WASHINGTON— The Washington State Department of Transportation (WSDOT) is warning motorists of numerous significant closures in Western Washington this weekend.

“The closures could be a monster for motorists if they do not prepare and plan for their weekend trips in the area,” WSDOT said.

Anyone traveling on State Route (SR) 520 across Lake Washington, on Interstate 405 north, on SR 167 south or on I-5 through the Tacoma, Fife and Federal Way areas should do so this weekend starting Friday evening expect significant closures, September 27th.

West Exit 520 to Montlake Blvd. and Lake Washington Blvd. is closed every evening from Monday, September 23rd to Thursday, September 26th from 10:00 p.m. to 6:00 a.m.

Below is a guide to the upcoming closures, scheduled to begin September 27th:

The SR 520 floating bridge and SR 520 Trail will be closed in both directions between I-5 in Seattle and 92nd Ave NE from 11:00 p.m. Friday to 5:00 a.m. Monday. WSDOT will work on lighting and fire suppression systems under the new Montlake cap over SR 520.

Both directions of Interstate 5 between SR 18 in Federal Way and 54th Ave E in Fife will be closed overnight on Friday, September 27th and Saturday, September 28th.

WSDOT said northbound lanes will close at 10:30 p.m. and southbound lanes will close at 11 p.m. Lanes will open at 7 a.m. on Saturday and fully reopen at 11 a.m., and lanes will reopen at 8 a.m. on Sunday and are expected to be fully reopened by noon.

The WSDOT said the Mercer Street ramps to northbound and southbound I-5 will also be closed this weekend between 10 p.m. Friday and 5 a.m. Monday.

I-405 northbound will be closed from North Southport Drive/Sunset Boulevard Northeast (Exit 5) to Coal Creek Parkway Southeast beginning at 11 p.m. Friday, Sept. 27 and 4 a.m. Monday, Sept. 30.

The following entrances and exits will also be closed:

• Sunset Boulevard northeast on-ramp to I-405 northbound
• On- and off-ramps to Northeast 30th Street (Exit 6)
• On- and off-ramps to Northeast 44th Street (Exit 7)
• On- and off-ramp to Lake Washington Boulevard Southeast (Exit 8)
• Coal Creek Parkway Southeast Exit (Exit 10)

WSDOT said a posted detour will direct people around the closure.

Southbound SR 167 will be closed from SR 516 to South 277th Street in Kent from 11:59 p.m. Friday, Sept. 27, to 4 a.m. Monday, Sept. 30.

The following entrances and exits will also be closed:

• SR 516 ramp
• South 277th Street exit

WSDOT said a posted detour will direct people around the closure.

Stay ahead of traffic by using this information and real-time travel data via WSDOT here.