The US wildfire season experienced below-average fire activity this year after abundant spring moisture and below-average temperatures across western states, although large fire potential is expected to persist in California until December.

A report from reinsurance broker Guy Carpenter says the number of fires so far this year is less than any other year in the past decade excluding 2013, and the area burned is “on par with the average”.

That is a significant change from the past two years when wildfires ravaged California, sparked by long-running drought and conditions caused by climate change.

Wildfire season peaks in August and ends in September for the majority of North America, although in California seasonal Santa Ana winds can influence fire into autumn.

California’s Camp wildfire in November 2018 was the single largest insurance loss event last year at $US12 billion ($17.8 billion), according to Swiss Re. It burned more than 62,000 hectares and destroyed at least 18,700 structures, and smoke caused widespread air pollution throughout the San Francisco Bay Area.

Most weather models agree there will be average to slightly above-average Santa Ana wind activity this season. August and September were abnormally dry in California.

“Despite the wet spring and early summer, finer fuels have dried out in late summer and are quite receptive to fire across most of the state,” Guy Carpenter says. “It should be stressed that significant wildfires may still occur in regions forecast for normal or below normal potential.”

The combined precipitation and temperature outlook moving into October indicates an increasing, although not extreme, risk for fall season wildfire for California, it says.

There are three large uncontained fires burning in the US, although none are immediately threatening structures. Lightning fires across the Great Basin in Nevada and in the northern Rockies, which struck in mid-September, are still burning.