By TIM HEARDEN
SACRAMENTO -- Much of interior California is embarking on a stretch of triple-digit days that could signal the start of a sweltering summer.
Strong high pressure is building over the region from the eastern Pacific Ocean, bringing temperatures that could be 15 to 20 degrees higher than normal for this time of year, the National Weather Service reports. The result is expected to be highs this weekend of 110 in Sacramento and 112 in Redding.
The heat wave could be just the beginning, as the odds favor a warner-than-normal June in the Sacramento Valley, said Jim Mathews, the NWS' lead forecaster here.
"Could that trend continue in July and August? There certainly is that possibility," Mathews said.
"I think we're looking at persistently hot and dry conditions over the mountain West," he said. "If you look at the (U.S.) Drought Monitor, the really strong drought conditions over the panhandle of Texas, the mountain West and part of the Great Plains indicate that the ridging that's been with us for more or less the past year is going to persist."
The federal Climate Prediction Center envisions warmer-than-normal temperatures for the next three months in most of the Southwest except for the coasts. While the Pacific Northwest is expected to remain drier than usual during that period, California faces equal chances of above- or below-normal precipitation, according to the agency.
The two biggest concerns with a hot summer are water supply and safety for workers, said Tyler Christensen, who grows nuts and plums for prunes near Red Bluff, Calif.
"I think what it does is it will shorten the surface water even further in the midst of our drought," Christensen said. "Crop-wise, we'll probably be pretty good as long as we can keep everything fully irrigated."
Excessive heat can affect the quality of walnuts and prunes -- particularly walnuts, Christensen said. Last summer, a prolonged August heat spell in the Central Valley caused early varieties of almonds to come in lighter than expected, and rangeland and non-irrigated pasture quality continued to deteriorate.
Hot temperatures also cause valencia oranges to re-green, which brings the export season to an end quickly because growers have to treat with an ethylene gas which restores their color, California Citrus Mutual has explained.
A hot summer could worsen drought conditions after a dry spring that has put most communities in the Golden State below their seasonal rainfall totals. As such, growers are dealing with reduced water allotments again this year, although the statewide reservoir storage is at 85 percent of normal for this time of year, according to the California Department of Water Resources.
Willie Thompson, who grows peaches, cherries, apricots and other crops near Yreka, Calif., said his drip irrigation was enough to keep his crops flourishing. He expects his business to be brisk this summer, as some other high-elevation growers were hit with freezes this winter that diminished their crops.
"I think I'm going to be overrun with customers this year," Thompson said as he operated a booth at the Old Lewiston Peddlers' Faire in Lewiston, Calif., on June 1. "There's been some freezes along the West Coast and I survived that. People who didn't survive it are going to be buying from me."
Here are the May and seasonal rainfall totals and comparisons to normal for selected California cities, according to the National Weather Service. Totals are as of May 31:
Redding: Month to date 0.86 inches (normal 1.85 inches); season to date 26.88 inches (normal 33.93 inches)
Eureka: Month to date 1.17 inches (normal 1.78 inches); season to date 31.88 inches (normal 39.58 inches)
Sacramento: Month to date 0.3 inches (normal 0.68 inches); season to date 14.98 inches (normal 18.31 inches)
Modesto: Month to date 0.14 inches (normal 0.63 inches); season to date 9.02 inches (normal 12.99 inches)
Salinas: Month to date 0.01 inches (normal 0.35 inches); season to date 8.93 inches (normal 12.74 inches)
Fresno: Month to date 0.07 inches (normal 0.43 inches); season to date 5.67 inches (normal 11.29 inches)