Poway urged residents to use two free Cool Zones as a National Weather Service Extreme Heat Watch took effect Friday, Oct. 2, across San Diego County.

The watch runs from 10 a.m. Friday through 9 p.m. Wednesday, Oct. 7. The NWS forecasts temperatures in the upper 90s to low 100s for inland valleys, with Santa Ana wind gusts of 25 to 45 mph and up to 60 mph at the windiest spots through Monday, Oct. 5, ABC 10News reported.

Saturday, Oct. 3, is projected to be the peak. Nearby inland cities could hit 102 in Escondido and 97 in Mira Mesa, the San Diego Union-Tribune reported. No specific Poway forecast was available.

Where to cool off

The city's two designated Cool Zones are free and open to anyone, according to the city's advisory. The program is managed by San Diego County Aging & Independence Services and San Diego Gas & Electric.

Mickey Cafagna Community Center (Community Park lounge), 13094 Civic Center Drive. Open 8 a.m. to 5 p.m. Monday through Friday. Closed weekends. Phone: (858) 668-4671.

Poway Branch Library, 13137 Poway Road. Open seven days a week with varying hours. Monday and Thursday: 10 a.m. to 6 p.m. Tuesday and Wednesday: noon to 7 p.m. Friday through Sunday: 10 a.m. to 5 p.m. Phone: (858) 513-2900. The city advises residents to check the library's website for any schedule changes.

Trail warnings

The city designated conditions at Lake Poway and Blue Sky Ecological Reserve as dangerous for hiking, especially with pets. Heat-related incidents rise with the temperature across Poway's 78 miles of trails, the advisory stated.

The NWS advised residents to drink plenty of fluids, stay in air-conditioned spaces, avoid direct sun and check on relatives and neighbors. The agency also warned against leaving children or pets in unattended vehicles, where interiors can reach lethal temperatures within minutes.

Power shutoff risk

SDG&E notified customers of possible public safety power shutoffs (PSPS) from 5 a.m. Friday through 6 p.m. Monday, Oct. 5, potentially affecting about 35,000 customers across inland communities. Poway is among the areas that could lose power, NBC 7 San Diego reported. SDG&E also advised setting thermostats to 78 degrees or higher between 4 and 9 p.m. to reduce strain on the grid.

NWS forecaster Kyle Wheeler told the Union-Tribune the warm weather would persist "late into next week." The Climate Prediction Center forecasts an 80 to 90 percent chance of above-normal temperatures through mid-October, according to ABC 10News.

The Extreme Heat Watch expires at 9 p.m. Wednesday, Oct. 7, but the NWS may upgrade it to a warning or extend it.