROSS SOUND, WITH VISIBILITIES 1NM OR LESS AS EVIDENT BY FAA
WEBCAMS NEAR CAPE SPENCER. LIGHT TO MODERATE BREEZES EXPECTED ONCE
AGAIN THIS AFTERNOON AS HIGH PRESSURE CONTINUES TO INFLUENCE THE
AREA. STRONGEST INNER CHANNEL WINDS UP TO 15 TO 20 KTS ARE
EXPECTED FOR THE AFTERNOON AND EVENING HOURS AS SEA BREEZES
INCREASE IN STRENGTH BEFORE DIMINISHING DURING THE OVERNIGHT
HOURS.
HYDROLOGY...
SUICIDE BASIN GLACIER DAMMED LAKE AND REACHED CAPACITY AT AROUND
1345FT AND IS STARTING TO OVERTOP AND GO OVER THE SPILLWAY. IN
THE PAST, IT HAS TAKEN UP TO 6 DAYS FOR A RELEASE AND MAIN
FLOODING EVENT TO START AFTER THE BASIN IS FULL. WE WILL
CONTINUE TO MONITOR CONDITIONS IN THE BASIN AS WELL AS THE
MENDENHALL RIVER AND WILL MAKES UPDATES AS THEY ARE NEEDED.
VISIT WEATHER.GOV/AJK/SUICIDEBASIN FOR MORE INFORMATION.
FIRE WEATHER...
HIGH PRESSURE CONTINUES TO SIT OVER THE AREA WITH NO REAL SIGNAL
OF A PATTERN CHANGE LIKELY UNTIL THE UPCOMING WEEKEND. WITH THE
PERSISTENT WEATHER, WE HAVE STARTED TO SEE TEMPERATURES RISE INTO
THE 70S WITH SOME POCKETS OF 80S FOR THE INLAND AREAS WITH WARM
TEMPERATURES EXPECTED TO CONTINUE THROUGH THE WEEK. LOOKING AT THE
PAST FEW DAYS, RELATIVE HUMIDITIES HAVE FALLEN DOWN TO THE 30S TO
40S FOR SOME AREAS DURING THE DAYTIME HOURS WITH REBOUNDING
DURING THE OVERNIGHT HOURS INTO THE 90S. WITH THE CONTINUED LACK
OF RAIN, FINE FUELS SUCH AS GRASSES WILL CONTINUE TO DRY. ISOLATED
THUNDERSTORMS ARE ONCE AGAIN POSSIBLE THIS AFTERNOON ACROSS THE
FAR NORTHERN PANHANDLE BORDER OF CANADA.
OVERALL, EXPECTING THE DRY AND WARM CONDITIONS TO CONTINUE
THROUGH THE WEEK WITH FIRE WEATHER CONDITIONS CONTINUING TO
DEVELOP, THE MAIN VARIABLE TO WATCH FOR WILL BE DAYTIME WINDS. AS
OF NOW, EXPECTING THE WORST FIRE WEATHER CONDITIONS TO BE
THURSDAY AND FRIDAY AFTERNOON, HOWEVER GIVEN THE PERSISTENT
PATTERN CAN'T RULE OUT THIS EXTENDING FURTHER INTO THE WEEKEND.
AJK WATCHES/WARNINGS/ADVISORIES
PUBLIC...NONE.
MARINE...NONE.
SHORT TERM...CONTINO
LONG TERM...AP
AVIATION...DS
MARINE...NM
HYDROLOGY...NM
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