BOISE — The Western wildfire season could start late at middle and high elevations thanks to the unusually wet winter, but forecasters say the bigger concerns are rangeland at lower elevations.

“Fire season could be pushed back a bit, by a couple weeks” at higher elevations, said Jim Wallmann, U.S. Forest Service meteorologist at the National Interagency Coordination Center.

That would occur if the rest of spring brings conditions close to normal, he said. Trees at middle and high elevations will hold moisture later into the season as a result of the above-normal winter snow and rain.

“The bigger concern is lower elevations,” Wallmann said, referring to the rangeland.

Wet conditions and above-normal soil moisture “contribute to a lot more grass growth,” he said. That will result in “a higher and more continuous fuel bed in the lower elevations in grass and sage.”

Fire risk at low elevations would jump when the fine fuels dry out in late June and early July, said Wallmann.

That occurred to an extent last year in southwest Idaho, following the unusually wet spring. The number of range fires exceeded the year-earlier total, he said.

“Fortunately, none got too big,” Wallmann said.

A transition to El Nino weather, which is associated with drier conditions in the Northwest, is coming more quickly than predicted, he said. How it plays out in the next couple of months will have a major impact on the fire season.

The forecast calls for continued warming through spring and into summer, with dry El Nino conditions “possible, if not likely, by the end of summer,” according to NIFC’s May 1 outlook for large fires.

The report covers May through August.

In the Northwest, fuels remain wet, according to the report. Snowmelt timing will determine how fast the fuels dry.

Meanwhile, forecasts suggest a transition to warmer-than-usual weather during the summer, and fuel curing in areas of tall grass production will increase the potential for fire growth.

An above-average potential for large fires is expected in July and August in central and southeast Oregon.

Drier-than-normal conditions in northern Idaho and northwest Montana could align with expected warming to increase fire potential, though expected May precipitation could reduce this concern, according to NIFC.

In southwest Idaho and northwest Nevada, above-normal carryover fuels and new growth of grass and brush will increase the risk of large fires to above normal by July.

Fire risk will be below normal to normal in June and July in Northern California. Normal large-fire activity is expected in August.

In Southern California, below-normal fire risk is expected through August following the exceptionally wet winter.