File:California Fires (MODIS 2019-10-27).jpg

English: Fueled by hot weather, low humidity, and bursts of strong easterly and northeasterly winds, several large wildfires ignited along the West Coast of the United States and Mexico in late October 2019. Seasonal Santa Ana and Diablo winds blew in from hot, dry areas and accelerated down mountain ranges, creating conditions where a few sparks and small brush fires could quickly get whipped up into large conflagrations.

U.S. weather and fire forecasters delivered “red flag warnings” to Californians, predicting extreme fire-promoting conditions through October 29 in various parts of the state. On October 25, forecasts for Northern California called for steady 25 to 45 mile per hour winds and humidity between 9 to 16 percent. In Southern California, temperatures were expected to range from 87 to 97 degrees Fahrenheit (30 to 36 degrees Celsius), with humidity between 2 and 9 percent and winds gusting as high as 65 miles per hour.

On October 25, 2019, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite acquired a true-color image of smoke pouring from the fires, primarily the Kincade fire. The Kincade fire, which first ignited on October 23, raged across remote, steep terrain that was difficult to access. At least 2,000 residents of Geyserville were evacuated, and thousands of people in the region went without electric power due to planned blackouts (intended to prevent electricity-sparked fires). At 9:30 a.m. on October 25, Cal Fire reported that 21,900 acres had burned in the area, 49 structures had been destroyed, and 735 were threatened. The fire was 5 percent contained.

Recent research has shown that fires in California have grown more frequent and larger in recent decades due to rising temperatures. Annual burned area in the state increased by 405 percent from 1972 to 2018.