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Here’s what the water supply outlook says about Oregon’s precipitation

A downed tree on an icy road amid the winter storm in Portland, Oregon on Thursday, December 22, 2022. (Courtesy: Oregon Department of Transportation)

Editor’s note: A previous version of this story had a typo in a county name. It has since been corrected.

PORTLAND, Ore. (KOIN) — The National Resources Conservation Service has released the first Oregon Water Supply Outlook of 2023, which details the state’s water and snow levels every month from January to June.

The latest outlook reveals how last year’s La Niña cycle, warm October and early-season storms have affected conditions in Oregon.

According to the U.S. Department of Agriculture, the “water year” starts on Oct. 1 and lasts until Sept. 30 of the next year. The beginning of water year 2023 was atypical for Oregon, and KOIN 6 News reported on the month’s warm streak.

The NRCS indicated that the dry October did no favors for the state.

“At the start of the water year, nearly 69% of Oregon was in some category of drought (D1-D4) with nearly 31% of the state in extreme to exceptional drought (D3-D4),” NRCS said in the outlook. “At the start of January, drought conditions have improved slightly with nearly 60% of the state in some drought category. About 26% of Oregon is in extreme to exceptional drought, with persistent exceptional drought in Crook County.”

November brought on more storms for Oregonians, but the outlook shows that there was a higher proportion of snow precipitation than rain — which caused below-average water supply basins outside of northeastern Oregon and the Owyhee Basin.

However, precipitation levels increased in December. Many sites where snow measurements were collected showed that the season’s atmospheric river events led to above-normal snowpack conditions across the state and slightly helped the precipitation deficit.

“Towards the end of December, several SNOTEL sites, notably in the Cascades and in southern Oregon, experienced a rain-on-snow-event and melting of some early season snowpack from a large atmospheric river event that brought highly variable temperatures. The same event also contributed additional snow accumulation,” NRCS said.

The service reported that all Oregon basins were above or well above normal snowpack as of the new year. Also as of Jan. 1, water-year precipitation in northeastern Oregon fell to near normal while rising to well-above normal in the southern region.

According to NRCS’s 8-14 day outlook, many Oregon residents can anticipate above-normal precipitation and temperature potentially lasting until Wednesday, Jan. 18.