Heavy rains are causing significant problems across the Portland area, including light rail delays and traffic tie-ups.

The first of an increasingly wet parade of soaking storms is pummeling northwest Oregon and southwest Washington. Forecasters say the series will likely send several coastal rivers to or above flood stage. Gusty winds and high surf will hammer the Oregon coast.

Key things to know before you go:

Numerous roads throughout the area are closed, and traffic is backed up on most freeways. Check below for closures of main thoroughfares.

The MAX light-rail system and TriMet buses are experiencing significant delays and/or closures. Check the

A successive wave of storms

Here are the latest developments:

11:15 p.m.: TriMet says the MAX Blue Line will remain disrupted Tuesday morning because of a sinkhole in Gresham, but shuttle buses will serve stations between Ruby Junction/E 197th and Cleveland until the issue is resolved.

5:20 p.m.: Northwest Cornelius Pass has reopened between Highway 30 and Northwest Skyline Boulevard after Multnomah County crews cleared a landslide on the road.

Meanwhile, TriMet announced numerous bus lines have been impacted by weather. These lines, which serve commuters throughout Portland, will either not provide any service or will be rerouted until road conditions improve. Visit trimet.org/alerts for more information.

In Vancouver, city crews responded to more than 70 weather-related calls. Roads were also closed during the heaviest rainfall period. The city has set up two emergency, self-serve sites for residents to pick up sandbags. Residents are advised to bring their own shovels to fill bags and be prepared to transport them. The locations for sand and bags are:

In front of fence, near the sign at the former Golden Skate site, 4915 E. Fourth Plain Blvd.

Near the driveway access at Vancouver Public Works' East Operations site, 912 N.E. 192nd Ave.

4:10 p.m.: Portland city officials said emergency crews are working around the clock, bracing for more rain through Wednesday, which could trigger more rockslides, mudslides and road closures.

Maggie Skenderian, Johnson Creek Watershed manager for the city's Bureau of Environmental Services, said Johnson Creek already is approaching the all-time high-water mark.

"We're nearing record flows," Skenderian said at a news conference held at Southeast Portland's Zenger Farm.

9:41 a.m.: Flooding in the Pearl District has stopped the Portland Streetcar at Northwest 10th Avenue and Hoyt Street. One block to the west, brown water is gushing out of a manhole. Hoyt is closed between 12th and 9th avenues:

It's a gusher! Northwest 11th at Hoyt #PDXTST A video posted by Stuart Tomlinson (@stubobusa) on Dec 7, 2015 at 9:53am PST

9:35 a.m.: Sewage overflowed into the Willamette River.

9:30 a.m.: The Oregon Zoo will be closed until noon because of flooding on visitor pathways.

8:39 a.m.: Landslides have closed Northwest Cornell Road in Portland.

8:30 a.m.: The Goose Hollow neighborhood experiences heavy flooding:

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-- Andre Meunier