Weather for the holiday weekend will start off rather unsettled as an area of low pressure drops into Northcentral Washington from British Columbia riding down the front side of a large high-pressure ridge. This weather system will bring numerous showers and chance for thunderstorms across Washington. Wenatchee Valley forecast for today calls for cloudy skies, a northwest wind 10-15 mph, a 50% chance for showers with afternoon highs today cooler, in the mid 60’s.
A second weather system drops in from the north on Saturday and reinforces the cold air aloft and more instability. This low will take more of a westerly track down the coast but will likely result in widely scattered showers and thunderstorms across the Cascades and northern mountains. For Saturday, expect mostly cloudy skies and a 50% chance of scattered showers with cool afternoon highs only in the lower 60’s.
Saturday night and through Monday, the upper level low from Friday and Saturday will slowly track south along the Oregon/California coast Saturday night and Sunday, then track east into Nevada on Monday.
Plenty of moisture is expected to wrap around the low into Sunday as well with mostly cloudy skies, a 40% chance of showers and afternoon high temperatures warming into the lower 70’s.
By Memorial Day Monday, conditions will be dry with the start of a major warming trend as high-pressure builds back into Northcentral Washington. Temperatures will jump into the mid-70s to low 80s on Monday under mostly sunny skies.
Tuesday through Thursday, temperatures will continue to slowly rise with high temperatures in the lower 80’s at first, warming into the mid and upper 80’s on Wednesday and Thursday with mostly sunny skies each day.
The ridge of high pressure will begin to flatten Thursday and Friday and this will result in slightly cooler temperatures and the potential for cumulus cloud build-ups on the ridges and possibly light showers in the mountains.