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With mostly sunny skies in the forecast, and the rainy season approaching, Washington state’s highway department is sending contractors back to work on the Eastside this weekend, where drivers are sure to be delayed.

The most disruptive job is another round of toll-lane construction on northbound I-405 in Renton, where all northbound lanes will close between Southport Drive/Exit 5 and Coal Creek Parkway/Exit 10, from 11:30 p.m. Friday, Sept. 18, until 4 a.m. Monday, Sept. 21.

The official detour runs as usual from Highway 900 in north Renton through Coal Creek Parkway in Newcastle, but a sewer project there may block a lane this weekend.

The I-405 toll-lane addition from Bellevue to Renton is already two years late, and the state is loath to skip any more dry weekends — after standing down during the Apple Cup and Labor Day — and risk more delays in the $705 million project.

“We are just at the crescendo of a lot of work,” said RB McKeon, regional spokesperson for the Washington State Department of Transportation. She also mentioned the five-week World Cup period when most highway jobs were suspended, as another reason WSDOT is playing catch-up now.

Eastside drivers will find another slowdown at eastbound Highway 520 in Redmond, where two right lanes close eastbound at West Lake Sammamish Parkway from 5 a.m. to 1 p.m. Saturday and the same hours Sunday.

Meanwhile, two lanes of northbound I-5 in Seattle remain blocked at the Ship Canal Bridge for a long-term concrete deck repave, but unlike last weekend, the express lanes will be pointing northbound to provide a bypass route.

An overnight three-lane closure is planned on northbound I-405 from Kirkland’s Totem Lake area to Bothell at Highway 522, from 11 p.m. Saturday to 7 a.m. Sunday, to include possible 15-minute full closures.

“Travelers should expect longer and less predictable trips. Delays may occur in new places and at new times,” WSDOT says, as the agency juggles its shifting construction zones the next few weeks.

Previously announced lane closures on eastbound I-90 in Bellevue, to refurbish expansion joints over Richards Road, were canceled Thursday afternoon. After losing last weekend to rain, contractors don’t think they can repair the whole bridge this month, so it will happen later, state officials said.

Another weekend job, on Kirkland’s Northeast 85th Street where it meets I-405, is also postponed.

Highway 520’s eastbound offramp to Montlake Boulevard is on pace to reopen at or before 8 a.m. Saturday. That will bring relief to 14,000 daily users and allow plenty of time before the Huskies host Eastern Washington at 4:15 p.m.

WSDOT encourages people to check its online traffic map, download its app or subscribe to project email feeds, because plans can change on short notice.

Correction: This story was updated to remove an I-405 southbound closure for Sept. 19-20.