Memorial Day weekend weather: Warm, dry summer ahead as record-breaking El Niño builds in Pacific

The Pacific Northwest is on the verge of turning a corner toward a prolonged stretch of warm, dry weather, with long-range outlooks pointing to above-average temperatures and below-average rainfall extending through the summer and into early fall, according to one local meteorologist.

Scott Sistek, meteorologist and author of the Emerald City Weather Blog, told “Seattle’s Morning News” the region should begin seeing more consistent summer-like conditions after the Memorial Day holiday weekend, even as a weak weather system threatens to bring some rain to close out the long weekend.

“Saturday is great, mid-70s. Sunday is kind of like maybe a little cloudier, a little cooler, but still dry,” Sistek said. “And then the rain coming in Monday — the latest projections now say maybe it might hold off till Monday night or Tuesday, so we may be able to squeeze out our entire three-day weekend here without rain.”

Sistek cautioned that many models still show rain arriving Monday, but said there is a chance the system could hold off.

The approaching system, he said, is far less dramatic than recent rounds of severe weather that brought hail, isolated thunderstorms, and temperatures stuck in the 50s.

“This is more just like a little bauble, if you will, in the weather,” Sistek said. “It’s like a weak system.”

Beyond the holiday weekend, Sistek said longer-range outlooks paint a favorable picture for those eager for sunshine.

“If you look at a lot of the longer-range outlooks, even into like the rest of spring and into summer and early fall, they are all very adamant it’s going to be warmer than average and drier than average,” he said.

While occasional rain is inevitable, Sistek said sunny days will far outnumber wet ones in the weeks ahead. In any given six- to 10-day stretch, he estimated five to nine of those days would likely be dry.

“I think for the sun fans — the people who like the sunny skies and the warmth and the long dry stretches — this is looking like a pattern for you coming up for the next few months,” he said.

Meanwhile, a potentially historic El Niño is developing in the Pacific Ocean, and Sistek said every data update has reinforced the strength of the event.

“The raw numbers suggest this may be the strongest El Niño on record, or at least since the late 19th century,” Sistek said. “It’s kind of uncharted territory. We haven’t gone through an El Niño that strong before.”

Strong El Niño events typically push the jet stream southward, resulting in drier and warmer winters across the Pacific Northwest. Snowpack has historically suffered during such years, a prospect that has water resource managers and winter weather enthusiasts on alert.

“I don’t want to say it’s going to be 70 degrees this winter, but it’s definitely looking like a lot more of the 50-degree days than the 30-degree days,” Sistek said. “The warm fans have a lot to look forward to here.”

Sistek, a self-described lover of gray skies and rain, acknowledged the outlook is less exciting for those who share his preference for cooler, wetter conditions.

Manda Factor is the host of “Seattle’s Morning News” on KIRO Newsradio. Follow Manda on X and email her here. 

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