FELTON (CBS SF) — Drought conditions across the San Francisco Bay Area was setting the scene for an early wildfire season, officials said.

Cal Fire crews assigned to the San Mateo-Santa Cruz unit have responded to and suppressed five wildland fires since March 31.

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“This is highly unusual for this time of year,” Cal Fire said in a news release. “Because of dryer and warmer conditions, coupled with a second year of drought, fuels are apt to burn. Rainfall totals are 50% of normal for this time of year for the region.”

According to the U.S. Drought Monitor, conditions range from moderate to extreme drought across the San Francisco Bay Area. Rainfall totals from the wettest part of the year were 50 percent or more below normal.

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Last year, the Cal Fire CZU crews were involved in a historic wildfire battle across the region. Wildfires burned more than two million acres in 2020 in Northern California — 3,125 square miles — nearly three times the size of Chicago, Manhattan and Los Angeles combined.

Wildfires burned thousands of homes, claimed dozens of lives and charred woodlands, forests and wine country vineyards, leaving an ugly scare visible from space.

Among the major blazes was the CZU Lightning Complex fires that were sparked by an intense dry lightning storm that ignited fires in San Mateo and Santa Cruz counties. By the time the flames were brought under control, 86,509 acres were burned, thousands of homes destroyed and one life taken.

One of the recent fires was a 6-acre blaze within the CZU Lightning Complex burn area. It was the result of a
“sleeper spot” which can include tree stumps and roots.

“Even months later, dry conditions and wind can fan these sleeper spots, which can come back to the surface and ignite surrounding vegetation,” Cal fire said. “We will continue to monitor, respond to, and suppress these smokes as they arise.”

Cal Fire officials said several of the other recent fires were the result of escaped burn piles, including one burn pile of household trash.

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“This is shaping up to be a potentially significant wildfire year,” Cal Fire officials warned. “Please be alert to the conditions around you, and report anything suspicious.”