The Inland Northwest will remain under a cool northwest weather flow aloft over the next several days with a series of waves moving through the flow and enhancing showery conditions. For today, drier and cooler air has filtered in from the north across central Washington and the Columbia Basin with mostly clear skies and locally breezy winds. Expect mostly sunny skies this morning turning partly cloudy by this afternoon with just a slight chance for an isolated shower with highs in the lower 60’s.
The next weather system will be spreading moisture across the Cascades on Thursday afternoon with an upper level trough sweeping across British Columbia. The Wenatchee Valley has a 20% chance of showers Thursday night with afternoon high temperatures once again in the lower 60’s.
On Friday, weather models are in fairly good agreement that a shortwave ridge will build over Northcentral Washington delivering a good chance of drying to that area, sunshine and warmer temperatures. Under mostly sunny skies Friday, we should see highs in the mid to even upper 60’s. By the weekend, the shortwave ridge will give way to a rather wet, but progressive brush with a sub-tropical plume of moisture from the southwest.
This should deliver some precipitation to the Cascades during the morning on Saturday spreading east during the day. Since this is a glancing blow of significant moisture, we don’t expect to see large precipitation amounts, with a 30% chance of afternoon showers Saturday with highs around 60 degrees.
By Sunday, the deep moisture will push south of the area, as an upper level weather trough shifts into the region and pushes a cold front across the Cascades into Northcentral Washington. Although this front will deliver drier air and breezy conditions, especially in the lee of the Cascades, much colder temps will likely lead to more showers over the eastern third of Washington and the Idaho Panhandle. High temperatures on Sunday will cool accordingly with readings in the mid to upper 50’s.
Our weather for Monday through Wednesday next week, expect occasional showers especially during the afternoon and evening time periods as several weak disturbances sweep over the region in unstable northwest flow. Partly to mostly cloudy skies in the weather forecast through early next week with a 20-30% chance of showers, afternoon high temperatures around 60 degrees with overnight lows in the mid 30’s.