Maps show how quickly Los Angeles fires engulfed communities

The deadly combination that scientists have long feared is unfolding: strong winds, extremely dry conditions, and open land are working together to push wildfires towards densely populated communities at an alarming rate. This "perfect storm" is wreaking havoc in Los Angeles.

Currently, two devastating fires remain completely out of control, having besieged Los Angeles, the second-most populous city in the United States, for the third consecutive day. So far, the flames have caused at least 10 deaths, incinerated entire neighborhoods, and forced over 180,000 people to flee their homes.

The Palisades fire, located in the western part of the city, is considered the most destructive fire in the city's history, destroying over 1,000 homes in a single day and causing at least two deaths. The most recent Kenneth fire, which broke out on Thursday afternoon in the western part of the city, rapidly expanded 16-fold within three hours.

The following images combine population density data and fire maps to track the speed at which the flames are spreading and which communities are being engulfed as firefighters struggle to control the blazes. The Palisades fire initially broke out in the Santa Monica Mountains at 10:30 am on Tuesday (5:30 am Wednesday AEST). Within 20 minutes, it had expanded from 8 hectares to engulf over 80 hectares in raging flames. By the next night, it had burned approximately 6,400 hectares, equivalent to 2.5 times the area of the city of Sydney.

Approximately 24 hours after the first report of the fire, the Pacific Palisades community, home to more than 20,000 residents, was reduced to ruins. Residents who stayed behind to fight the fire described using buckets filled with water from swimming pools to extinguish flames because the fire hydrants had run dry. The Palisades fire is now considered the most destructive fire in Los Angeles history, with local authorities counting two deaths and approximately 5,000 homes, businesses, or other buildings destroyed so far. Over 37,000 people have been forced to evacuate from surrounding areas. Currently, the fire is still burning within an area of nearly 8,100 hectares, with only 6% of the fire under control.

The Eaton fire, located near Altadena and Pasadena in the northern part of the city, broke out at 6:18 pm local time on Tuesday (1:18 pm Wednesday AEST), expanding to over 400 hectares within six hours. By the next night, the fire area had expanded more than tenfold to 4,300 hectares, with 5 deaths reported. Officials estimate that 5,000 buildings have been destroyed, while over 100,000 people remain under mandatory evacuation orders. Currently, the fire is still burning out of control within an area of over 5,500 hectares. Both the Eaton and Palisades fires are considered among the five most destructive fires in California history.

The Hurst fire, located in the San Fernando Valley northwest of Los Angeles, broke out at 10:30 pm local time on Tuesday (5:30 pm Wednesday AEST). By 2:00 pm local time the next day, it had spread to 200 hectares, triggering mandatory evacuation orders in neighboring Santa Clarita. By 1:34 pm local time on Thursday (8:34 am Friday AEST), it was burning within an area of nearly 350 hectares. As of 8:20 pm on Thursday, the fire area had been reduced to 312 hectares, with 37% of the fire under control.

The Lidia fire, located in Acton, a rural area northeast of the city, broke out at 2:07 pm local time on Wednesday (9:07 am Thursday AEST), spreading to over 140 hectares by the evening. As of 10:00 pm local time on Thursday (5:00 pm Friday AEST), the fire area had expanded to nearly 160 hectares, but 75% of the fire was under control. The Sunset fire, the most recently reported fire, broke out near the Hollywood Hills at 6:00 pm local time on Wednesday (1:00 am Thursday AEST). By the time mandatory evacuation orders were issued that night, the fire had spread to approximately 8 hectares and was threatening affluent areas along Hollywood Boulevard and Mulholland Drive. After firefighters made significant progress overnight, evacuation orders were lifted for most areas the next morning. According to local authorities, the fire reached 20 hectares at its peak and is now completely under control.

The most recent Kenneth fire broke out in the Calabasas and Hidden Hills areas in the western part of the city at 3:30 pm on Thursday (10:30 am Friday AEST). In less than three hours, the area covered by the fire expanded 16-fold, from 20 hectares to 320 hectares. Currently, the fire is completely out of control, having spread to nearly 390 hectares by Thursday evening. Mandatory evacuation orders have been issued for the surrounding areas.

Just days ago, the National Weather Service in Los Angeles warned of an extremely high fire risk during a "life-threatening and destructive" storm. The city, surrounded by mountains to the north and bordering the ocean to the south, has long been aware of the wildfire risk posed by the Santa Ana winds, which are generated by the region's geological structure. These storms are caused by strong winds surging from the Mojave Desert, which accelerate as they pass through "wind tunnels" formed by gaps in the mountains north of the city. Over the past few days, hot, dry air pouring down from the mountains and across the city has fueled gusts of over 145 km/h and wind speeds approaching 100 km/h. These winds—expected to be strongest from Thursday afternoon to Friday morning (Friday to Saturday morning AEST)—have propelled the fires at an alarming rate.

John Abatzoglou, a climatologist at the University of California, Merced, told The Washington Post that the combination of an unusually strong Santa Ana storm with one of the warmest summers on record has created "the roots of a disaster." He said, "If the region had received close to normal rainfall this fall and winter, we would not be facing these fires."