What is a heatwave? Find out why they happen and how you can protect yourself.
What causes a heatwave? Here’s why they happen and what they can mean for your health.
Although fall is approaching, Californians are not spared from the heat this week.
A heat warning is in effect for parts of Southern California on Tuesday as a heat wave brings rising temperatures to the region through Friday.
But Southern California isn’t the only place dealing with high temperatures this week. Here’s what you need to know to help you stay safe from the heat.
How hot will it be this week?
A heat advisory is in effect for the western San Fernando Valley, including Northridge, Woodland Hills and Van Nuys, through Friday evening. According to the National Weather Service Los Angeles, residents in these areas can expect temperatures between 40 and 45 degrees Celsius during that period, with the highest temperatures occurring on Thursday and Friday.
According to the NWS San Francisco Bay Area, temperatures in northern San Francisco are expected to be between 26 and 29 degrees as the heat advisory remains in effect through the evening. According to NWS Medford, Oregon, Siskiyou County — and its Oregon neighbors — may see temperatures about 11 degrees above normal.
Heat warnings are in place for parts of California through Wednesday as temperatures rise. These areas include:
- In the Sacramento Valley, which includes Stockton, Chico, Redding and Sacramento, temperatures of up to 41.6 degrees Celsius are expected, according to NWS Sacramento.
- According to NWS Eureka, temperatures in Northern Lake and Southern Lake counties could reach as high as 103 degrees.
- According to NWS San Diego, parts of Orange County, including Anaheim, Irvine, Santa Ana and Fullerton, are under extreme heat warnings with highs between 35 and 40 degrees Celsius.
- According to NWS San Diego, extreme heat warnings are in place for the inland valleys of San Diego County, including La Mesa, San Marcos and Escondido, with highs in the triple digits.
Riverside County is also expected to reach triple-digit temperatures by Wednesday, according to City News Service. Dangerously hot temperatures are expected in parts of southwestern California starting Wednesday, including cities in Los Angeles County. Pasadena and Pomona are expected to see highs of 40 degrees, while LA will reach 38 degrees, according to NWS Los Angeles.
National Weather Service map shows where heat poses a threat in California
The National Weather Service’s HeatRisk map shows that most of Southern California, as well as the central and northern parts of the state, are expected to experience moderate heat impacts on Tuesday. Moderate means that most people who are sensitive to heat will be affected, especially if they don’t have a way to cool down or don’t stay hydrated.
Most of California will be in moderate heat through Wednesday, but some areas are considered particularly vulnerable to heat or to people who do not stay hydrated or have no way to cool down. These include Fresno, San Jose, Sacramento, parts of the Inland Empire and cities near San Diego.
Some of California’s highest temperatures will be in the state’s deserts. Palm Springs will see highs of 46 degrees Thursday, seven degrees shy of the July record high. Thermal, north of the Salton Sea, will see highs of 46 degrees the same day, according to the NWS San Diego.
On Thursday, most of Southern California will move into the “severe heat” category, while some parts of the state, including areas near the southern border, Riverside, Avenal and west of Concord, are considered extreme. The NWS describes “extreme,” the highest category on the list, as “rare and/or prolonged extreme heat” that brings little to no overnight relief and will affect anyone who is not properly hydrated or has no way to cool off.
In most parts of California, heat-related impacts are downgraded to moderate to minor through Saturday.
How can I protect myself in extreme heat?
Californians facing high temperatures in the coming days should take precautions to prevent heat-related illness. Some tips from the National Weather Service:
- Avoid strenuous outdoor activities until the coolest time of day
- Wear light, loose-fitting and bright clothing
- Drink plenty of water, even if you are not thirsty
- Spend time in air-conditioned places
- Take a cool bath or shower
- If the room temperature is above 90 degrees, you should not use a fan that blows air directly at you. The dry air will cause dehydration faster.
Symptoms of heat stroke
Heat stroke is the “most severe form of heat injury,” according to the Mayo Clinic, and is caused by the body overheating. This is usually the result of staying in high temperatures for too long.
People with heat stroke should seek immediate medical attention because it can cause heart, brain, kidney and muscle damage. If treatment is delayed, heat stroke can result in “serious complications or death.” While waiting for emergency treatment, people with heat stroke should go indoors or into the shade, remove excess clothing and try to cool down. Some ways to cool down include taking a cold shower, spraying yourself with a garden hose and applying ice packs or cold towels to the head, neck, armpits and groin.
According to the Mayo Clinic, the signs and symptoms of heat stroke include:
- The main sign is a body temperature of 104 degrees or more on a rectal thermometer.
- Altered mental state or behavior
- The skin feels hot and dry due to hot weather, or the skin feels dry or slightly moist due to physical exertion.
- Nausea and vomiting
- Reddened skin
- Rapid breathing
- Racing pulse
- Headache
When does it start to cool down?
Californians seeking relief from high temperatures should not put too much hope in the fall.
Above-average temperatures are expected in California for this time of year. Southern California and the western part of the state are expected to have above-average temperatures in September, according to the National Weather Service’s monthly forecasts, although parts of Northern and Central California have an equal chance of either above-average or below-average temperatures this month.
Paris Barraza is a trends reporter covering California for The Desert Sun. Reach her at [email protected]. Follow her on Twitter at @ParisBarraza.
