Area Forecast Discussion
Issued by NWS Anchorage, AK
Issued by NWS Anchorage, AK
476 FXAK68 PAFC 161328 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 528 AM AKDT Sun Jun 16 2024 .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: Sunday through Tuesday)... The overall weather pattern is similar to yesterday with lots of clear skies in the morning (except right along the north Gulf coast of the eastern Kenai Peninsula) and warm temperatures expected across the region. Afternoon showers and thunderstorms are expected once again, but there are a few key differences from yesterday in this area. The first is that yesterday`s thunderstorms that developed over Anchorage and the Kenai Peninsula were largely influenced by a very weak 500 mb low that developed near the north Gulf coast and is northeast of Kodiak Island as of this writing early Sunday morning. While this low was weak, as was mentioned in yesterday morning`s forecast discussion, it was enough to bring more organized thunderstorms for these areas and is still producing some thunderstorms northeast of Kodiak Island early this morning. Today will not have this low so even though the atmosphere remain unstable, the thunderstorm development should be more random in nature with elevated heating over the mountains being a key trigger today. The atmosphere over the Copper River Basin is not as unstable as areas farther west, but there could still be a few isolated thunderstorms n the area again today. For Monday, temperatures will begin to cool a little across the region, but still remain pleasantly warm. Thunderstorms for Monday into Tuesday are more likely to be relegated to along the Alaska Range with some showers over elevated terrain over the rest of southcentral. Tuesday will also bring a pronounced change to Kodiak Island as a front will move over the Island and bring rain with it. && .SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days 1 through 3)... Upper level ridging shifts northwards as a series of shortwaves move through Southwest Alaska over the next few days. Convective activity is expected to produce some wet thunderstorms today and Monday afternoon along the central/eastern portions of the Lower Kuskokwim Valley and Bristol Bay as well as along the Western Alaska Range. Thunderstorm activity becomes more widespread Monday afternoon/evening potentially pushing further west into the Kuskokwim Delta. Small craft winds near the Eastern Aleutians will continue diminishing as the front over the area weakens through today. Rain chances return to the Eastern Aleutians Monday as a weak surface low spins south of the Aleutian Chain. && .LONG TERM FORECAST (Days 4 through 7: Wednesday through Saturday)... A broad upper-level low extending along and south of the Aleutian Islands and Alaska Peninsula on Wednesday shifts eastward through the end of the week. Rainy conditions associated with a weak front shift from the Alaska Peninsula, Kodiak Island, and Bristol Bay into the Gulf of Alaska for Thursday. A series of shortwave troughs embedded in the broad upper low lift into southern mainland Alaska and then rotate westward on Thursday and Friday, bringing a slight cool down and wetter conditions. Increased lift afforded by these shortwaves will lead to areas of more widespread, steadier rainfall across portions of Southcentral and Southwest Alaska. For Friday, a North Pacific low passes south of the Gulf of Alaska, approaching Southeast Alaska/Haida Gwaii by Saturday. The low pressure draws theta-e ridging southward from Interior Alaska, allowing a return to warmer weather and thunderstorm potential for the southern mainland next weekend. Out west, surface high pressure over the Bering Sea will likely support widespread fog and low stratus across the western and central Bering on Wednesday and Thursday. A North Pacific low, potentially gale-force, begins to push into the western/central Aleutians for Friday, scouring out some of the fog, but bringing windier, wetter conditions. Heading into the weekend, the low progresses north and east, spreading rain and gusty southeasterly winds potentially as far as the Alaska Peninsula. Quesada && .AVIATION... PANC...VFR conditions and light winds will generally prevail throughout the TAF period. The potential for showers and even a thunderstorm late this afternoon and evening does exist. However, the upper level flow is more easterly instead of northeast which will make it more difficult for any thunderstorm that develops over the Chugach Mountains to reach the terminal. && $$