Dozens of wildfires are burning across California, many caused by lightning during a rare thunderstorm passage on Monday, and exacerbated by ongoing gusty winds and extreme heat. The most active fires are burning in the Bay Area, prompting evacuations, and forcing a State of Emergency in California.
Current Fire Activity
- There are currently 68 large fire incidents that are being actively managed across the US; which is in stark contrast to only 12 large fire incidents one week ago.
- Over half a million acres have burned, and 15,000 wildland firefighters and support personnel are battling fires across the country.
- The California wildfire activity is primarily a result of a severe thunderstorm that moved through the Bay Area region on Monday morning, where multiple lightning strikes caused spot fires to start burning. Many of the current fires are actually complexes of multiple fires that started near each other during the passage of the storms: There are nearly 4,000 structures immediately threatened in the proximity of these fires, and multiple mandatory evacuations in place.
- The LNU Lightning Complex fire in Sonoma and Napa Counties in California is 32,025 acres and 0% contained. This includes the Hennessey and Gamble Fires. This fire grew quickly overnight into the community of Vacaville where several structures were destroyed and thousands remain threatened.
- The SCU Lightning Complex fire in Santa Clara, Alameda, Contra Costa, San Joaquin and Stanislaus Counties grew from 35,000 acres to 85,000 acres overnight and is only 5% contained. No structures have been lost, however many are threatened.
- The CZU August Lightning Complex fire in San Mateo and Santa Cruz Counties is 7,500 acres and currently 0% contained. More than 22,000 people have been ordered to evacuate.
- These fires are burning in areas that are very conducive to wildfire, as indicated by the reds (very high) and pinks (extreme) in the map below of the Guy Carpenter Wildfire Risk Score.
- Additionally, large and damaging wildfires are burning in Colorado, in response to recent emerging and intensifying drought conditions, as well as much above average summer temperatures.
- The Pine Gulch fire outside of Grand Junction, CO is now 87,770 acres and is the third largest fire in Colorado history. There was significant growth on the western flank of the fire overnight.
- The Grizzly Creek fire is now 27,269 acres and Interstate 70 continues to be closed for the second week in a row.
- These fires are all occurring on a backdrop of excessive heat, with temperatures in the western US as much as 10 to 12 degrees above already high summer averages.
- Excessive heat warnings are in place for most of central and southern CA, including the Bay Area where fire activity is high.
- Red Flag Warnings are in place for portions of the Rocky Mountains and Great Basin, where elevated risk exists for fire ignition and spread, as well as extreme fire behavior in already active fires.
- Air quality alerts exist in the Front Range of Colorado, where smoke from fires in the mountains is causing health risks for many large communities.
Guy Carpenter Wildfire Specialists and Meteorologists will continue to monitor fire activity and provide updates as necessary.
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