Fueled by two weeks of erratic Santa Ana winds, the Thomas Fire exploded late last year, wreaking destruction across more than 400 square miles (1,000 square kilome- ters) of two coastal counties in Southern California. It would be 40 days before it was officially declared 100 percent con- tained. MSAVI Photography On Dec. 2, 2017, the U.S. National Weather Service (NWS) issued an alarming statement alongside a “red flag” warning, as it forecast an unusually strong Santa Ana wind event that would affect a large portion of Southern California’s inland and coastal regions. The NWS predicted sustained winds of 20 to 40 m.p.h. (32 to 65 km/h), with the potential for gusts in some areas above 70 m.p.h. (110 km/h) — along with bone-dry humidity. “This will likely be the strongest and longest duration Santa Ana wind event we have seen so far this season,” the statement cautioned. “If fire ignition occurs, there will be the potential for very rapid fire spread and extreme fire behavior.” Within 48 hours, a small brush fire of unknown origin ignited in a rugged canyon north of Santa Paula, 12 miles (19 kilometers) east of the coastal town of Ventura. It was the start of what would become known as the Thomas Fire — an event so devastating in its size that it eclipsed all other fires in an already record-breaking California wildfire season and became the largest in the state’s modern history. Powered by winds gusting to an estimated 60 m.p.h. (95 km/h), the flames spread from the fire’s origin as quickly as the NWS’s forecast had warned was possible, allowing the fire to explode in size as it fed on Southern California’s tinder-dry vegetation. 56 Vertical magazine Taking on the Thomas Fire In early December, an embattled California saw another major fire at the end of what had already been a record-breaking wildfire season. Fueled by an unusually strong Santa Ana wind and tinder-dry vegetation, the Thomas Fire quickly grew to become the largest in California’s modern-day history, presenting a unique challenge to the aerial firefighting community. By Dan Megna