textproduct: Juneau

SYNOPSIS

Key Messages:

-Another front arrives late Friday night into Saturday, primarily impacting the northern half of SE AK

-Waves of light rain continue to move through the NE Gulf Coast through the first half of next week, with periods of drier weather in between

-Drier weather generally expected for the the southern half of the panhandle.

LONG TERM.../Sunday through Tuesday/

Over the second half of the weekend the primary synoptic scale feature driving the weather will continue to be a a prominent ridge aloft over the Gulf into the western seaboard which continues to block systems from moving directly into the Panhandle. Winds will likely remain elevated in Glacier Bay and Lynn Canal given the perpendicular surface pressure gradient. While some breezy conditions impact the north, the Panhandle should start drying out as southerly flow steers moisture west of our region into the end of the weekend.

One note is that Yakutat will remain under wet conditions at times through the weekend.

Monday a negatively tilted trough begins to lift toward the Kenai, steering moisture and elevated seas into the northern coast. Some rain will return next week for the central and northern Panhandle but amounts look to remain well under 1 to 2 inches in a 24 hour period, with the influence of a surface high across the eastern gulf driving more typical early summer weather for the central and southern regions.

Models are continuing to agree on a general warming trend into the next week as another ridge builds over the Gulf. The NBM is keying on seasonably warm temperatures across the southern panhandle early to mid week, with areas on Prince of Wales seeing numbers into the high 60s given a proper clearing of skies and longer duration of solar heating under the ridge. Precipitation may return at the end of next week ahead of another low pressure system.

AVIATION

No major changes to aviation forecast this afternoon. A ridge is currently stalled out across central and southern portions of the Alaska panhandle this afternoon. Across the northern panhandle, high forecast confidence continues of VFR flight conditions into the early evening with CIGS AoA 5000ft. Conditions will gradually deteriorate through this evening as a low pressure system and its associated front will arrive through early Saturday morning. This system will bring rain chances across northern TAF locations, with MVFR flight conditions to with low to medium forecast confidence of IFR ceilings and visibilities through Saturday morning. As the front moves north through Saturday morning, anticipating winds to increase across the N Panhandle TAF sites with sustained winds 15 to 25 kts with gusts up to 35kts possible across Yakutat, Haines, and Skagway. As the front pushes inland, brief period of southeasterly low-level wind shear expected around 35kts 09z to 13z for Yakutat.

MARINE

Outside (Gulf and Coastal waters):This beautiful Alaska Friday, satellite derived wind passes show two regimes across the Gulf and our coast: the first being northwesterly gentle to moderate breezes along much of Sitka/PoW coast, in thanks to transiting surface high. The second is stout southerly flow across the central Gulf from a gale force low sliding north, bringing easterly winds along Cape St. Elias. Sea state is currently being dominated by southwesterly swell, 10 to 11 seconds near 4 ft, with significant heights of 5 ft. The exception is the northern coast where we are seeing building easterly seas from increasing winds.

Moving through Friday evening winds will continue to increase to gale force along Cape St. Elias, with northwesterly winds becoming southerly along the rest of our coast. Anticipate gale force conditions to remain near Cape St. Elias, southeasterly near-gales to strong breezes from Yakutat to the Fairweather Grounds, and southerly fresh breezes to moderate breezes from Cape Edgecumbe south to Dixon.

Touching on sea state, a variety of wave systems will be present in the Gulf Friday into Saturday. Looking at the northern coast first, building seas from the south, with dominant period less than 10 seconds; however, westerly swell will also be present, with a period of 14 to 16 seconds and significant wave heights near 7 to 9 ft. For Baranof and PoW coast, expect the primary wave system to be the prominent westerly swell mentioned above. Moving through Saturday into Sunday southwesterly swell continues to dominate the coast, likely near 8 ft.

Inside (Inner Channels): Primary threat across the inside Friday evening into Saturday morning will be a frontal passage across the north, bringing southerly fresh to strong breezes to much of Glacier Bay and Lynn Canal. For folks planning on operating in the northern portion of Glacier Bay, caution advised, especially near Reid Inlet and other areas exposed to southerly winds.

For the remainder of Saturday and into Sunday most of the Inner Channels will be seeing winds of gentle to moderate breezes. The exception will be Lynn Canal, and perhaps Glacier Bay, where will continue to see southerly winds of fresh to perhaps strong breezes associated with sea breezes. For the central and southern Panhandle we are likely to see northerly winds, with moderate to fresh breezes impacting far southern Clarence Strait.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Wind Advisory from 7 AM to 1 PM AKDT Saturday for AKZ318. MARINE...Gale Warning for PKZ651-652-671-672. Small Craft Advisory for PKZ012-022-053-641>644-661>664.