textproduct: Anchorage

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)

Discussion:

The primary weather feature of note this morning is the modest low that is rotating over the eastern Gulf. This low will continue to drift northwards this morning before beginning to retrograde back west over the northern Gulf later tonight. Abundant cloud cover across the Gulf with the northern extent rotating westward into the Copper Basin overnight...which has helped to keep temperatures from plummeting in the lower river valleys. Further west across inland Southcentral, a ridge of high pressure has allowed for mostly clear skies for the western Kenai up through the Mat-Su Valleys. Given good radiational cooling and lack of wind, a few pockets of fog may develop by mid-morning for some of the these areas. An fog that does develop will scour out by late morning. Low stratus over the Copper Basin and increasing mid-level cloudcover may spark some light seeder-feeder snow this morning, though a greater chance for light snow will arrive by tomorrow morning for the southern Basin.

The aforementioned low will bring coastal showers and gale to storm force winds along the near-shore waters of the northern Gulf. The center of the low is progged to become more compact as it nears Prince William Sound, though the GFS appears to be the most aggressive with this solution with the Canadian in hot pursuit. As the low progresses westward, several shortwaves will rotate around the center with light precipitation spreading into the Southern Copper Basin by late tonight. The vertical temperature profile is cold enough that the precipitation type will be all snow. Light snow will spread up towards the center of the Basin Saturday morning before winding down Saturday afternoon and evening. When all is said and done, the southern half of the basin could see about 1-3 inches. Increased precipitation chances for Prince William Sound for the weekend with coastal mountains seeing snow and rain at lower elevations. A few showers may make it over the mountains, but any precipitation will remain light and will end by late Saturday evening as a new surface low deepens over the Barren Islands.

- PP

AVIATION

PANC...VFR conditions and light northerly winds are expected to continue through the TAF period. There is a low chance (10 to 20 percent) of fog in the morning as clear skies lead to strong radiational cooling and development of steam fog over the inlet. Any fog that does develop this morning is expected to dissipate by late morning to early afternoon as dewpoint depressions widen by then.