Sigmund Seroka

Through the weekend not much changes except a cloud or two that will develop over a few areas Sunday and Monday.

Storms are likely to start after 1 p.m. Wednesday between Ellensburg and Wenatchee in Washington and between Ukiah and Pendleton in Oregon.

Excessive Heat Warning for the Yakima and Kittitas Valleys from until 10 PM Thursday… Temps 95-108° Heat exhaustion and heat stroke are likely

A weak cold front associated with the upper low will drop temps and increase winds heading into the middle of next week.

This ridge will force an upper low in the Gulf of Alaska and another smaller low offshore to remain away from our area until Sunday night.

A large ridge of high pressure to our south is keeping us hot today but an incoming trough to our northwest will cool us significantly starting tonight.

Highs this afternoon in the mid to low 90s as the smoky skies will raise humidity and block some sunshine. The sun will shine through the decent haze while smoke continues to fill up Eastern Washington and Oregon from regional wildfires. A large ridge of high pressure to our south is keeping us in its perimeter, but an incoming trough to our northwest will cool us significantly starting with another front Wednesday night. Gusts in the gaps in the Cascades will be 25-35 mph Wednesday and Thursday afternoon in the Kittitas and Yakima Valleys plus the Columbia River Gorge. This will push in the cold air that will drop our lows temps for the second half of the week. Lows will be in the mid and upper 50s with a fresh breeze and poor air quality.

Some relief for fresh air could be seen this afternoon as winds from the west ahead of a cold front will help push much of the wildfire smoke further east.

Updated Air Quality Alert for Umatilla and Morrow Counties in Oregon plus Yakima, Chelan, Okanogan, Ferry, and Stevens Counties in Washington until further notice…

The upper low is gradually sliding east through British Columbia and filling slowly from a large ridge in the Eastern Pacific. The ridge over the Pacific Ocean will have a transient impact on the PNW through the weekend into next week. While the pressure gradient is pretty relaxed, there will be some gusts in the Tri-Cities Sunday afternoon that will measure out to 15-25 mph. Model runs from the last few days look to favor these speeds in that range so there is no concern for any of the boats other than a little chop on the Columbia River. Weak low-level convergence will lead to rising air through the middle of the week and warmer temps in the mid 90s through Thursday.