PORTLAND, Ore. (KOIN) – We are now starting to see the first stage of our block of wet valley weather, mountain snow, and potential freezing rain for the Gorge.
With the support of water vapor coming from the atmospheric river, we are planning for moments of heavy rain and potential flooding.
The main timing of this event will be Thursday night through the first of the weekend. Moments of heavy rain on Thursday p.m. and then again all day Friday and most of Saturday.
The National Weather Service located in Portland has issued a Flood Watch for the Willamette Valley Thursday from 10 p.m. to Sunday 10 a.m. Locations of the Oregon Coast and also the western sector of the Columbia River Gorge.
Currently, rivers around the region are fairly low. Hydrologist Andy Bryant with the National Weather Service says rivers are currently at fall flow but will increase to winter flow levels during and after this event, which means many rivers will be much higher and potentially at flood levels. Some locations Bryant suggested to keep an eye on are the Siletz and Alsea rivers. You can find the river forecast here. Additionally, local urban and rural flooding is possible.
Here is a 24-hour impact timeline from the coast to areas of The Gorge. Rain started off light Wednesday night and will increase heading into Thursday afternoon and evening. Flooding likely to hold off until late Thursday and into the weekend, but some local areas where drains are still covered may be an issue before then.
Notice that mountain snow will start right away and will continue through most of the event. However, snow levels will increase to about 6,000′ by the time we get to Friday, leading to most of the passes and ski resort bases to just rain.
Lastly, the Upper Hood River Valley may experience a few hours of freezing rain as a warmer air mass takes over. You can read more about that here!
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