textproduct: Juneau

UPDATE

Updated the Aviation Section to include the 18z set of TAFs.

PREV DISCUSSION......ISSUED AT 553 AM AKDT Mon Aug 10 2026

SYNOPSIS...

Key Messages:

-Suicide Basin glacier dammed lake continues to fill. At this time, it is expected to be full sometime August 11th or 12th. In the past, it has taken up to 6 days for the main flooding event to start after the basin is full. Visit weather.gov/ajk/suicidebasin for more information.

-No significant rain chances or rainfall amounts with a gradual warming trend expected through the week for the panhandle.

SHORT TERM.../Today through Tuesday night/ Continued quieter weather lasts into today, with a warming and drying trend continuing through mid to late week. Lingering showers are possible Monday into Tuesday as convective activity lasts to the north and east in British Columbia and the southern Yukon, with the upper parts of the Haines Highway and near White Pass both seeing higher potential for seeing showers move in. There is also a chance of some isolated thunderstorms moving into the northern panhandle close to these areas today, with the highest chances being during the afternoon hours, however the question on if these thunderstorms will actually push into our area remains uncertain. Some showers may push across into other inland parts of the panhandle from the east, however much of the convective activity is expected to dissipate as they move over the ice fields.

A stronger ridge of high pressure will set up Tuesday into Wednesday over the Gulf, allowing for a shift from a W-ly flow to more of a NW- ly and offshore flow, keeping some potential for a low stratus marine deck sitting offshore and lowered visibility overnight into the morning for some communities and waters along the Gulf coast. The offshore flow will help begin to clear out the cloud cover over the panhandle, and along with elevated 850 mb temperatures will allow for warmer temperatures through the week. Monday and Tuesday will still see some lingering cloud cover over primarily the central and northern panhandle, before clearing up into Wednesday across more of the panhandle. Temperatures will go from highs in the low 60s to low 70s today to reaching mid 70s to near 80 by Wednesday. Sea breeze potential of 15-20 kt in the afternoon and evening for areas that clear up during the day.

LONG TERM.../Wednesday through Saturday/ Wednesday, a closed low south of the Aleutian chain will reach full maturity, beginning to decay as it lifts north. Three primary features of interest as this system moves into the Gulf are: strength of the accompanying surface low, clear/warm over the Panhandle for the mid to end of the week, and moisture transport into the region by the weekend. Touching on the low first, ensembles show agreement that this system will make landfall along the AK Peninsula, with southerlies building in the central Gulf; winds remain below gale force. Our stubborn high over the eastern Gulf cedes territory, making a slight retreat into the Panhandle, with north-westerlies still impacting much of the coastal waters. Overall, little concern for major marine impacts with continued focus for northwest winds of moderate to fresh breezes along the Alexander Archipelago and sea breezes thru the inside.

As this high shifts into the Panhandle Thursday, warm and dry once again becomes the theme. Digging into the 850mb temps, the LREF shows a left-skewed distribution based around 7C to 15C, with the mode around 13C, translating to 75F to 85F surface temps, about 10F above normal for this time of year. The Extreme Forecast Index shines more light into this, with agreement in abnormal warmth increasing its footprint over the Panhandle into the end of this week. A note, its not just about the afternoon high temperatures, nightly low temperatures also likely remain about 10F above normal for most of the region.

Moving onto moisture, by the end of the weekend this pattern will begin to break down the dominant high, or at a minimum, push the ridge further east, with southwesterlies picking up on some equatorial moisture and funneling it into the Gulf. A few ensemble outliers want to bring a quick hit of moderate AR conditions; however, overall modest Integrated Vapor Transport values suggest just an increase in clouds, and perhaps some light rain, by the end of the weekend.

AVIATION.../through 18z Tuesday/...VFR to MVFR conditions for most of the panhandle with some pockets of IFR conditions being reported. Conditions are expected to improve this morning as we see offshore flow and daytime heating increase. With the clearing conditions, sea breezes should kick in later this morning and afternoon. Heading into this evening, the marine layer looks to return to the area bringing MVFR conditions and potentially IFR conditions. There is moderate confidence in these conditions for the overnight hours with improvement to VFR expected again tomorrow morning.

MARINE...

Outside: A 1023mb high pressure remains stationary over the central Gulf into early next week, keeping generally overcast skies with light and variable winds along in the outer waters. Wave heights remain largely benign through the early week, around 4ft or less 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 down to Dixon Entrance around 10 to 15 kts or less, with the strongest winds expected in the vicinity of Cape Spencer and Cape Decision, particularly by the afternoon hours. 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. High pressure expands across the rest of the Gulf and panhandle and continues through the end of the week.

Inside: Conditions across the inside waters remain relatively benign this morning with only a few areas seeing winds above 10 kt, namely near ocean entrances near Cross Sound and into Icy Strait. 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. This pattern of relatively benign conditions with marine layer influence and patchy fog in the morning giving way to increasing winds and sea breezes by the afternoon will hold true through at least midweek. Wave heights remain 4 feet or less through early week as well with no significant systems to break down the influence of high pressure out in the gulf.

HYDROLOGY... Suicide basin continues to fill this Monday morning with no major changes overnight, rising to around 1343 ft as of 4am AKDT. The overall message remains the same, with the cloudy and cool weather in combination with the calving event over the weekend, the most likely date for a full basin is August 11th to 12th. The overflow channel remains around 1350ft. In the past, it has taken up to 6 days for the main flooding event to start after the basin is full and started to overtop into the overflow channel.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...None.