The parade of atmospheric rivers that pummeled California last month left behind widespread devastation — and the potential for a more dangerous 2023 fire season, The Guardian reports. Climate change, mainly caused by the extraction and combustion of fossil fuels, is warming the atmosphere, allowing it to hold (and then dump) more moisture and precipitation in the form of catastrophic storms.

Beyond the more than 22 people left dead in their wake, the storms also toppled trees, leaving high-quality ignition opportunities littered up and down mountainsides. Those downed trees and landslides also made sections of road impassible, blocking fire prevention equipment from getting to where it needed to be. The heavy precipitation interrupted or prevented planned burns, which are a proven tactic to reduce wildfire severity and improve forest health. But the most dangerous fire impact of the storms could actually be the moisture.

As happened in the record-incinerating 2020, extra moisture from the rain and snowpack can increase plant growth, while dry conditions later in the summer could turn all that extra vegetation into tinder-dry fuel. “When that rain comes – and it came last month – that results in significant fuel load increases,” Isaac Sanchez, a CalFire battalion chief, told The Guardian. “[Plants] are going to grow, they are going to die, and then they are going to become flammable fuel as the year grinds on.”

“That is now the reality of the environment in the state that we live in,” Sanchez, added. “We are constantly facing a double-edged sword.” (The Guardian; Climate signals background: 2020 Western Wildfire Season)