textproduct: Juneau

UPDATE

/18Z TAF Issuance/ Not much has changed for the 18Z TAFs with VFR conditions still across the panhandle. Low ceilings prevail through the morning with coastal regions expected to remain at or around 3000 ft until tonight when they will drop into MVFR. Interior panhandle areas will remain at VFR as the low clouds should remain closer to the outer coast. No precipitation or drops in visibility are expected.

LONG TERM.../Saturday through Wednesday/

A broad upper level ridge and surface high pressure system in the southern Gulf of Alaska continues to build through the week, very slowly moving northwest. This ridging will funnel more dry air over the panhandle, continuing the warming and drying trend into the long term. Multiple approaching shortwaves in the gulf attempt to strengthen through the weekend which could increase chances for light precipitation along the northern gulf coast, though all seem to break apart before reaching the outer coast. The surface ridging continues to strengthen into early next week which will clear out skies and tighten the pressure gradient, increasing wind speeds along the gulf coast. By Monday afternoon, sustained winds will increase to at least 20 kts going into cross sound, with highest speeds reaching around 25 kts off the southwestern coast of PoW. Gusts may reach 30 kts in Dixon Entrance. Clearing skies will allow for a sea breeze to develop in some of the inner channels, with winds potentially reaching 10 to 15 kts near the water in Juneau, Haines, and Skagway. Stronger winds are expected through Icy Strait and up Lynn Canal with this sea breeze, peaking in the mid afternoon. This is also conducive to marine layer development along the gulf coast which will bring low clouds to coastal regions and pushing into Cross Sound.

High temperatures of up to 15 degrees C at 850 mb and clearing skies indicate warmer surface temperatures for early next week, peaking Monday and Tuesday. Interior regions of the panhandle will experience the highest temperatures, with highs potentially reaching the mid to high 70s and lows in the mid 50s. Max temp EFI values have increased to 1 Monday through Wednesday, with NBM probabilities currently indicating a 60% potential of reaching 80 degrees in areas of Skagway and Haines on Tuesday.

AVIATION

Variable flight conditions continue across the panhandle as a surface ridge moves into the panhandle. An upper level trough continues to allow for cloud cover, mainly across the northern panhandle and areas near the gulf coast. In those areas, ceilings remain near MVFR at or below 2500 ft. An exception to this is a lower cloud deck with ceilings below 1000 ft that has formed over Klawock. These lowest clouds are expected to increase to mainly VFR ceilings this morning into this afternoon, with overcast skies of 4000 to 6000 ft remaining along the gulf coast. An upper level trough is then expected to move over the panhandle this evening. This will again create MVFR ceilings along the coast for the overnight hours Friday night.

Winds remain below or near 10 kts, for land areas, throughout the day. Skagway will once again be an outlier with winds increasing to 15 kts, with gusts up to 20 kts, in the afternoon to evening hours. There are no LLWS concerns through the TAF period.

MARINE

Outside: Winds along the coast stay NW 15 to 20 kts through Friday as ridging rebuilds. The strongest of these winds will be near Cape Decision and into Dixon Entrance. Wave heights remain 5 to 6 ft west of POW Island through the early morning hours, before subsiding to 4 to 5 ft through the afternoon. Winds in the Gulf will stay at these lower speeds until Sunday, where winds along the outer coast will again increase to around 20 kt with seas of 7 to 8 ft just west of POW as the ridge strengthens in the Gulf and the pressure gradient increases. Wave period will be 14 to 16 seconds with a swell from the SW at 3 ft going into Saturday.

Inside: Winds remain on the lower side for Friday into the weekend, with most of the inner channels seeing speeds between 5 and 10 kts. The exception to this is parts of northern Lynn Canal, Icy Strait and southern Clarence Strait, which may see some increases to 15 kts due to the E-W gradient (and N-S gradient for northern Lynn Canal) tightening in the afternoons as well as potential for sea breezes that may cause local increases between 15 and 20 kts.

AJK WATCHES/WARNINGS/ADVISORIES

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