On the heels of devastating wildfires that killed more than 40 people in Northern California earlier this month, Southern California is now on high alert for fire danger.

Nearly all of Southern California has been placed on a red flag warning through Wednesday, as weather conditions ― including high winds, low humidity and record-breaking heat ― make the region particularly susceptible to wildfires.

As temperatures reached record highs above 100 degrees in Los Angeles and nearby counties on Monday, and were expected to rise even further in the coming days, the National Weather Service warned of the “most dangerous fire weather conditions seen in the past few years.”

Cal Fire has increased staffing in the area, bracing for any fires that might come. The agency has also been pushing out an important message to the public: You can help prevent a wildfire, too.

“About 95 percent of wildfires have a human cause,” Cal Fire Battalion Chief Mike Mohler told HuffPost. “Our releases remind the public to be vigilant. Prevention and education is half the battle.”

Both Cal Fire and the National Weather Service tweeted a list of activities people should avoid during high risk weather.

Some actions people should not take are fairly obvious: Avoid campfires and burning yard debris. But some high-risk activities may be more surprising, particularly to folks who don’t live in traditionally high-risk fire areas. For example, people shouldn’t mow lawns after 10 a.m, Cal Fire said.

Equipment use is one of the top causes of wildland fires, Mohler told HuffPost. Sparks can come from activities as seemingly innocuous as towing a trailer through brush, since any chains dragging could throw sparks, or driving a vehicle over dry grass, as hot exhaust pipes can start fires.

Some other common activities dangerous in red flag conditions include shooting firearms and discarding cigarette butts, a spokeswoman for San Diego County warned.

Cal Fire’s website also told families to have an action plan in case of a wildfire, including knowing where to evacuate to and what to take out of a house.

“We want to send the message home that now is not a good day to be mowing your weeds,” Cal Fire public information officer Kendall Bortisser told HuffPost. “You should start thinking about evacuation planning: How are you going to get out? What are you gonna take with you? How are you going to reach family? We’ve learned over the years that fire is prone to burn anywhere.”

The fire warnings in Southern California come just after the deadliest wildfires in the state’s history hit Northern California, killing dozens of people, destroying thousands of homes and causing more than 100,000 residents to evacuate.

• This article originally appeared on HuffPost.