textproduct: Juneau

SYNOPSIS

Key Messages:

- Gale Warnings now posted for the Gulf of Alaska coastal waters off Prince of Wales Island Today.

- Wind Advisories are posted for much of the southern Alaska Panhandle today...mainly Sitka to Wrangell southward.

- Periods of heavy rainfall expected across the southernmost zones of Southeast Alaska this afternoon into the evening hours...but rain rates appear to remain below Flash Flood and Flood criteria levels. We will actively need to monitor rain rates in the south through the evening hours.

LONG TERM.../Monday through Thursday/

Conditions remain relatively benign across the panhandle with the potential for lingering showers to start off the week. Onshore flow in the upper levels, combined with a high pressure in the northern Pacific, is expected to keep a persistent marine layer in the gulf and bring damper, overcast conditions to the panhandle. Chances for the onshore showers look to last into early Wednesday morning, though there is some uncertainty for Wednesday into Thursday on if these showers will continue. If the upper level low moves southward enough to sit over the panhandle Wednesday, it will make the flow more offshore, and with the surface ridge amplitude offshore increasing and making the W-ly onshore flow become more NW-ly the precipitation chances would diminish over the panhandle and give a break for the area. A low will begin to develop in the far western Gulf Thursday, this system looking to bring more widespread rainfall back to the panhandle Friday.

AVIATION...12z TAFs

Generally prevailing MVFR expected over SEAK today into this evening, however there will be periods of IFR moving through as we get bands of heavier rains moving across the central and southern areas of the Panhandle this afternoon. We also have kept mention of LLWS in for most locations along and south of a Sitka to Petersburg line as we have 40 kt of SELY winds in the lowest 2 thousand feet AGL, Surface winds increase this afternoon across the southern Panhandle as the pressure gradient tightens as the frontal occlusion works up to the Outer Coast by late afternoon. /Garmon

MARINE

On the surface charts, we still note a 1003 mb low centered roughly near 55.38N and 145.33W. On the east side of the low...25 to 30 kt winds extend in a large swath eastward to Baranof Island, with sustained gale conditions to 40 kt being observed in ship reports off the coast of Prince of Wales Island this morning...and thus we do now have a Gale Warning posted for the Gulf waters off Prince of Wales. As the low moves slowly east though today, we expect the pressure gradient to increase for the inner channels of SE Alaska across the far southern portions of Chatom Strait, Sumner Strait, and Clarence Strait...and we have Small Craft Advisories posted for much of the southern inner channels through this evening. As we get into Tuesday, the pressure gradient will relax as the main area of low pressure starts to fill rapidly as it moves into SE Alaska, then high pressure builds in across the eastern Gulf of Alaska through Wednesday. By Wednesday, we should see southerly winds increase a bit to around 15 kts for the larger north/south stretches of Lynn Canal as well as Cross Sound, as was previously mentioned in the preceeding forecast packages. /Garmon

AJK WATCHES/WARNINGS/ADVISORIES

PUBLIC...Wind Advisory from 10 AM this morning to 7 PM AKDT this evening for AKZ323-327>330-332. MARINE...Gale Warning PKZ661-641. Small Craft Advisory for PKZ022-035-036-642>644-662>664-671-672.