Note: Announcement at the End
It is not unusual for the first notable snow to fall in the Northwest mountains around the middle of October, and this year will be no different.
Today's view from the top of Crystal Mountain, east of Mt. Rainier, is snow-free (see below). It won't be that way for long.
A pulse of cold air will push into Washington State on Sunday and Monday, accompanied by moisture coming from the Pacific-- the result will be snow above approximately 4000 ft, with some flurries reaching 3000 ft. And plenty of rain in the lowlands.
This is just the start.
By Tuesday morning, substantial snow will fall on the Cascade crest and its eastern slopes....as well as the mountains of NE Washington. At some locations: 5-10 inches!
Extensive snow over and to the east of the Rockies.
Looking at the forecast temperatures at Stampede Pass, at around 4000 ft in the Cascades (below), we see the high temperature on Sunday will only reach 38°F. With wet snow, it won't feel like summer anymore.
The origin of the cool air? From the Arctic!
On Saturday and Sunday, cold air will push southward over western Canada. The map below shows the predicted temperatures around 5000 ft (850 hPa pressure) with the purple colors indicating very cold air (below 20°F). From the Arctic to you!
On Monday morning, with low pressure along the Oregon coast and cold, high pressure over British Columbia and Alberta, cold air will be pushed westward across northern WA state (see map around 5000 ft below, with blue colors indicating cold air). Winds are also shown, as are heights on the 850 hPa pressure surface (you can think of it as pressure around 5000 ft).
This represents the end of our wildfire season--which will be welcome by all.
Announcement
I will hold a special online Zoom session at 10 AM on Saturday for Patreon supporters. Will answer questions and talk in detail about the outlook for the coming winter
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Great reporting as always Cliff. Thanks.
ReplyDeleteThe bears will be pissed
ReplyDeleteNot sure they mind. They're pretty well insulated. They probably feel like you do an hour before bedtime. Looking for a den in which to hibernate. Perhaps they are already looking forward to spring. Except the lowland bears probably don't hibernate.
DeleteI had long been under the impression that all of our region's bears hibernated in the winter. While that may have been the case at one point, it seems the lowland bears are being more active in the winter these days, especially on the coast, where sightings have occured in in the traditional hibernation months of November and February, and in the Quinault area, where I actually observed fresh scat on the rainforest trail (the one on the south side of the lake about a mile or so off of 101) in the middle of January a couple of years ago. I've also heard about a bear that stayed active during a recent winter on the Key Peninsula.
DeleteI welcome our snow overlords. Please make yourself at home.
ReplyDeleteOh yeah; we're definitely due. The overnight lows have been sliding, as they must ("cometh the seasonal Big Dark"). 'Much appreciate the heads-up as to extent and timing.
ReplyDeleteIts been down to 45 at the coast overnight, and our daytime highs were expected to be below 60 today for the first time in months. The seasons are most certainly changing.
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