Weather Synopsis for Monday night through Wednesday
A ridge of high pressure will remain centered offshore on Monday night and weak gradually through Wednesday, maintaining fair and dry weather. Surface high pressure has strengthened east of the Cascades Monday causing increasing easterly winds across the Cascade crest and through Stevens, Snoqualmie and White pass. Surface high pressure and cooling easterly winds have strengthened a temperature inversion with below-freezing temperatures returning to the passes and lower elevation areas, especially along the east slopes.
Some high clouds will continue to spill over the ridge at times through Wednesday, however, plenty of sunshine will persist both Tuesday and again Wednesday.
The current weather pattern typically causes extensive low clouds and fog along the east slopes and valleys, however, a lack of sufficient low-level moisture is limiting clouds and fog to just patchy areas.
The moderate easterly winds Monday should gradually subside Tuesday through Wednesday, allowing for warmer temperatures.
The next approaching weather system expected to undercut the offshore ridge has been consistently forecast to move southward well offshore Tuesday and head towards southern California Wednesday, missing the region entirely.