San Diego County logged 378 heat-related 911 calls through mid-September, surpassing the full-year 2025 total by 131. KPBS first reported the county data Tuesday, Oct. 6.

The record comes as an extreme heat warning from the National Weather Service (NWS) remains in effect for San Diego County coastal areas, including Encinitas, until 8 p.m. Thursday, Oct. 8. The NWS expects highs in the mid-80s to lower 90s at the beaches, upper 90s on the mesas and overnight lows in the low 70s.

Two heat waves drove the spike. County data show 35 calls between March 13 and March 21 and 62 calls between Sept. 7 and Sept. 11. Sept. 8 set the single-day record with 23 calls.

Those numbers may be undercounts, according to Deputy Fire Chief Willy Melendez of the San Diego Fire-Rescue Department. Melendez told KPBS that callers often report symptoms like headache, nausea or dizziness without mentioning heat.

"When calls come in, we don't necessarily (know) unless they're very specific on the 911 call that they're heat-related," Melendez said.

Call volume surged Saturday, Oct. 3. Melendez said the city of San Diego's metro dispatch center fielded 925 calls in a 24-hour period, a 42% increase. The city recorded 729 incidents that day, up 41% compared to the average over the past three years.

More than 400 people were transported by ambulance to hospitals Saturday, a 30% jump from the same day in 2025, according to the city of San Diego. The city has added ambulances and extended cooling center hours in response, Melendez said.

No Encinitas-specific call data were included in the county figures. Most calls came from neighborhoods in the city of San Diego. Men accounted for 231 of the 378 calls, and a majority of callers were between 15 and 44 years old.

San Diego County Public Health Officer Dr. Sayone Thihalolipavan attributed the higher rate among men to the number of people working or playing sports outdoors.

Residents looking for relief can visit a county Cool Zone, a free air-conditioned public space. San Diego Public Library branches in the city of San Diego have extended hours until 8 p.m. Wednesday, Oct. 7, and Thursday, Oct. 8. Encinitas-area residents can find nearby locations or arrange transportation by calling 211.