Mountain Weather Forecast

Weather Synopsis

Radar shows a Pacific frontal system reaching the Washington coast this afternoon. Unlike most Pacific frontal systems, this one will struggle to push its full wrath inland as the parent upper low sinks south and pulls away from our region tonight. This will focus the heaviest precipitation and strongest winds on the Olympic mountains, where a low level southerly jet will help crank out the highest snowfall totals on the eastern and southern flanks of the range. Lighter precipitation already manifesting itself in the form of occasional light snow or flurries over much of the Cascades will increase further tonight. A warm frontal feature will lift NE tonight, producing a dusting to up to 3 inches of snow, with perhaps 3-5" for the Baker area by by Saturday morning.  This has been a tricky system to nail down specifics with, so there's lower-than-normal confidence in the forecast tonight. 

As the low pulls south on Saturday, we should have some partial clearing or at least thinning of mid and high cloud cover.  Again, it's had to pin down who will see more sunshine than other areas. Offshore surface flow (east winds) combined with the general cyclonic (counter-clockwise) flow of the low pressure system that sets up to our south will help increase easterly winds on Saturday, with E-SE winds peaking Saturday night. Strong E-SE winds are likely from the Snoqualmie Pass area down to Mt. Hood.  This pattern will also drag much colder air entrenched on the east side of the Cascades west of the Cascade crest Saturday afternoon and night. The warmest locations will be the Olymipcs and areas well west of the Cascade crest. 

Sunday should see increasing clouds as the low pressure shifts inland and pushes some light snow northward. Mt. Hood and the south Washington Cascades are likely to see some light snow with high uncertainty regarding how much further north precipitation may reach.  Moderate to strong easterly winds should ramp down on Sunday.