It’s official… for only the fourth time in June history, the temperature at PDX hit 100 degrees today. To make the day even more special, the high temperature of 101 degrees at 2:37 p.m. was the highest June temperature ever recorded at PDX.
In several of the comments following my previous post, many of you are wondering how the temperature reached 101 when the highest hourly report was 97 (at 2pm and 3pm)? Well, during the hour between 2 and 3pm, the wind at the airport died down. That allowed the temperature to jump to 101 at 2:37pm during the calm conditions… but by the 3pm report, the wind had picked up again, dropping the temperature back to 97.
Discussion of the wind leads me to my next issue — the forecast high for tomorrow. The "thermal trough" (the axis of warmest air) will be right over the Valley tomorrow… and as a result, the wind will be significantly slower. And with 850 mb (5,000 ft) temperatures projected to be a degree or two higher tomorrow, I think 102 is a good number to forecast for Portland. I’ve had 102 on my 7 day forecast for Monday for a couple days now… and see no reason to change it.
Stronger onshore flow develops Monday night and Tuesday, resulting in a cooler afternoon Tuesday… and the rest of the week looks mostly sunny and warmer than average with highs between 80 and 85.
– Drew J