High temperatures peaked at 101 in Medford Tuesday afternoon. Grants Pass was in the upper 90′s, while Klamath Falls hit 90. Tuesday was the peak of the heat wave with most of the viewing area seeing temperatures between five and fifteen degrees above average.
The high pressure air mass that has been expanding over the region the last several days will weaken into Wednesday. A cooler air mass is going to move in and drop temperatures gradually through Friday. By the end of the week, more seasonal temperatures are expected. Thunderstorms are going to be a minimal threat for the Cascades, Siskiyou County and the East Side Wednesday afternoon and Thursday afternoon. Even so, these will be pretty isolated although the greater chance will be Thursday when instability is higher.
Following Friday, another heat wave is going to begin. This time, triple digit temperatures are expected in the Valley and Siskiyou County.