Late rainfall contributed to what the Obama administration said Monday would likely be a dicey wildfire season in the western United States this year.

Agriculture Secretary Tom Vilsack and Interior Secretary Sally Jewell toured the nation's wildfire command center in Idaho Monday at the same time new satellite imagery warned that fire conditions in Southern California were particularly dangerous this year.

"We are working together to preposition our firefighting teams and equipment to make the most effective use of available resources during this time of constrained budgets," said Vilsack, whose agency oversees the National Forest Service.

The Agriculture and Interior departments said in a joint written statement that analysts had concluded much of the West was in for an above-average summer for fires. Virtually all of California, Arizona, New Mexico, Oregon and Idaho were considered to be in the danger zone.

Winter rainfall is often the key to the severity of the summer and early-fall fire season, and a new satellite analysis released Monday by the Jet Propulsion Laboratory concluded the timing of late winter rains would actually contribute to a potentially bad fire season in Southern California.

JPL scientists said in a written statement the heaviest rainfall fell in late winter, which spurred a growth spurt of brush just in time for the hot, dry summer to kick in and quickly turn the lush vegetation to dry kindling.

"This timing enhanced vegetation growth early this year, particularly in Ventura County, supplying significant new fire fuel even though this was one of the driest overall rainfall seasons on record," laboratory scientist Son Nghiem said. "Had the rains fallen earlier, when the vegetation was in a dormant state, the effects would have been minimal."

Nghiem was the project leader for the laboratory's analysis of satellite measurements of vegetation stress and soil moisture in mountain areas that are difficult to access on foot.