Landslides are also a danger, and one took place Thursday at the west end of the St. Johns Bridge.

COURTESY PHOTO: ODOT - The landslide that closed I-84 between mileposts 36 and 37.The National Weather Service has issued a flood watch for northwest Oregon and southwest Washington through Friday, Jan. 7.

Heavy rains are forecast from Salem to Vancouver that could trigger widespread flooding.

"Some of the vulnerable rivers around the region are likely to reach flood levels. Low-lying spots that are also open to flooding may have issues through this event as well. You will want to watch out for the massive puddles and water-covered roadways when you're heading out," KOIN 6 News Meteorologist Joseph Dames reported on Thursday, Jan. 6.

The Pudding River near Canby is one of the trouble spots were minor flooding has already occurred.

"With the soils as saturated as they already are, and also the likelihood of some snow melting from lower elevations, all of that is going to combine for the threat of flooding," Andy Bryant, a hydrologist with the National Weather Service, explained.

Bryant told KOIN 6 News that Wednesday and Thursday will bring a one-two punch of snow melt and rain.

"We don't see this being a historic flood, but it's definitely going to affect multiple rivers. This is another weather hazard, and for the folks who this impacts, this will be pretty serious," Bryant said.

COURTESY GRAPHIC: KOIN 6 NEWS - Heavy rais are forcast for the region through Friday in this KOIN 6 News projection.Landslides are also a threat. Northwest Bridge Avenue was closed in both directions at the west end of the St. Johns Bridge early Thursday morning by a landslide, Portland Fire & Rescue said.

And a landslide closed all eastbound lanes of Interstate 84 near Cascade Locks early Thursday morning, according to the Oregon Department of Transportation. The freeway was closed from Troutdale to Hood River while the slide was cleared. Icy conditions, downed trees and powerlines are also creating road hazards in Hood River County.

U.S. 26 is currently open as an alternate route between Central Oregon and the Portland area.

Multiple crashes on rain-slickened roads were also reported Thursday morning, Jan. 4. They include a semi-truck that reportedly jack-knifed and leaking fuel, blocking the road near milepost 53 on I-84, which ODOT said is complicating the reopening efforts.

KOIN 6 News is a news partner of the Portland Tribune and contributed to this story.

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