Area Forecast Discussion

UPDATE

For 06z TAF Issuance. Cooling overnight along with the ridge rotating through the panhandle has lead to some patchy fog development along the inner channels, namely in the vicinity of Sumner Strait and the Wrangell Narrows. Expect this to last into Monday morning before mixing out as a front moves in from the west bringing some light rain and overall lowering conditions for the northern half of the panhandle. Improving conditions to largely VFR expected by Monday afternoon before another shortwave brushes the northern panhandle Monday night.

SHORT TERM

The front that was moving through the southern panhandle this morning continues to weaken and dissipate this afternoon. Behind this front, high pressure continues to move into the area before the next, weak area of low pressure is expected to move across the northern Gulf this evening. This low should bring rain mostly to the NE Gulf coast and northern panhandle before high pressure builds back into the area for Monday evening. Rain amounts for the NE Gulf coast look to be around 0.5-0.75" in 24 hours. With the rain passing through the area as well as high pressure building in, there is the chance that fog develops this evening as well as tomorrow evening. With the warmer temperatures, current thinking is that all the precipitation will stay as rain with the exception of places at elevation which could see some minor snow accumulations such as the Klondike and upper Haines Highway.

LONG TERM

/Wednesday through Saturday/ The ridge over the Gulf of Alaska will move east and build over the panhandle through the day Wednesday and into Thursday. This ridge will be associated with low precipitation totals for most of the area. With the exception being northwest of Cross Sound, where showery conditions will remain in place. A second wave of moisture is expected to reach the northern gulf coast Friday morning. This will bring more persistent precipitation, however impacts will be minimal as there is a 20-30% chance that Yakutat will see more than 0.3 inches of rain.

Impactful winds are not expected through the weekend, but the diurnal cycle could cause breezy conditions in the inner channels. However, when skies are clear and winds lighten, there remains the possibility of isolated fog in the overnight hours, particularly the southern half of the panhandle. Temperatures will gradually increase throughout the week as the ridge moves over the panhandle bringing upwards of 60 degrees in Ketchikan and POW Island. Northern locations will see high 40s and low 50s by the weekend.

AVIATION

/Until 00z Tuesday/ Ceilings took much longer to lift over PAPG than expected, but webcams are showing improvement this afternoon. Clouds also moved in with the next front over PAYA earlier, keeping CIGs down there. Between those trouble spots, there have been large breaks over the inner channels and scud hanging over the mountains. Suspect that the positively tilted ridge of high pressure over the central panhandle tonight will make it easier for the clouds currently in place to stratify and lower. Therefore, have kept or added at least a MVFR deck to most TAF sites overnight into early Monday. Some locations across the southern half of the panhandle could see fog again Monday morning. Exception will be PAGY where southerly winds will remain strong and keep conditions VFR, even with light rain approaching from the west overnight.

The front moving in from the west can be seen on satellite and Middleton Island radar. This front will weaken as it pushes into the ridge of high pressure, however still expect light rain for PAYA this evening with conditions slowly lowering. Rain will slowly move over the northern TAF sites overnight.

Sea breeze winds have been trending up as expected for most places. These will drop back off around sunset, then start to back with the approaching front or become light/variable.

MARINE

Outside (Gulf and Coastal Waters): Westerly winds continue to shift as the high pressure moves across the Gulf with the Cape Edgecumbe buoy reporting NW winds at 10 kt while buoy 46085 in the Central Gulf shows a SW wind at 15 kt. A low moving into the Gulf is expected to track across the northern Gulf waters before impacting the NE Gulf coast. 20-25 kt winds are expected for most of the Gulf with the exception of places south of Cape Decision which are expected to remain around 15-20 kt. After this low moves through, high pressure returns to the area before a second, weak low moves through the NE Gulf Monday night into Tuesday. With these lows moving through, waveheights are expected to increase to 8-14 ft, especially for the Central Gulf area. These waves are expected to diminish as we head into Tuesday evening and Wednesday morning as high pressure becomes more firmly in place.

Inside (Inner Channels): Light winds continue for most of the Inner Channels this afternoon with the exception of Cross Sound up through Icy Strait where winds have remained 15-25 kt sustained. These winds are expected to persist through the evening into tomorrow before weakening slightly. For the rest of the Inner channels, winds could get as high as 15 kt with the exception of Clarence Strait which could see winds increase closer to 25 kt with the area of high pressure moving closer to the area. Waveheights for the Inner Channels are expected to remain around 2-5 ft but could be closer to 6-8 ft for the Icy Strait and Lynn Canal regions with the sustained strong winds. High pressure moves in Tuesday night which will lead to NW winds becoming more pronounced, especially for the southern Inner Channels.

AJK WATCHES / WARNINGS / ADVISORIES

PUBLIC...Wind Advisory until 7 AM AKDT Monday for AKZ318. MARINE...Small Craft Advisory for PKZ012-013-021-022-053-641>644-651-652- 661>664-671-672.