Upper level weather system will move south into the Pacific Northwest later today bringing a significant change in our weather pattern. This morning will be fairly quiet with a slow increase in clouds throughout the day. It will also be a bit breezy this afternoon with west winds blowing 10-20 mph with gusts as high as 33 mph. Afternoon temperatures will top out in the lower 60s for most of Northcentral Washington. This is about 5 to 10 degrees below average…but by Saturday we will fondly remember these `warmer` temperatures. Rain will develop in the afternoon with the low moving in, first in Western Washington and then for the rest of the state by tonight with 90% chance of rain for the Wenatchee Valley.
On Saturday, the low remains near the Washington/Oregon border and will continue to bring our area bands of moisture and fairly strong winds both Saturday and Sunday. There is an 80% chance of rain on Saturday and a 60% chance on Sunday with afternoon highs near 50 degrees on Saturday and only in the mid-40’s for highs on Sunday. By Saturday, snow levels will be between 2500-3500 feet, with another drop to 1500-2500 feet Saturday night into Sunday morning. Cannot rule out some rain/snow mix down along the Highway 2 corridor during the afternoon, but it should not be accumulating. Saturday night most locations along Highway 2 and northward will see rain/snow mix, with possible very light accumulations of less than an inch, mainly for grassy surfaces. The mountains however could see 6 to 12 inches of snow. Lots of potential impacts from this highly unusual September storm. People keeping gardens going, or have not harvested their bounty: it would be best to either protect your sensitive plants or pick and pull your items. Any outdoor enthusiasts: Dress for the weather. It is going to feel like winter, a fleece will likely not cut it. Boaters: be prepared for choppy waters, white caps. Columbia Basin People: Not a lot of precipitation is expected south of a line from Ritzville to Vantage. So, any recently plowed fields could produce some blowing dust Saturday afternoon and evening. Travelers: Be prepared for winter driving conditions, especially across the higher terrain. Even in the valleys during the late night and early morning hours, roads will likely become slick.
Monday and Tuesday: Confidence is growing that widespread killing frost will occur across large portions of the Inland Northwest Monday morning and Tuesday morning. If a killing freeze doesn`t occur Monday morning around Moses Lake and sheltered cold pockets around Wenatchee, chances are good that a freeze will occur Tuesday morning.
Wednesday and Thursday: Temperatures will slowly moderate with mostly sunny skies and afternoon high temperatures in the upper 50’s.