Scott Sistek is providing updates through the storm on Twitter @ScottSKOMO
Updated Saturday 8:45 a.m.
A potent storm that might be a first for August -- or at least a first in summer in several years -- is bearing down on the Pacific Northwest Saturday, bringing November-like storm conditions before Bumbershoot musicians have probably even figured out their sets.
High Wind Warnings are in effect for much of Western Washington, including the Seattle/Greater Puget Sound area, the Northwest Interior and the coast. Gusts on the coast were already occurring early Saturday morning with a peak gust at Hoquiam of 54 mph as of 8 a.m.
The storm will gradually make its way north and east through Saturday morning, spreading heavy rains and strong winds inland, with peak winds in the Puget Sound region occurring around late morning into the early afternoon hours. Gusts in the Seattle Metro area and much of the rest of the I-5 corridor are expected to reach 40-45 mph with perhaps a few isolated gusts to 50 mph. One exception is the Hood Canal/Admiralty Inlet/Whidbey Island areas which could see gusts to 55 mph.
Those wind speeds are pretty routine for November and December. But for August, 45-55 mph winds are quite rare, and have potential to do more damage than usual.
The trees are still heavy and full of leaves, and the first windstorm of a season tends to be the one to break off all the more susceptible branches that weakened over the summer. Thus, we tend to see more damage with lower wind speeds early in the season than in late fall and winter when the trees are bare, and it's a good idea to be prepared for scattered power outages in the midday and afternoon hours.
In addition to the wind, drenching rains will be a factor as well. Heaviest rains will fall early Saturday morning, with perhaps a brief lull in the mid-late afternoon when the wind kicks up, then a secondary wave of rain is expected in the evening. Winds and rain will call down Saturday night.
All told, much of Western Washington is expected to receive well over 1" of rain by Sunday morning, with some spots in the mountains getting 2-3 inches of rain. The National Weather Service says in the history of recorded Seattle weather -- which is back to 1891 -- there have only been 11 dates in August to have more than 1" of rain, and never two in the same year. We've had one day already this year at 1.50" on Aug. 14 when we had all those thunderstorms. Could another weather record fall this summer -- only this one would not be heat related?
Winds and rain will calm down Saturday night.
We'll call it a relative lull for Sunday, but it'll still be cool and cloudy with frequent light showers through the day. Highs both days will be in the mid-upper 60s.
Another wave of light rain returns for Monday and stalls over the region for Tuesday. This will just be typical Seattle light rain and much less stormy. Highs will stay in the mid-upper 60s.
Showers and sunbreaks will be more the rule for the balance of the week with highs in the upper 60s to near 70. So while it might seem like Thanksgiving time around here, remember you do only get one extra day off for Labor Day :)
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