Aliens, runners and road closures: Expect traffic this St. Patrick’s Day weekend

Tis the season for all things green! St. Patrick’s Day weekend brings everything from festive outfits and green beers to runners lacing up their green shoelaces for a race. A couple of St. Patty’s runs will lead to road closures.

St. Patrick’s Day Dash

A colorful event — featuring costumes ranging from aliens to ballerinas to dinosaurs — will take place this weekend. The 41st annual St. Patrick’s Day Dash will start and finish at the Seattle Center and weave its way through the Amazon corridor and north along State Route 99/Aurora Avenue. All northbound lanes of State Route 99 (SR 99) will close Sunday morning between 6 a.m. and 10:30 a.m.

Drivers will still have access to the SR 99 Downtown Tunnel northbound and will be detoured to Republican Street near the exit. During this time, the SR 99 southbound exit to eastbound Harrison Street will have intermittent closures. Drivers through Seattle should consider using Interstate 5 (I-5) Sunday morning or plan on delays if you plan to use SR 99.

More from MyNorthwest: Summer-long lane reductions return to Eastern Washington’s Vantage Bridge

Kirkland Shamrock Run

Another holiday event, considerably smaller than Seattle’s St. Patrick’s Day Dash but with spirit just as big, is also happening this weekend. During the Kirkland Shamrock Run, hundreds of colorful runners will take to the streets of downtown Kirkland near the waterfront. If you’re heading to Kirkland, plan around the closure of surface streets Saturday morning between 9 a.m. and 12 p.m., or until the last runner crosses the finish line.

There are several Washington State Department of Transportation (WSDOT) projects that will also impact traffic.

Interstate 5 express lanes

The express lanes on I-5 will be closed starting Friday night at 11 p.m. through 4 p.m. Saturday. WSDOT will repair safety barriers that were heavily damaged on Wednesday evening when a car traveling on I-5 south struck the barrier and crossed into the northbound express lanes. Drivers can expect heavy volumes on I-5 during this closure.

More from MyNorthwest: Snow flurries on Snoqualmie cause spinouts and crashes, I-90 shut down overnight

Eastbound Interstate 90

All eastbound lanes of Interstate 90 (I-90) will close across Lake Washington from 10 p.m. Friday to 6 a.m. Saturday. WSDOT crews will conduct regular maintenance inside the Mercer Tunnel and the Mount Baker Tunnel. A number of ramps will also close starting at 8:30 p.m. Friday and will reopen by 6 a.m. Saturday.

• The southbound I-5 on-ramp to eastbound I-90. 
• The northbound and southbound Rainier Avenue South on-ramps to eastbound I-90.  
• The I-90 to West Mercer Way off-ramp.

Interstate 405 south

Drivers between Bellevue and Renton will need to plan alternate routes or expect major delays overnight Saturday beginning at 11 p.m.

Interstate 405 (I-405) south will be reduced to a single lane from 112th Avenue Southeast/Lake Washington Boulevard (Exit 9) to North 30th Street (Exit 6) from 11 p.m. Saturday to 8 a.m. Sunday. The Northeast 44th Street on-ramp to I-405 south will also be closed during this time. 

This is part of the I-405/Renton to Bellevue Widening and Express Toll Lanes Project.  

Nate Connors is a traffic reporter for KIRO Newsradio. Follow him on X. Submit news tips here.

Follow @https://twitter.com/kirotraffic