textproduct: Juneau

SYNOPSIS

Key Messages:

- Warmer temperatures continue Sunday, though slightly cooler as marine layer encroaches further into the outer coast and Cross Sound/Icy Strait.

- A low returns to the gulf bringing cloud cover and rain chances back to SE AK Monday.

LONG TERM.../Tuesday through Friday/

Generally cloudier and showery conditions last through mid to late week. The developed low in the western Gulf centered south of Kodiak Island will begin to gradually push eastward, weakening as it moves into the central Gulf. This low will send another front across the northern half of the panhandle on Tuesday, with ridging over the eastern Gulf and southern panhandle keeping any precipitation directed northward. Showers will continue behind this into Wednesday as the weak shortwaves rotate around the upper level low over the Gulf, enabling the onshore flow and showers to continue even as the surface low weakens in the central Gulf. Uncertainty remains on the strength and placement of the shortwaves moving through on Tuesday and Wednesday, but high confidence on it staying across the northern panhandle and bringing lighter amounts of precipitation (accumulations of up to 0.15 inches in 24 hours for the NE Gulf Coast and Icy Strait Corridor).

The potential for more widespread precipitation returns by Thursday morning as a stronger low develops in the north Pacific, though the lack of model agreement on the location and strength of this feature is making it uncertain at this time as to how much of the panhandle will be impacted. At this time the GFS seems to favor a stronger low developing and moving northeastward towards Haida Gwaii into the eastern Gulf, with the associated front moving across the southern and central panhandle. The EC and Canadian appear to favor an upper level low digging more into the Pacific and keeping this low further southward, rather than moving into our coastline, and likewise limiting how far northward the precipitation impacts will be and the amount of rainfall expected Thursday into Friday. The clusters remain rather split between the two solutions, with the favored solution for the forecast being in between, with the low staying near Haida Gwaii and southward rather than into the panhandle or bypassing it entirely like the Canadian suggests.

AVIATION

The marine layer has slowly moved further eastward over night bringing the low stratus deck as far east as Gustavus and Ketchikan. This marine layer has quickly reduced ceilings to below 1000 ft over these areas, and along the gulf coast including Klawock, Yakutat, and Sitka. There has also been periods of visibilities as low as 2 SM. Similar to yesterday this marine layer will slowly retreat during the day allowing for mostly VFR conditions across SE AK. The marine layer is then once again anticipated to move into the inner channels again Sunday night into Monday as the ridge remains over the eastern gulf. This will once again lower flying conditions for the aforementioned locations. Although the ridge remains over the far eastern gulf, an area of low pressure has begun to move eastward. We will start to see more cloud cover and light rain, as early as Monday morning, due to this low.

MARINE

Inside (Inner Channels): Winds across the inner channels remain around 5 to 15 kts with the strongest winds (20 to 25 kts) once again over Icy Strait, Point Couverden, and Young Bay overnight. Even these locations have seen wind speeds decrease this morning as the ridge continues to move eastward and weaken. Areas that have saw those stronger winds over night, mainly west to east oriented channels, will once again see an increase in winds this evening, but they are not anticipated to be as strong as previous nights. Behind those stronger winds, an overall decreasing trend will occur Monday. This is due to the ridge weakening and moving out of the area. An exception to this is Taiya inlet where increased southerly winds to near 20 kts are anticipated Monday afternoon and evening. Otherwise, a marine layer remains over the eastern gulf pushing into portions of the inner channels. This marine layer has created areas of reduced visibilities as low as 2 NM into Clarence Strait, Cross Sound, and Icy Strait. This marine layer will retreat throughout the day before returning once again tonight.

Outside (Gulf and Coastal Waters): A ridge remains over the gulf bringing northwesterly winds of 15 to 20 kts over the eastern gulf. These winds are anticipated to decrease throughout the day as the ridge weakens and begins to move out of the area. This ridge has also allowed for a marine layer to develop and remain over the eastern gulf. The main impact from this marine layer is areas of lowered visibilities. A pattern change is in store as an area of low pressure will the replace the ridge Monday. This will make winds across the gulf become southeasterly. As this low moves into the area, strongest winds will be over far offshore waters. Even then strongest winds are expected to be around 15 kts. These lighter winds of 10 to 15 kts are expected to continue into mid week.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Heat Advisory until 8 PM AKDT this evening for AKZ319-328- 330>332. MARINE...Small Craft Advisory for PKZ021-641-642-661.