Area Forecast Discussion
Issued by NWS Juneau, AK
Issued by NWS Juneau, AK
462 FXAK67 PAJK 071256 AFDAJK Southeast Alaska Forecast Discussion National Weather Service Juneau AK 456 AM AKDT Sun Jul 7 2024 .SHORT TERM.../Through Sunday night/ Rather quiet short range period today. The advance and retreat of the low marine layer clouds and how they effect local weather are the main concerns over the next 24 hours. Currently, most of the Gulf and the northern inner channels are under that layer of clouds though ceilings rise as you get farther from the outer coast (Juneau, Skagway, Haines, and Angoon have ceiling around 3500 ft or higher). For today, the marine layer clouds are expected to retreat with only the western part of Icy Strait and the outer coast north of Point Ommaney still seeing mostly cloudy skies by afternoon. Areas that clear out will likely have temperatures reach into the upper 60s or low 70s as a result. Cloudy areas will mainly be in the 60s for highs. The clouds are expected to invade again tonight with most of the northern inner channels and outer coast seeing cloud cover again. Some uncertainly on how far the clouds retreat and advance over the next 24 hours which could affect observed temperatures. Winds are expected to remain mostly low. Highest winds are in the gulf with NW 20 kt across the southern near shore waters through the period. Strongest winds in the inner channels will mainly be from afternoon sea breeze circulations when they do form. .LONG TERM...Overview: High pressure ridge over the AK Gulf remains in place into the weekend keeping overall quiet weather. An active pattern returns mid week. On Monday, the ridge will remain strong with anticyclonic flow aloft. The result is a clearing of skies throughout the panhandle with temperatures in many areas hitting above 70 degrees. Naturally, typical sea breezes will develop, and areas around Point Couverden, Cross Sound, and Northern Lynn Canal will increase wind speeds in the afternoon. Otherwise, enjoy the calmer weather before clouds and potentially rainy and windy pattern sets in mid week. Wednesday begins an active pattern for the panhandle with the entrenched ridge slowly being broken down on Tuesday. Model consistency on this particular front has not been ideal, but what can be said is that winds will generally increase to at least 15-20 knots in the inner channels with the fronts passage. Towards the north, troughing in the Yukon and northern British Columbia will lead to dropping surface pressure. With the rising pressure in the post frontal environment, it will result in a tightening gradient in northern Lynn Canal and Taiya Inlet. Currently, gusts to 40 mph near Skagway are expected, but changes in placement of the troughing could lower or raise wind speeds. Beyond the mid week, ensemble means were largely used to make generalizations about the upper air pattern. Ensemble spread was too large with individual shortwaves moving along an active, trough pattern. Ultimately, what can be said is the pattern will remain active, but individual features cannot be determined at this time. && .AVIATION... Mixed bag IFR to VFR flight conditions this morning across the panhandle under a gradient of OVC to SKC skies. Main aviation concern for today remains PAYA with persistent MVFR to IFR conditions, isolated drizzle, and CIGS AoB 2000ft through the period. Outside of Yakutat, anticipating improving weather and predominate VFR flight conditions to prevail across the majority of the area after 18-20z with CIGS AoA 5000ft. Winds should remain around 10kts or less through today for majority of the panhandle, except for PAGY, which could see sustained winds up to 15kts and isolated gusts up 30kts. && .AJK WATCHES/WARNINGS/ADVISORIES... PUBLIC...None. MARINE...Small Craft Advisory for PKZ644. && $$ SHORT TERM...EAL LONG TERM....NC AVIATION...NM Visit us at http://www.weather.gov/Juneau