An unusually strong high-pressure system continued driving up temperatures across the region today, beginning what is expected to be a week of "dangerously" hot conditions that could set daily or monthly records for March heat.
The National Weather Service issued an extreme heat warning that will be in effect from 10 a.m. Wednesday through 8 p.m. Saturday for the San Diego County deserts, with temperatures of 104 to 112 degrees expected — possibly reaching a couple degrees higher on Thursday and Friday, with lows falling only into the mid-70s.
"High temperatures this week will be 20 to 30 degrees above normal for this time of year," according to the NWS. "Record breaking heat is likely."
A less severe heat advisory will be in effect from 10 a.m. Wednesday through 8 p.m. Friday for San Diego County mountains, with highs in the 90s possible below 4,500 feet and into the 80s at higher elevations. A heat advisory is already in place and will remain in effect until 8 p.m. Friday for coastal areas, where highs could reach into the 90s, and San Diego County valleys, where temperatures in the triple digits are possible.
"Most days this week have the potential for daily temperature records to be broken or tied, with the potential for monthly temperature records to be broken or tied Wednesday through Friday," forecasters said.
A weak offshore flow will bring wind gusts of 25 to 40 mph through Tuesday in coastal mountain foothills and below passes.
Temperatures are expected to peak in coastal areas and the western valleys on Tuesday, with other inland areas topping out later in the week.
"Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors," forecasters advised. "Do not leave young children and pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke."
Cal/OSHA urged employers to take precautions to protect workers as temperatures rise across the state.
"This is one of the first heat waves of the year, with temperatures rising above the seasonal average," the agency said in a 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."
