Last week’s summer heat wave wasn’t just hot. The weeklong stretch was one of the hottest periods in Umatilla County history.

Ann Adams, assistant forecaster of the National Weather Service, shared details on the heat, which stayed above 100 degrees for seven days starting July 25 and ending July 31.

The stretch is one of the longest periods of sustained heat in Pendleton history, Adams said. It’s the second year in a row the county saw summer records after an extremely hot 2021 summer. While most of that summer’s heat came in late June, it wasn’t as concentrated.

“We got pretty warm last year, but the days were spread out a lot,” Adams said.

There was no week in 2021 where every day saw temperatures rise above 100 degrees. Meanwhile, the week of July 25, 2022, is tied for the second-longest mark in Pendleton history at seven days.

The record for most consecutive days with high temperatures above the century mark is 11 back in August 1967. While that stretch was longer, the days were slightly cooler, if above 100 degrees can be considered “cool.”

The average high temperature in 1967 during their record stretch was 102.5 degrees. Conversely, the average high of the stretch this July was nearly 4 degrees warmer at 106.1 degrees. Of the three stretches of heat of more than a week in Pendleton history — the other being a week in July 1968 — the latest is the hottest on record.

The Hermiston area may have hotter annual averages than Pendleton, but this didn’t stop the heat from setting other records. The city saw the same seven-day streak of above 100 degree days starting July 25. While this stretch may fall to fifth place in terms of length — Hermiston dealt with 14 days of heat in June of 2015 — it still has the hottest stretch of the top five.

In addition to an average high temperature of 107.3 degrees, Hermiston set three daily records during the stretch. According to the National Weather Service website, the temperatures on July 28, 29 and 30 were all the hottest on record.

July 29 was the hottest day in recorded history for July in both cities. Pendleton saw a high of 111 degrees, while Hermiston had a high of 112 degrees.

The other two days saw slightly lower marks, but still set daily records. July 28 had a high of 108 degrees in Pendleton and 109 degrees in Hermiston, and July 30 was 110 degrees in both cities. Adams says these temperatures are about 15 degrees higher than the average high for the time.

The heat may have died down this week, but it should come roaring back by Monday, Aug. 8. Adams said temperatures should rise past 100 degrees again, with a high of 102 degrees in Pendleton and 104 degrees in Hermiston.