Mountain Weather Forecast

Time and Day: 0700 Saturday

The Snapshot: Clearing and cool today, light snow showers Sunday morning then cooler and clearing again.

The Science

Current Observations:  Very light snow flurries with no overnight accumulation are ending this morning. Satellite and radar images indicate clearing skies to the west. Temperatures on the upper mountain are in the low 20’s, and it is 26 in the base area. The barometer is up a few ticks from yesterday but generally steady.

The Forecast: WNW upper level flow is riding over the top of a high pressure ridge that is setup just off the Washington coast this morning. The ridge will amplify a bit today, bringing dry northerly flow and clearing skies. If it’s not going to snow, at least we should have a beautiful winter day.

The 36km 500mb WRF model for 7:00 am on Sunday is shown below (translation: 36km is the resolution, so a large area; 500mb is the atmospheric pressure level, so roughly 20k’ elevation; and, WRF is the Weather Researching and Forecast model).

We can see a shortwave low pressure cell just off the Washington coast, east of the obvious high pressure ridge. This is a relatively weak feature, and the result will be light snow showers Sunday morning, in cool northerly flow.

The Long Range: After the weak low pressure cell moves through the area tomorrow, the ridge moves further inland for dry and cool days Monday and Tuesday. There is some warming indicated for the middle of the week, with a moderate shot of snow possible Thursday and Friday.

24hr values daily 4am to 4am.

Precipitation: Saturday’s   24hr water: <.10   snow: trace Sunday’s   24hr water:  .10   snow: 1-2” Trend and Timing: Light flurries ending Saturday morning. Light snow showers Sunday morning.

Temperature: Low: 18    High: 25 Freezing level: 2000’ Trend and Timing:    Cool Saturday with some daytime warming, cooler Sunday.

Winds Base: W 0-5 Ridge Top: W 10-15 Trend and Timing: Light west winds Saturday and Saturday night.