El Nino likely will fade away by late spring, but will make the Pacific Northwest unseasonably warm and dry until then, the National Weather Service predicted Thursday.

The outlook for March, April and May offers little hope for improved snowpacks, particularly in Washington, where the snowpack Thursday was 60% of average.

Urban Eberhart, manager of the Kittitas Reclamation District in Central Washington, said he expects farmers will have water supplies trimmed. “Anything can happen from here on out, but it will take a lot to pull us out of it.”

El Nino continues to dominate seasonal forecasts by the weather service’s Climate Prediction Center. Because of El Nino, the weather service predicts the northern U.S. will have a mild spring.

The chances for above-normal temperatures are highest in Washington and Oregon, where El Nino’s influence is the strongest. Above-average temperatures are expected to extend into Idaho and Northern California.

Washington, the Idaho Panhandle and most of Oregon also are expected to be drier than normal for the three months.

Oregon’s snowpack was 91% of average and California’s was 85% of normal Thursday. In Idaho, the snowpack was 60% north of Salmon River and 91% to the south.

Reservoirs low

The Bureau of Reclamation’s five Yakima River basin reservoirs Thursday held 62% of their usual volume for the date. The bureau will make its first water-supply forecast March 4. Farmers with junior water rights are subject to cutbacks.

Roza Irrigation District manager Scott Revell said the district has been telling irrigators “there are not good omens out there.” The district has been through mild droughts recently, but not a severe drought since 2015, when irrigators received 47% of their full allotments.

Since then, the district and farmers have invested in water-saving projects, such as replacing canals with pipes and sprinklers with drip lines, Revell said. The district typically uses 80% of the water it’s entitled to, he said.

The Kittitas Reclamation District will install 11,843 feet of new pipes or canal liners this winter to conserve water, Eberhart said. If the district gets 75% of its full water allotment, “we can kind of get by. Once it drops below that, things get real difficult,” said.

La Nina in forecast

Higher sea surface temperatures in the Pacific Ocean trigger an El Nino. This winter, the seas were warm enough to trigger the first strong El Nino since the winter of 2015-16.

Below-surface waters are starting to cool and signal that the sea surface will cool soon, too. By late spring, the ocean temperature probably will be near normal, according to the weather service.

Historically, a La Nina follows an El Nino, and the weather service expects that will be the case this time. A La Nina is likely to develop by late summer or early fall, the weather service predicted.

Northwest winters are typically colder and wetter during La Nina, the opposite of El Nino.

The cold spell in January was atypical for an El Nino. More typical was December, which was the third-warmest in Washington’s history, according to records dating back to 1895.

The Washington Department of Ecology declared a drought emergency in 12 watersheds last year. The declaration is in effect until June 30.

The department’s Water Supply Availability Committee was to meet Feb. 28 to review conditions around the state.