Marine Weather and Tide Forecast for Perryville, AK

.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days 1 through 3: Tonight through Monday)...

An upper-level pattern featuring lows over the Bering Sea and Gulf of Alaska will continue to gradually shift inland through the weekend while the ridge over the Yukon-Kuskokwim Delta weakens.
This transition will bring a gradual cooling trend and a departure from the recent summertime convective pattern as increasing moisture spreads across Southwest Alaska ahead of an easterly wave.

This afternoon, scattered showers and thunderstorms are expected to develop along and just west of the Alaska Range as daytime heating combines with increasing instability. Initial convective development is favored over the higher terrain before storms expand westward through the afternoon and evening into the middle Kuskokwim Valley, including areas around Lime Village, Sleetmute and surrounding communities. A few storms may become locally strong enough to produce frequent lightning and brief heavy rainfall. While there remains some uncertainty in the exact timing of the easterly wave, the latest guidance continues to favor a slightly later arrival, allowing convection to become established before broader areas of showers overspread the region. Showers will become more widespread tonight with embedded thunderstorms continuing into Friday night before gradually diminishing east to west.

By Saturday, the Bering Sea low will continue tracking west toward the Southwest Alaska coast. Increasing cloud cover, cooler temperatures, and periodic shortwaves rotating around the low will support scattered showers across much of the Southwest Alaska while substantially limiting daytime instability.

By Sunday afternoon, a strong Bering Sea low approaches the western Aleutians including Shemya, Amchitka and Adak, bringing widespread rain across the region. The tightening pressure gradient along the western Aleutians may support increasing southerly winds, with gale-force winds possible. Meanwhile, Southwest Alaska will remain cool and unsettled with numerous showers continuing through the forecast period.

LM

.LONG TERM FORECAST (Days 4 through 7/Tuesday through Friday)...

The upper level flow for next week looks very progressive, with organized storm systems tracking from the Bering Sea to mainland Alaska. This general pattern tends to be cooler, cloudier, and wetter than normal. Nothing looks extreme for this time of year, especially for winds and precipitation amounts. Looking at the details, a large low and frontal system over the Bering Sea on Tuesday will quickly track to western Alaska Wednesday, with widespread clouds and precipitation across much of southern AK Wednesday through Thursday. As is typical, a new low will form in the Gulf Thursday and exit eastward Friday, with a drying and warming trend over southern AK as we head toward the 4th of July weekend. The one thing to watch will be potential for upper level "easterly waves" to affect Southcentral as the Gulf low exits, which could lead to additional rainfall into the weekend, especially for the Copper River Basin.

A new storm system will move out of the Pacific to the Aleutians Thursday night, then weaken over the Bering Sea Friday through Saturday. At this point, it doesn't look like there will be much impact on southern Alaska from this system. While forecast confidence is always fairly low a week or more out in time, at this point none of the model guidance shows any significant weather features for the 4th of July weekend. Instead, it looks seasonable with a chance of diurnal convection. Stay tuned.

-SEB


AVIATION

PANC...VFR conditions and light winds will persist through much of the TAF period. There is a chance for rain showers to drift over the terminal through this evening, with brief dips into MVFR conditions possible through tomorrow morning.