A heat wave bringing blazing temperatures to San Diego County is expected to reach its peak Wednesday, sending temperatures up to 20 degrees above average before a cool down begins.
A National Weather Service excessive heat warning for most of the county will remain in effect until 8 p.m. Thursday when a high-pressure system that pushed temperatures into triple digits inland and in the deserts will begin to diminish.
Low-temperature records were broken along the coast Tuesday, including in Oceanside, which was excluded from the current heat warning but was under a heat advisory.
The highest elevations in the mountains were also under a heat advisory through Thursday.
San Diego, Ramona, Campo, Vista and Chula Vista saw record-matching high temperatures Tuesday but no high-temperature records were broken in San Diego County.
That could change on Wednesday as temperatures soar.
"We're going to see these temperatures really climb and reach their peak on Wednesday," NBC 7’s Weathercaster Llarisa Abreu said.
Campo has the potential to beat its current record set in 1943 by five degrees, according to the NWS. Ramona, Chula Vista, El Cajon and Alpine may also break current records.
The California ISO has asked the state's residents to conserve energy while the heat warning is in effect to avoid overtaxing the electricity grid.
The Flex Alert will be in effect from 5 to 9 p.m. Wednesday.
The combination of extreme temperatures and low humidity has the potential to spark and fuel wildfires. The NWS said the region will experience elevated fire weather conditions through Friday, especially in the deserts and low mountains where winds will develop.
The heat can also create dangerous conditions for residents, the NWS warns.
Abreu reminds residents to drink lots of water, remember to not leave children or pets in cars, stay inside as much as possible and limit time outside as heat illnesses are likely during the warning period.
The county's official list of "Cool Zones" for 2018 include community centers, recreational centers, libraries, senior centers and museums.
The heat wave prompted Cleveland National Forest official to shut down two popular hiking trails, Three Sisters and Cedar Creek falls, through Thursday to prevent heat-related injuries.
Residents attempting to escape the heat at San Diego County beaches may be met with high surf and strong rip currents.
Waves will average five to nine feet and the NWS warns conditions could be dangerous to swimmers. A high-surf advisory is in effect until 9 p.m.
The heat wave began to make its way into the region on Monday, bringing a wave of extreme temperatures to all areas of San Diego County except the coast and upper mountains.