High Wind — Matanuska Valley, Alaska

2003-03-12 to 2003-03-14 · Matanuska Valley, Alaska

Wider weather episode

A "Bora" type windstorm hit much of the Matanuska Valley, Anchorage and portions of the Kenai Peninsula.Very cold air funneled down the Matanuska Valley, driven by a large high centered over the Chukotsk Peninsula. A combination of strong convergence aloft, a tight surface pressure gradient, and terrain forcing brought hurricane-force winds to the ground over a large portion of greater Anchorage. Damage reports were numerous and included small planes, roofs torn off buildings, car ports caving in and siding blown off. Power outages of 9 hours or more were reported. Communications were also impacted. Lots of broken signs, traffic lights rendered inoperable, partial roof collapses, lost roofing shingles and garbage cans scattered all over west Anchorage and the Palmer area.When the 109 mph gust hit the Ted Steven's International Anchorage airport at 10:42 pm, the tower was abandoned and the airport closed to incoming traffic. Just prior to that, an Alaska Airlines flight received clearance to land with winds "three five zero at eight zero knots (92 mph)". Flights right behind it decided to go to Fairbanks and Juneau! In all, around 15 flights were diverted to Fairbanks, which became a parking lot for 747s Thursday.Winds gusting close to 60 mph whipped across the western Kenai Peninsula also, creating 'red flag' conditions and spreading small fires into significant ones across the dry ground. Largest reported fire reached 100 acres north of Anchor Point. Scattered power outages were also reported across the area, including one larger one around Fritz Creek (on the outskirts of Homer).In the Valdez area, gusts at the airport reached an estimated 100+ mph, ripping roofs off several structures and breaking glass in buildings and cars. Overall, at least 14 vehicles around the Valdez airport were damaged.In addition, temperatures around zero combined with the strong winds to produce wind chills near 45 below zero. The cold air, driven into buildings by the strong winds, also froze many water pipes...which then burst, adding to the damage estimates.

Source: NOAA Storm Events Database, event_id 5340798. Narrative written by the NWS forecast office that issued the report.