textproduct: Juneau

UPDATE...Update to include 6Z TAF Issuance

SYNOPSIS

Key Messages:

- Decent break in weather for much of the region through the week.

- Main threat to mariners and aviators is periods of dense fog, most likely in the morning and evening hours.

LONG TERM

Continued little change for the long term, with quiet weather and above normal temperatures for most of the upcoming week. A strengthening mid/upper level ridge stretching from the interior of the state down through SE AK will divert would-be weather makers well away from the panhandle. As the ridge retrogrades into an omega block like feature to the west, building high pressure in the Yukon will increase northerly winds. Until these winds pick up, low level stratus and fog will continue to be a hindrance to mariners and air travel through a good portion. Warm 850 mb temperatures, which is helping hold this ridge in place, look to be slowly eroded away by the cooling temperatures in the Yukon area pushing southward. Forecast pattern still no track for a return to highs in the mid 20s to low 30s for most areas by the end of the week.

AVIATION

Dense fog continues across the much of the interior panhandle, keeping a majority of TAF sites at LIFR. Yakutat has had a few instances where a low layer tried to develop this afternoon, but they are still holding strong at VFR. A marine layer keeps attempting to push inland, which would limit fog potential but lower ceilings. Currently thinking the light offshore flow will hold this back, though a light low cloud layer may develop through the early morning hours if winds weaken enough. Haines and Skagway are expected to remain clear through the period, with outflow winds picking up midday. Sitka also is expected to remain clear through the period. The southern panhandle managed to stay clear for most of the night, but conditions are now beginning to deteriorate as a low layer of fog tries to move in and bring down visibility. This fog is forecast to only be patchy and light, so not as dense as the rest of the panhandle.

The dense fog for much of the panhandle is expected to persist into Monday morning, continuing LIFR conditions. Some locations have dropped enough below freezing that conditions may temporarily improve, but are expected to drop back down through the early morning. Outflow winds will steadily increase through the day, with gusts up to 30 kts out in Skagway and Haines. The increasing winds are expected to start from north to south, which will allow for the fog to mix out and improve conditions.

MARINE

Inside (Inner Channels): Lighter winds with low seas continue across most areas of the inner channels through the first half of Monday, before weak outflow winds begin across Northern Lynn Canal, potentially reaching upwards of strong breeze for areas N of the Icy Strait Corridor. Outflow winds continue to linger through the remainder of the week, potentially strengthening as we approach the weekend.

Outside (Gulf and Coastal Waters): Relatively quiet marine conditions in the gulf with mainly southeast to easterly winds around 10 to 15 kts. Significant sea heights remain around 8 to 10 ft. The strongest winds and highest seas remain around the northern gulf. Both winds and seas will decrease tonight through Sunday. These more benign conditions last well into next week.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Dense Fog Advisory until noon AKST Monday for AKZ320-321- 324>327- 329. MARINE...None.