An intense heat wave gripping the San Diego area in the waning days of winter is expected to linger for the rest of the work week and into the weekend, forecasters said Wednesday.
The unseasonable hot spell poses potential health hazards and has set a series of temperature records for March, according to the National Weather Service.
An NWS extreme-heat warning will remain in effect through 8 p.m. Saturday for local desert communities, with thermometer readings of 104 to 112 degrees likely — and possibly a couple degrees higher on Thursday and Friday, with nighttime only lows falling into the mid-70s.
Through Saturday, the first full day of spring, temperatures across the county will be 20 to 30 degrees above normal for this time of year, according to meteorologists.
A less severe heat advisory will be in effect through 8 p.m. Friday for the mountain areas, with highs in the 90s possible below 4,500 feet and into the 80s at higher elevations. A heat advisory will remain in effect until 8 p.m. Friday for coastal areas, where highs could reach the 90s, and the inland valleys, where temperatures in the triple digits are possible.
Dia Comeaux of La Mesa said she keeps cool by opening her windows at night and running her overhead fans in the house.
“And that cools everything down," she said. "(I) close the windows first thing in the morning and then it usually stays pretty cool till the afternoon.”
If it gets too hot, Comeaux said she will go to the movies or shop at grocery stores for the air conditioning.
A slight cooling should move in over the weekend into early next week, with higher coastal humidity spreading inland. Still, high temperatures for next Tuesday will range from around 5 to 10 degrees above average near the coast to 12 to 18 degrees above average for inland areas.
During prolonged heat waves, there's an increased chance of heat-related injuries, said Dr. Andrew Eads from Sharp Memorial Hospital.
“As these heat waves sort of drag on for several days, that a lot of people are sleeping in places that don't have air conditioning," He said. "They're never really getting kind of a true recovery in a cool place, and so that heat-related injury builds up over days.”
Eads said he typically sees complications three to four days into a heat wave. So far, that hasn't happened because nights have been cooler, allowing people to recover, he said.
Signs of heat distress include feeling light-headed, mental fogginess, dizziness and feeling incredibly fatigued and weak, Eads said. If that happens, he said people should find ways to cool down, including drinking cool water.
If symptoms don't improve, that's when people should go to the emergency room, he said.
On Tuesday, the summerlike weather set several local high-temperature records for Saint Patrick's Day — 96 degrees in Alpine, up from 92, set in 1978 (also a record for any maximum mercury reading in that rural town for the month of March); 93 in Chula Vista (86, 1978); 97 in El Cajon (91, 1978); 79 on Palomar Mountain (75, 1972); and 95 in Ramona (88, 2004).
Health officials advise the public to prevent heat-related ailments by drinking plenty of fluids, staying out of the sun, limiting strenuous activities to early morning or evening, taking refuge in air-conditioned spaces if possible and checking in on potentially at-risk friends, relatives and neighbors.
Children and pets should never be left in an unattended vehicle, even with the windows cracked, as vehicles can heat up to deadly levels in minutes when the mercury is this high.
Cal/OSHA, for its part, urged employers to take precautions to protect workers as temperatures rise.
"This is one of the first heat waves of the year, with temperatures rising above the seasonal average," officials with the state agency asserted in a prepared statement. "Employees may not yet be acclimatized to high heat and may need additional breaks and interventions when they adapt to the conditions. Cal/OSHA reminds employers to be vigilant, especially with newer employees, and ensure that employees have shade, water and rest breaks to prevent heat illness."
