The heat dome settling in over California will bring record temperatures this holiday weekend and beyond. The National Weather Service has issued an Excessive Heat Warning for most of the state, with triple digit daytime temperatures and 70’s to mid-80’s overnight lows in the Foothills. The long duration heat impacts will linger at least until Tuesday, possibly longer. We’ve compiled tips and resources for you to help you stay as cool and safe as possible.

NWS outlook

Bill Rausch with the National Weather Service in Sacramento spoke at the Cal OES briefing today. “We are looking at a high confidence, extreme heat event covering a large part of California. The heat is already building in Southern California and that’s going to be pushing north and by this weekend and into early next week, it’s going to cover a majority of California. It’s an extreme heat event because of a couple of reasons. The temperatures themselves are ten to 20 degrees above normal in the daytime. Also, the recoveries at nighttime are going to be very unseasonable. We all know that’s the time for the body to recover and that won’t be happening. Also, there will be a chance of all time and monthly record highs. We don’t expect a large area of that, but several stations have a chance of hitting all time record highs, which of course is not good.”

In a separate briefing, the NWS also shared the outlook for very low Relative Humidity (RH) values. Given the excessive heat and the dry fuels, if a fire were to start, it definitely could grow rapidly.

Relative Humidity values for Sunday

Health risk

During a Cal OES briefing today Dr. Tomás Aragón, the State Public Health Officer, emphasized the importance of staying cool, hydrated and informed. “With respect to heat related illness the people who are the most vulnerable are the very young, the very old, and people who have chronic medical conditions especially if they’re taking a medication that may make it more difficult for them to regulate their temperatures.” He added, “people who are homebound, people who are homeless, and also certain occupational settings where they may not have good air conditioning. An important thing for everyone is to please check in on your neighbor and check in on your coworkers.”

“Many places do not have air conditioning. So it’s important for those areas to really remind people, even though normally the temperature here is not high, when you do have a heat wave, you have to be that much more careful. Other things for folks to think about is cars. Don’t leave kids and pets in cars, really critical,” Aragón continued.

Recreation and events

Aragón talked about risks associated with outdoor events or recreation, from a health perspective: “You may have a sporting event where you have tens of thousands of people who are outdoors baking in the sun. Across the state, people who are running special events really need to think through carefully and have a plan on how they are going to manage the people who are attending their special events. What happens with heat waves? People can really decompensate pretty quickly, especially if they’re drinking alcohol and they’re having direct access to sunlight. People can get pretty sick. Oftentimes people talk about things like heat stroke when your body is unable to regulate temperatures, usually when the temperature is above 103 Fahrenheit and people will start having changes in mental status they will become confused, impacting their judgment. They don’t realize that they’re getting themselves in trouble and that’s a real problem, especially if they’re by themselves. They might be out hiking. We know situations where people are out hiking and this happens and they don’t know that they’re getting in trouble. And of course heated exhaustion.”

  • Limit your alcohol intake, instead drink plenty of water.
  • If you are planning on hiking or biking, consider shortening the distance or even postponing your hike.
  • Walk your pets in the early morning when temperatures are coolest. Asphalt and even bare dirt heats up rapidly and can cause damage to your pet’s paws.
  • If you are recreating on public lands, please obey all fire restrictions. Any fire starting has potential to rapidly grow into a major incident.
  • Hydrate.


  • Adequate hydration is of utmost importance. Take breaks from any activity and hydrate.
  • Make sure your pets have fresh water
  • If you can, put water dishes out for birds and critters. Be mindful of keeping the water clean.
  • Hydrate.

Prepare for power outages

With Enhanced Power Safety Settings (EPSS), powerlines in your area shut off instantly when struck by a branch or object. To reduce potential ignitions, lines stay off until they’re fully inspected and safe to energize.

  • In rural areas, power outages affect wells if no generator is installed.
  • Get some cash in case stores cannot process your bank cards due to a power outage.
  • Hydrate.

Car safety

  • Keep the car’s gas tank full, in case of a fire you want to be ready to evacuate.
  • Don’t park in high grass, catalytic converters get extremely hot.
  • If you are towing a boat or trailer, avoid dragging chains that can start a fire. Inspect the brake lights and turn signals on the trailer.
  • Hydrate.

Know your Zone and make it a No Spark Zone

  • In case of an emergency, your Zone may be placed under an evacuation warning, order or you might be asked to shelter in place. Find your Zone for Nevada County here.
  • Now is not the time to use equipment that can start fires. Mowing in triple-digit heat is not only detrimental to your health, it can start a fire faster than you can say “Oops.”
  • If you are a BBQ fan, have a safe and clear space around your cooking zone.
  • Hydrate.

Staying cool

  • Counties and cities will open cooling center and we’ll add these to the list.
  • Local businesses will be glad to let you cool off while you shop, a win-win for all.
  • If you are lucky enough to have a/c, pre-cool your home in the early morning. As the temperature rises outside, raise your thermostat and circulate the pre-cooled air with a fan.
  • Close windows and shades on the sunny side of your home.
  • Avoid using major appliances like stoves, ovens, dishwashers during the heat of the day.
  • Hydrate.

Placer County will keep three of its libraries open throughout the long holiday weekend to help residents stay cool and out of the heat. County libraries located in Auburn, Foresthill and Colfax will extend their hours of operation until 7 p.m. on Saturday. Although typically closed on Sundays and holidays, these three libraries will be open from noon until 7 p.m. on Sunday and Labor Day Monday with air-conditioned spaces but limited library services. 

A list of air-conditioned centers in Roseville is available on the City of Roseville’s website, here.

Statewide list of cooling centers and power outages via Cal OES

Have a tip you’d like to share? Email or text us at 530-409-9888.