A rapidly intensifying low pressure system is moving north through the Gulf of Alaska on Wednesday afternoon. It is forecast to make landfall on or near Alaska’s Kenai Peninsula early Thursday morning.
Off the coast of Alaska, hurricane-force winds are forecast to extend eastward from the Kenai Peninsula toward the southeastern portion of the state. Wave heights may exceed 30 feet (9 meters) in spots.
Onshore, heavy snow is forecast for the mountains bounding the coast from about Anchorage south to near Vancouver, British Columbia. Over the next three days, higher elevations are likely to see over three feet (one meter) of new snow. The Washington and Oregon Cascades aren’t expected to see this much though modest totals are possible in the North Cascades and on the volcanic summits.
Strong wind will accompany snow close to the low’s center in Alaska. Thompson Pass near Valdez is under a blizzard warning for 28 inches (70 cm) of new snow this afternoon and evening with wind gusts to 45 mph (70 km/h). Snow levels will be rising with the low moving north, creating a flood threat for some lowland areas including around Anchorage.
The low pressure system is draping a cold front across the East Pacific. Thursday morning this front will extend down to about the same latitude as San Francisco. While the center of the storm moves north and later northwestward the cold front is headed eastward.
The Pacific Northwest coast will start to see rain around or just after noon on Thursday. Weather conditions on the coast won’t be nearly as severe as Alaska is experiencing but those on Vancouver Island and the Oregon and Washington coasts will see modest winds especially on beaches and headlands.
Thursday afternoon and evening will be wet in Portland, Seattle, and Vancouver with steady rain transitioning to showers after the front passes through. Most of the moisture will be wrung out by the Cascades but drizzle or light rain showers are possible in the Columbia Basin on Friday morning.
For the Pacific Northwest, this is the first of a string of storms forecast to bring more rain and mountain snow through the weekend and into early next week. The next cold front comes early Saturday, sourced from another Gulf of Alaska low but Alaskans will find that storm to be not as strong as the one impacting them today and tonight.
Drought conditions continue to persist in most of the Pacific Northwest but have been slowly improving so far this fall. The incoming parade of storms will help continue this improvement. In Western Washington, Northwest Oregon, and most of the Palouse November is the wettest month of the year on average. For most other Washington and Oregon lowland locations, December is the wettest on average.
The featured image is satellite imagery from Wednesday afternoon via the College of DuPage.
