PORTLAND — The National Weather Service on Thursday, March 9, declared an end to a La Nina that lacked the punch to relieve drought in Oregon or build a spring-proof snowpack in Washington.

The Pacific Ocean along the equator has warmed to normal, returning weather-influencing atmospheric patterns to a “neutral” state, the service’s Climate Prediction Center reported.

Neutral conditions are forecast to last until the early summer. After that, forecasters see the odds tilting toward warm seas and an El Nino, associated with warm and dry Northwest winters.

The climate center cautioned that predictions this far from next winter are far from certain.

For the past three winters, the ocean has been cooler than normal, triggering La Ninas linked to cool and wet weather in the northern tier of the U.S. 

The latest La Nina never developed into a strong one, and it didn’t help Oregon’s drought. In the past three months, the percentage of the state in drought increased to 78% from 56%, according to the U.S. Drought Monitor.

“It’s something we did not expect at all,” Oregon State Climatologist Larry O’Neill said.

Drought conditions in California and Washington improved. O’Neill said Oregon was stuck in the middle, as storms tracked to the south and north.

“I think we had some very bad luck. A lot of storms just missed us,” he said. “Oregon has really missed out on atmospheric-river events.”

La Nina influences the weather worldwide, and Washington irrigators are customarily among the beneficiaries. Washington’s snowpack is 98% of normal.

The near-average snowpack may be deceiving, Natural Resources Conservation Service snow supply specialist Scott Pattee said.

Rainfall has been below normal since the start of the water year, Oct. 1. The ground may suck up melting snow “like a big straw,” he said.

“Even if the snowpack is 100%, it doesn’t mean you’re going to see 100% runoff,” Pattee said.

Washington’s meteorological winter, December through February, was the 32nd driest in 128 years of record keeping.

“La Nina is an influencer, but not an absolute determinant of what happens,” Washington State Climatologist Nick Bond said. “Our snowpack is fine. It’s not quite as healthy as I thought it would be.”

The Bureau of Reclamation issued its first summer water forecast March 9 for the Yakima River basin. Irrigators subject to curtailment will get 86% of full allotments, the bureau predicted.

Snowpacks that melt into the basin’s reservoirs are near normal, but rain that falls into the reservoirs has been below normal. Reservoirs held 81.5% as much water as normal.

Irrigators could still get 100%, depending on the weather in the next several weeks, according to the bureau. On the other hand, allotments could be as low as 62%, the bureau projected.

“I think we can go either way at this point,” Bureau of Reclamation hydrologist Chris Lynch said.

The National Weather Service will issue its spring outlook March 16. Bond said he expects La Nina’s influence to last for awhile.

“It’s not like turning a switch. There’s probably some kind of lingering effects,” he said. “So far it’s playing out like we’ve seen in past La Ninas with the end of the winter on the cool side.”

California’s winter was its 11th wettest on record. Storms dropped 32 trillion gallons of snow and rain in January alone, according to the National Centers for Environmental Information.

Idaho had its 40th coolest and 39th driest winter. Some 97% of the state is in drought or abnormally dry, the same percentage as three months ago, according to the Drought Monitor.