textproduct: Juneau

SYNOPSIS

Key Messages:

- Periods of rain return to the northern and central panhandle as a low lingers in the Gulf of Alaska, sending a series of weak fronts inland through mid-week.

- Drier conditions are expected to continue for the S Panhandle communities through at least Tuesday. Rain chances increase through Thursday as a stronger system moves out of the N Pacific towards Haida Gwaii.

LONG TERM.../Thursday through Monday/

A stronger low will develop in the north Pacific during the week, moving into the eastern Gulf towards Haida Gwaii by Wednesday night. This system will bring more widespread rainfall across the panhandle starting with the southern panhandle and south/central outer coastline late Wednesday night, before moving eastward through the day Thursday. There is higher confidence on this system bringing rainfall the southern panhandle up to Icy Strait Corridor, with less confidence on extending into the far northern panhandle from Yakutat over to Skagway and Haines. It will move onshore just around Haida Gwaii into BC by Friday, but there is potential for a meso low connected to this main system that may move in closer to the panhandle rather than stay just southward. The strength and location of this feature may result in rainfall pushing further northward into Skagway and Haines. Overall the precipitation will be heaviest across the southern coastline, with between 0.5 and 1.0 inches expected from Sitka along the coast down to PoW and 1 to 1.5 inches expected for Ketchikan / Annette Island.

Behind the low pressure system Friday, on shore flow is expected to develop with a ridge of high pressure. While on shore will keep showers in the forecast, the overall rain chances will be lower for the Alaska Panhandle.

As the ridge builds Saturday, some stronger winds are possible from the eastern Gulf Coast toward Haida Gwaii and Dixon Entrance. In the inner channels, winds look fairly benign, other than some sea breeze formations Saturday, but that will depend on skies clearing which seems unlikely at this time with showers around.

By early next week, another low pressure system looks to form in the Gulf of Alaska and potentially increase shower chances. However, there is model disagreement on this exact timing and placement of the low pressure system early next week, so confidence is low in this system.

AVIATION

Variable flight conditions are occurring across the panhandle as a low pressure system is bringing clouds and rain showers to the central to northern panhandle. Then under some of the higher clouds, there is still a lower stratus deck along the eastern coast. This stratus deck is once again allowing for IFR conditions over Yakutat, Sitka, and Klawock this morning, with ceilings below 1000 ft. Those locations are likely to see an improving trend over the next couple of hours. A few other areas in central to northern SE AK are still seeing MVFR conditions this morning. Similarly to the coast, these areas are very likely to see improving ceilings, becoming VFR by late this morning. By this afternoon, widespread VFR ceilings and visibilities are anticipated across SE AK. Winds remain fairly benign through the taf period. Strongest winds will be near Skagway this afternoon when southerly winds once again increase to around 10 to 15 kts.

MARINE

Inside (Inner Channels): An overall decreasing trend will continue throughout the inner channels today. Strongest winds are occurring, and expected to continue through the morning, over N Lynn Canal into Taiya Inlet. This area is seeing southerly winds around 15 to 20 kts. These winds are anticipated to decrease late this afternoon. There is a chance that winds over N Lynn Canal increase once again tomorrow morning, but it is likely that they will not be as strong. Through the middle of the week, 1 to 2 ft wave heights are prevail through the inner channels, with significant seas around 3 to 5 ft at ocean entrances. Looking ahead, an area of low pressure develops in the northern Pacific Wednesday. This low will then move eastward toward Haida Gwaii increasing winds over S Clarence Strait. Winds currently look to be around 15 to 20 kts over S Clarence, but we could see lighter, or stronger winds, depending on the final track of the low pressure system.

Outside (Gulf and Coastal Waters): Southeasterly winds continue across the gulf as an area of low pressure remains over the western gulf. Because of this, wind remain fairly benign Tuesday into Wednesday. Strongest gulf winds remain just south of Clarence strait around 15 to 20 kts. Overall significant wave heights around 4 ft persist along the coast for Tuesday. On Wednesday, southerly gulf winds will become northerly as a more organized low tracks across the northern Pacific towards Haida Gwaii. We will continue to see northerly winds persist into Thursday. At this time, we will also see building wave heights across the southern gulf, reaching 5 to 7 ft by Thursday night.

HYDROLOGY

Snow melt and a string of above normal temperature days across the Chilkat Valley have resulted in elevated stream flow in rivers and streams across the area. While temperatures will cool somewhat through the week, snow levels in excess of 5000 feet will continue to support these elevated stream flows through the time frame.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...None.