Seattle breaks 30-year heat record as Western WA enjoys warmest days of 2026

The warmest weather of the year thus far continues Monday before a cooling trend begins Tuesday. High temperatures Monday are expected to be close to the warm Sunday temperatures that had many interior locations reaching 80 degrees or better.

The Seattle-Tacoma International Airport (SEA) broke its daily record high of 77 degrees set in 1992, climbing to 81 degrees. Olympia topped out at 84 degrees, topping its previous record high of 80 set in 1992.

Higher pressure aloft over Western Canada, combined with low-level offshore flow toward the Pacific Ocean across Western Washington, pushed high temperatures well above normal. The average high temperature for early May is in the lower to mid-60s.

However, the low-level offshore flow is anticipated to weaken and become weak onshore Monday night and Tuesday, and continue through this week. Marine clouds with cooler air will surge inland. Yet, the marine cloud layer is expected to be rather shallow, permitting afternoon clearing each day through Thursday.

High temperatures are forecast to remain above average, ranging from the upper 60s to mid-70s, with the exception along the coast, where highs there are in the lower to mid-60s.

Any rain in sight?

The high pressure aloft is expected to shift inland late in the week, allowing a weakening Pacific weather system to move onshore, bringing a threat of rain and cooling temperatures into the mid- and upper 60s. But that threat will be short-lived, as higher pressure rebuilds, bringing a return to drier and warmer weather late in the weekend.

Longer range weather charts and the two-week weather outlook reflect essentially no significant rain through at least the middle of this month. In fact, temperatures are expected to remain above normal through much of the first half of May. High temperatures of 70 degrees or better are forecast to be rather common.

April recap

Across Western Washington, April finished below average for rainfall. SEA was about four-tenths of an inch drier than normal for the month, while Olympia, Bellingham, and Hoquiam all finished more than an inch below normal. Forks on the north coast was even drier, finishing more than four and a half inches below normal for the month.

Despite a wet March, much of Western Washington has once again dropped below average for the year. SEA finished April about a third of an inch below average since Jan. 1, while Olympia was more than two inches drier than normal.

The latest drought monitor shows much of Eastern Washington in moderate drought, while west of the Cascades remains in good shape at this point. Yet, the meager winter mountain snowpack and seasonal weather outlook through the summer, with good odds of warmer- and drier-than-average conditions, point toward Western Washington joining the eastside in developing drought conditions.

The first half of this month looks to remain mainly dry with warmer-than-average temperatures. The time has come to water the yards.

Ted Buehner is the KIRO Newsradio meteorologist. Follow him on X and Bluesky. Read more of his stories here.