Portland's long, hot summer is heating up again.

After a record-breaking July, forecasts call for temperatures in the upper 90s by midweek - possibly as high as 100 on Wednesday and Thursday.

The city's third big heat wave of the summer begins Monday with temperatures breaking 90, according to the National Weather Service. Smoke from wildfires around Oregon and Northern California will turn the skies an unpleasant, hazy shade of brown.

Southerly winds aloft will bring smoke from wildfires burning over S. Oregon and N. California into our area. This will result in hazy skies over the area for much of the upcoming week. ☹️ pic.twitter.com/TkFjtnrCEE — NWS Portland (@NWSPortland) August 6, 2018

Portland logged 15 days when the thermometer broke 90 degrees last month, the highest tally on record for any month in Portland going back to at least 1940. The city endured nine consecutive days above 90, the second-longest streak on record.

On average, Portland has just 4.4 days above 90 each July.

August is usually Portland's hottest month and it has a chance of topping July based on early results and long-term forecasts.

The National Weather Service forecasts highs above 95 degrees on Tuesday, Wednesday and Thursday - falling back into the 70s by Saturday before spiking back up at the beginning of next week.

Rainy Portland barely got damp, recording 0.02 inches of precipitation owing to a brief spritzing on July 2.

-- Mike Rogoway | twitter: @rogoway | 503-294-7699