Weather Synopsis for Saturday & Sunday

High pressure will bring mostly dry weather, ample sunshine, and a warming trend to the Pacific Northwest this weekend.

The ridge axis currently sits 500 miles or so off the Pacific Northwest coastline. This continues to allow weak disturbances to bring high and mid-level for the northern half of the forecast region. The few radar echoes Friday night only produced a trace of precipitation since this mid-level precipitation is falling into a dry air mass.

Cloud cover should gradually decrease from south to north on Saturday as the high expands toward the coastline. By Saturday night, the ridge axis should be over the west coast, forcing any precipitation north into Canada by around midnight. Before this occurs, Mt Baker and Washington Pass could pick up a trace to an inch of snow with a passing band of very light precipitation.

Freezing levels rise sharply across the region over the next 24 to 36 hours. Although these jumps appear drastic, the relative humidity values are very low. Therefore, these sharp temperature increases are unlikely to melt snow that isn't receiving strong, direct sunshine.

Easterly flow developing Saturday night helps temperatures warm initially west of the Cascade Crest and limits the development of inversions in these areas. By contrast, low-level inversions thicken to around 4500 ft east of the Cascades and through the mountain gaps. By Sunday afternoon, freezing levels rise above 10,000 ft in most areas, but do expect low-level inversions to create secondary freezing levels in the areas mentioned above with some possible low cloud as well.