textproduct: Juneau

SYNOPSIS

Key Messages:

- An unseasonably strong system impacts the southern half of the panhandle through Sunday night. With bands of rain and gale force winds in Dixon Entrance, and breezy conditions for southern Prince of Wales and Annette Islands.

- Conditions improve Monday as the system departs, with clearing skies and warm daytime temperatures taking hold. Monday looks to be the nicest day of the week with daytimes temperatures reaching the mid to high 60s.

- Another front arrives into the N Panhandle by Tuesday afternoon into mid week, bringing another round of rain and wind to communities along the coast and along and north of the Icy Strait Corridor through Tuesday night.

LONG TERM

/Tuesday night through Friday/ A weak warm front is expected to move over the panhandle from north to south, beginning Tuesday evening. This front is preceding its parent low, which is currently tracking along the Aleutians and into Bristol Bay. Guidance now suggests the low is moving slower than initially thought and will likely not cross into the Gulf of Alaska until late Wednesday night into Thursday morning. When it does arrive, it is expected to dissipate as it reaches the central Gulf due to weaker upper-level support. The movement of this low will be associated with significant southwesterly fetch and longer wave periods in our outer marine zones. Refer to the marine discussion for more information.

The front's primary impacts will be felt across the northern panhandle, bringing moderate rain showers on Wednesday. This is attributed to proper instability accompanying the frontal passage, decent low-level lapse rates, and moisture advection into the inland areas. 24-hour precipitation totals from Tuesday evening into Wednesday evening are expected to be highest inland, along the windward side of the Coast Range, and along the northeast Gulf coast. There is high confidence (80%) in total precipitation ranging from 0.65 to 1.0 inches across these areas, while other parts of the panhandle are forecasted to see 0.45 inches or less. Windier conditions are anticipated in Lynn Canal, Taiya Inlet, and Stephens Passage. Sustained winds of 20 to 25 knots are forecast to peak Tuesday night and Wednesday as the front moves through. Frederick Sound is less likely to experience a significant increase in winds due to the general north-south orientation of the pressure gradient and weak ridging over the southern panhandle and Haida Gwaii region.

Later in the week, ridging is expected to build over a greater portion of the panhandle, following the front and the dissipation of the Gulf low. This transition will lead to more zonally oriented onshore flow and relatively benign light rain. While minor warming is anticipated to begin mid week into the weekend, temperatures will still remain seasonably cooler.

AVIATION

/through 00z Tuesday/ Predominate VFR flight conditions ongoing this afternoon with SKC to FEW deck along and north of the Icy Strait Corridor terminals in contrast to increasing cloud cover and rain moving into the southern panhandle ahead of an approaching front. Expecting 2 separate regimes moving into the evening with flight conditions degrading to upper end MVFR to VFR across the S Panhandle terminals as aforementioned low moves south of Haida Gwaii, extending an occluding front northward into the S panhandle. For the northern panhandle TAF sites, along and north of a line from Sitka to Juneau, VFR conditions will continue with a FEW to SCT mid lvl deck and winds around 10kts and gusts up to 20kts.

Main aviation impact will for the S Panhandle, along and south of Petersburg to Kake with slight visby drops within heavier showers and light to moderate E-ly LLWS for PAKW, PAKT through 09z this evening being the primary threats. Forecast winds for S Panhandle terminal sustained winds 15 to 25kts with gusts up to 30kts, potential for higher sporadic 35 kt gusts near Metlakatla, Ketchikan, and Hydaburg.

Widespread aviation conditions increase through Monday afternoon with clearing skies from N to S and VFR flight conditions prevailing into the early afternoon as low departs south of the area and surface ridging moves in. Monday will likely be the best conditions for aviation through the week.

MARINE

Outside: A 980mb low located 200 miles SW of Haida Gwaii continues to track E across the N Pacific this afternoon, and is forecast to track just S of Haida Gwaii tonight into early Monday morning. The associated gale force front with this system will stall over the SEAK panhandle through this evening as it occludes, keeping a predominate SE to E-ly wind regime across the S panhandle inner channels and coastal waters through the evening before eventually turning more N-ly overnight into Monday as low tracks south away from the area and off-shore conditions develop. Marine interests along coastal PoW and S Clarence should remain aware, buoys across central Gulf and near Dixon Entrance are reporting sustained winds 30 to 35 kts with gusts up to 45kts. Mariners should continue to take caution along the S Panhandle coast with Gale Warnings issued through this evening. For Monday, winds become NW along the coast between 15 to 25kts with wave heights 8 to 11 kts as low continues to track SE away from the area.

Inside: A strong front continues to push into the S Panhandle inner channels through Sunday night as a low moves towards Haida Gwaii, with reported sustained winds around 20kts and gusts up to 30 kts S of Gravina Island. As this low moves south of the Panhandle through tonight, anticipate northerly winds to build through the S inner channels along and south of Frederick Sound, likely reaching moderate to fresh breezes, especially in Chatham and Sumner. Overall inner channel winds diminish overnight into Monday morning as the low tracks south with surface high pressure moving eastward over the area. With clearing skies, anticipating typical afternoon sea breezes to develop around 10 to 15kts,with stronger winds around 20kts expected in Lynn Canal.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...Gale Warning for PKZ641-661-662. Small Craft Advisory for PKZ012-035-036-053-642>644-651-652-663- 664-671-672.