textproduct: Juneau

UPDATE

Updated the Aviation Section to include the 06z set of TAFs.

PREV DISCUSSION......ISSUED AT 335 PM AKDT Fri Jun 19 2026

SYNOPSIS...

Key Messages:

- Mostly sunny skies with warm conditions will remain in place through the rest of the weekend. With cooler temperatures along the immediate coast lines due to onshore flow/sea breezes.

- Conditions will be warmer Saturday with highs in the low 80s away from the immediate coast for southern portions of SE AK. Elsewhere highs are expected to be in the upper 60s to mid 70s.

- A slight chance of isolated thunderstorms for areas east of the Ketchikan-Wrangell line remains for Saturday afternoon.

SHORT TERM.../through Sunday night/...As of Friday afternoon, a weakening upper level circulation continues to depart the region and move southeastward over British Columbia, with only a few showers clipping the southeast panhandle near Hyder. However, offshore northeasterly flow aloft from the Yukon Territory and British Columbia are propagating showers towards the border, with thunderstorms being observed via satellite. While none have made it across the border as of this discussion, a low chance remains possible through the early evening hours for this to occur before daytime heating wanes and lapse rates diminish overnight. The strength of the ridge currently over the Gulf of Alaska is also playing a part in suppressing cloud development over much of Southeast Alaska today, with many areas reaching the upper 60s and some even low to mid 70s, especially away from the coast where sea breezes have begun to develop. This is also working to deter thunderstorms from pushing into the panhandle; time will tell if they break through.

This warming trend is expected to continue Saturday, with a heat advisory being issued for a majority of the southern panhandle, including Hyder in the southern interior, as well as Haines (primarily out the road). Temperatures are expected in those areas to reach the upper 70s and potentially low 80s, particularly inland away from sea breeze influences. Synoptic flow and the continuing hot temperatures over the interior will shift the isolated thunderstorm potential southward to the eastern portion of Misty Fjords and over to Hyder on Saturday, with timing again being limited to the late morning and through the afternoon hours.

At the surface, the advancing surface ridge combined with daytime heating has begun to break up the marine layer in the southeastern Gulf of Alaska similar to Thursday. Unfortunately the northern gulf coast will likely see a resurgence of this marine layer once more, though it is not expected to be quite as low. By Sunday, as the ridge axis continues drifting eastward, the marine layer has a higher chance of impacting the outer coast, particularly in the morning hours, as well as briefly pushing into Cross Sound and Icy Strait. Coming up on the summer solstice however, it should once again be pushed back fairly quickly with daytime heating and turbulent mixing by late morning. Overall should be a relatively dry and warm to hot end to the holiday weekend across SE AK.

LONG TERM.../Monday through Friday/...The forecast for next week remains consistent, featuring persistent ridging while we monitor a disturbance in the Gulf that could bring precipitation to the region. Guidance indicates a strengthening upper-level low forming over the Gulf and tracking eastward across Southeast Alaska. A weak mid-level low developing between Monday and Tuesday will assist precipitation formation in the northern panhandle, while a ridge maintains its hold over the southern region.

While upper-level forcing appears to be minimal, a shift to onshore flow Monday afternoon, triggered by a weak low traversing the western Gulf, will likely support orographically driven precipitation over the northern/central panhandle on Tuesday and encroachment of the marine layer further inland overnight and into the morning. This activity will be supported by lingering low-level instability carrying over from the weekend's warm temperatures. Current thinking is that models may be slightly overestimating rainfall accumulations, especially following the recent drier stretch, so backing off on raising QPF amounts at this time. While there is uncertainty regarding the exact placement of the Gulf low, precipitation will be typical for the season, with high confidence that daily accumulations will remain at or less than 0.10 inches and mainly impact the northeast Gulf coast, near Yakutat.

The southern panhandle is forecast to retain a warmer and drier trend as it remains more centrally positioned under the surface ridge. By Friday, the ridge will likely break down as a weak surface trough moves through, supported by an upper-level trough and jet streak, bringing more organized rain showers back across the entire panhandle.

AVIATION...VFR conditions continue this evening for most of the panhandle with the exception of MVFR conditions along the outer coast. The MVFR conditions are expected to expand to most of the outer coast this evening with ceilings dropping down to around 1,000ft. There is some concern for how close the marine layer could make it towards Gustavus this evening so it was included in the TAf. Elsewhere, mostly clear skies are expected to persist. Some areas of patchy fog might be possible with the clear skies but currently there is no concern for fog around the TAF sites for the 06z set.

MARINE...Inside Waters: A ridge building along the outer coast will steer prevailing flow out of the N for most of the inner channels barring Lynn Canal. Prevailing northerly flow for N/S channels will remain between 5 to 15 kt for most locations through the remainder of the week and into the weekend. The exceptions will be Clarence Strait, which will see 10-20 kt NW winds, and northern Lynn Canal, Taiya Inlet, which at times will see S 15-25 kt winds.

E/W channels will see prevailing westerly winds. Sea breeze influences will strengthen winds during the late afternoon and evening hours around Icy Strait and Point Couverden to 15-20 kt through the weekend, with wind speeds then slowly diminishing during the overnight hours.

The chance of a few isolated thunderstorms can't be ruled out on Saturday for locations east of Ketchikan including Behm Canal and Portland Canal.

Outside Coastal Waters: NW winds prevail through the weekend, as a ridge strengthens over the Gulf. The strongest winds (20-25 kt) remain along the SE Gulf Coast, where waveheights of 6 to 8 ft linger through the weekend. Lower waveheights of 3-6 ft are expected for the northern Gulf during this timeframe. S swell of 1-2 ft for the northern Gulf becoming sharply W or NW as one heads into the eastern Gulf.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Heat Advisory from 10 AM to 8 PM AKDT Saturday for AKZ319-328- 330>332. MARINE...Small Craft Advisory for PKZ021-641-642-661-662.