So after all the excitement the last 4 days or so, the heat wave has finally arrived. Looks like 93 was the high today at PDX. A collection of models, including our own RPM model here and the brand new 00z ETA, show a jump of about 10-12 degrees tomorrow. PLUS, the pressure gradient through the Gorge just switched to easterly. East wind is also blowing now at Timberline Lodge too. That plus a forecast of thermal trough in the Willamette Valley tomorrow makes me feel good about my warmest Day 1 forecast I’ve ever made for PDX. 104 for tomorrow. If so, that will be the warmest temp at PDX since the 105 in September of 1988…18 years ago!
Our RPM model also shows much warmer temperature tomorrow night, around 70 or above in the metro area. That would be interesting, since we haven’t stayed above 70 at night for years at PDX.
There’s no reason for any cooling Saturday, except our little model here (RPM) shows moisture working around the western edge of the upper-level ridge Saturday for lots of high clouds from thunderstorms. If that happens of course it’ll be cooler Saturday.
A very slow cooling trend next week as the ridge weakens somewhat, but summer temps continue. Try to stay cool…Mark