textproduct: Juneau

SYNOPSIS

Key Messages:

- A westerly surge of winds is on our doorstep, bringing a shift in winds and relatively cooler temperatures.

- Some clearing is expected on Tuesday, bringing warmer temperatures and drier weather.

- Rain returns to the northern half of the panhandle Wednesday and spreading south by Thursday

- Drier weather looks to lead SE AK into the weekend.

LONG TERM.../Wednesday through Saturday/

Hints of spring will continue to grace the panhandle over the coming week as multiple mid and upper level troughs and ridges bring slightly warmer temperatures interspersed with light to moderate precipitation. A short wave that brought showers to the northern gulf coast beginning Tuesday will be reinforced late Wednesday and bring more widespread precipitation to the panhandle through Thursday and the end of the week. While this is expected to be primarily rain, some snow could mix in in the overnight hours, with highest likelihood north of Icy Strait. However, little to no accumulation at sea level is expected at this time. Some minimal accumulations are possible for higher elevations of the Klondike and Haines Highways. Overall these features are expected to have minimal surface reflections and thus keep seas to at or below 6 ft in the gulf by Thursday. Winds also look to not be that impressive as of this forecast issuance, with some locations potentially reaching strong breeze (22 to 27 kt) at most. Onshore flow with the aforementioned short waves impacting the panhandle will be replaced by offshore and/or parallel flow by the end of the week and into the weekend as another ridge builds into the gulf.

With clearer skies expected to develop over the weekend, modest sea breezes will be on tap for communities along the inner channels. Some weak offshore flow could develop over the northern inner channels briefly Friday night into Saturday as the latest feature exits the region, however this should then be offset by sea breeze development during the day Saturday and overall relaxing of the pressure gradient over the inner channels. Overall it looks to be a relatively quiet and benign pattern ahead for the weekend.

AVIATION

/through 00z Wednesday/ MVFR to VFR flight conditions ongoing this afternoon with some improvement as the low from this morning is currently situated between Prince of Wales Island and Ketchikan. Through the rest of Monday afternoon, any mixed precipitation will turn to rain as daytime heating kicks in. More of a transition period through the evening with aforementioned low departing and a ridge of high pressure over the Gulf gradually moving overhead through Tuesday morning. Not expecting too much improvement in flight conditions in the wake of the low with MVFR dominating through Monday night with brief improvement periods of VFR expected. Widespread precipitation decreases through this evening, becoming more isolated and showery in nature along the coastal terminals as on- shore flow briefly takes hold into Tuesday afternoon.

Winds through the period will remain around 10kts or less, outside of Skagway which will see sustained up to 20kts through the evening. No significant LLWS expected through the period, but will see low level NW-ly winds through 06z across W PoW around 30 to 35kts on the back side of the low.

MARINE

Outside Waters: A building ridge with a low passing into British Columbia will keep strong breezes to near gales in the forecast with much of the outer coastal waters, diminishing by the early morning hours of Tuesday. Similarly, seas will be on the downward trend, with the localized area of swell passing into Dixon Entrance early this evening. Wave heights 10 - 17 ft at 10 seconds will diminish down to 5 - 7 ft at 8 seconds by the morning hours of Tuesday.

Inside Waters: Highest area of concern for the immediate short term is the southern half of the panhandle, specifically Clarence Strait. A westerly surge of winds to 20 knots will move through the channel shortly at time of writing, associated with the SW quadrant of a low pressure moving inland currently near Ketchikan. Southeasterly winds will rapidly shift to westerly to northwesterly winds up to 20 knots in Clarence, Chatham, Frederick, and Sumner with this surge. For Tuesday, somewhat more uncertain forecast particularly in the Icy Strait and Chatham Strait forecast. Daytime heating in SE AK, Yukon, and British Columbia will result in a thermal and tighter pressure gradient in the Lynn Canal area, with winds up to a fresh breeze. It is currently uncertain how far this will extend down into Icy Strait and Chatham Strait, with winds being anywhere between 10 and 20 knots around Sisters Island, Point Couverden, and Point Cravens.

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...None. MARINE...Gale Warning for PKZ641-661. Small Craft Advisory for PKZ022-642>644-651-662>664-671-672.