First day of Portland Public Schools new year comes during a one-day heat spell Tuesday

Portland’s one-day heat advisory happens to fall on the first day of school for more than 44,000 Portland Public School District students. The heat advisory is in effect from noon to 9 p.m. Tuesday.

The National Weather Service says daytime high temperatures of 95-100 are possible all over the metro area as well as in the central Willamette Valley, western Columbia River Gorge, in Clark County and up the Interstate 5 corridor to Cowlitz and Columbia counties.

Kids waiting at the bus stop early Tuesday won’t need a jacket. Temps by 8 a.m. are likely to be around 65 degrees. Lunchtime will be warm at 88 degrees and temperatures at dismissal times, depending on the schedule, will be between 94-97 degrees. Average temps for late August are in the low 80s, but several years have suffered through temps in the triple digits nearing the first day of school, including 1986, 87, and 88 and a temp of 98 on Aug 27 of 2019.

Portland’s overall high temp will likely reach 98 degrees Tuesday.

The hot spell is only expected to last through Tuesday, but the rest of the week will be warm with temperatures in the low 90s possible through Friday.

The weather service says a slight cool-off comes Tuesday night into Wednesday morning with the deepening of marine clouds along the coast. The beaches could even see some drizzle. Valley temperatures will remain very warm under sunny skies. Most metro areas will see temps in the 92-94 range. Portland should see a high of about 92 degrees.

Thursday will mostly mirror Wednesday with temperatures nearing 92 degrees under sunny skies.

The jury is still out on max high temperatures Friday and Saturday. It’s likely both days will be a few degrees cooler than earlier in the week, but still above normal for the first days of September. There are chances of drizzle along the coast and some of that cooler air will make its way into the valleys.  Friday should be sunny, with a high of around 89 degrees.

Extended forecasts are showing chances of additional cooling Saturday and Sunday.

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