Get ready for a big warm-up: Record-breaking temps could crack 90 degrees in parts of western WA

It may be cool and wet now, but a big change to much warmer and drier weather is in store by this weekend and into early next week in western Washington. This change will feel quite significant since we have not had any such warm weather since September 16 last year, when the Seattle-Tacoma International Airport (SEA) reached 91 degrees.

Starting Wednesday, higher pressure aloft is forecast to begin building over the Pacific Northwest, with the clouds clearing and temperatures rising.

By this weekend, high temperatures are expected to climb well into the 80s with some of the usual warm locations in western Washington cracking the 90-degree mark – the warmest so far this year.

The first World Cup game in Seattle is set for Monday, when the weather conditions will be hot.

For cooler conditions, Puget Sound and coastal shorelines will offer relief with readings generally in the 70s.

High temperature records will be at risk. For example, at SEA, Sunday’s record high is just 86 degrees, set back in 1988. Monday’s mark is only 88 degrees, established in 1963.

At Paine Field in Everett, the high temperature record on the 14th is just 77 degrees, set in 1999, and on the 15th, 78 degrees in 2015. In Olympia, the record on the 14th is 88 degrees set in 1988, and on the 15th, also 88 degrees in 1963.

Steps to take during hot weather

If unable to travel to cooler locations, here are some steps to take to be cooler and avoid any heat-related health concerns.

• Seek air-conditioned facilities such as shopping malls and theaters. In the 1990s, only about 15% of homes had air conditioning. Today, that percentage has risen above 40%.
• Stay hydrated by drinking plenty of water and avoiding alcoholic beverages.
• During the heat of the day, avoid strenuous activities like running or jogging, and if working outdoors, take breaks and again drink plenty of water.
• Avoid leaving children and pets in cars, even if for just a few minutes. Temperatures inside a vehicle can soar to well above 100 degrees in less than 10 minutes, even with the windows open. Remember – Beat the Heat, Check the Back Seat!
• The most vulnerable to prolonged heat are the elderly, the very young, and those with heart-related medical conditions. Check on these family members, friends, or neighbors to help ensure they are doing OK.
• Wear light, loose-fitting clothing to help reflect the heat.
• Area waterways also offer cooling relief. Just remember to wear a properly fitting U.S. Coast Guard-approved life jacket. Area waterways are still cold, only in the 50s to the lower 60s. Accidentally falling into the water results in cold water shock, like stepping into a cold shower, which is the leading cause of drownings across the state.

Heat risk tool

Because we have not had such hot weather since late last summer, the big warm-up is going to have rather dramatic health impacts from the sudden rise in temperatures. The majority of heat health issues, such as heat exhaustion or even heat stroke, occur early in the warm season.

Be sure to monitor the latest weather forecast and information about this hot weather. The National Weather Service has a publicly available heat-related resource called HeatRisk. This resource is a color-numeric index that shows a forecast threat of heat-related impacts.

HeatRisk takes into consideration how unusual the heat is for the time of year, the number of days for the expected hot weather, including not only daytime temperatures, but also overnight temperatures, and the elevated risk of heat-related health impacts.

More 90-degree days these days

In the 20th century, Seattle averaged only three days per year reaching 90 degrees or more.

So far this century, that average has risen to five days per year, and in just the last 10 years, the number of days hitting 90 degrees or higher is now eight days per year.

Conditions are dry

The rain deficit across the state continues. Over 60% of western Washington is considered abnormally dry, according to the U.S. Drought Monitor.

Much of the state east of the Cascades is now in moderate or severe drought. The upcoming combination of hot weather and dry conditions means the region is at greater risk for wildfires.

Wildfire conditions and precautions

The ramp-up in temperatures is going to simply amplify the wildfire potential through at least early next week.

Some wildfire precautions:

• If camping, be sure the campfire is cold before leaving the site.
• For many counties and fire districts statewide, check with local authorities to learn the latest details regarding any burn bans.
• If towing, be sure to tighten tow chains to avoid sparks from chains dragging on roadways.
• Avoid tossing burning materials such as cigarettes out of vehicles. This behavior is how many roadside fires get started.

The weather pattern is anticipated to moderate by the middle of next week as cooler low-level onshore flow from the Pacific Ocean develops. Yet, the latest weather outlook through mid-June reflects good chances of warmer and drier conditions than average. So warm, dry weather is anticipated to continue until the calendar at least reaches the summer solstice on June 21.

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