SAN DIEGO -- A powerful storm cell dumped rain on parts of East County Tuesday afternoon, unleashing winds that blew trees down causing traffic backups.
The localized thunderstorm hit Rancho San Diego and Spring Valley at about 1:30 p.m. and moved toward the coast, according to Fox 5 viewers who posted a dozens of photos of the aftermath to the station Facebook page.
Cal Fire crews were assessing the damage at a shopping center at Avocado Boulevard and Calle Verde near Highway 94, agency spokesman Kendal Bortisser said. A Fox 5 photographer sent to the scene said it looked like a hurricane had blown through the area.
The stubborn monsoonal heat wave kept the San Diego area roasting again Tuesday and added to the misery by generating East County lightning, heavy rain, hail and stiff winds that sent trees and power lines crashing down onto roads and buildings.
The late-summer onslaught of oppressively sultry conditions once more hiked temperatures up into the triple digits inland and spread wilting humidity throughout the county.
In the early afternoon, thunderheads created by the sticky swelter erupted in a storm that sent down heavy precipitation -- some of it in the form of frozen pellets -- and kicked up powerful winds in Spring Valley, Rancho San Diego and Casa de Oro, authorities said.
The squalls continued, off and on, into the evening. About 6 p.m., gusts tore a hangar off its moorings at Montgomery Field airport in Serra Mesa, according to the San Diego Fire-Rescue Department. The structure blew into several airplanes, knocking two of them over and causing a roughly 30-gallon fuel spill, SDFRD spokesman Joe Amador said.
The winds also damaged electrical-transmission equipment, leaving about 18,000 homes and businesses from El Cajon to La Jolla without power, according to San Diego Gas & Electric as of early evening. The blackouts were expected to variously last into the night and early Wednesday morning, the utility reported.
In the East County, the storm knocked over dozens of trees along with power poles, damaging homes, vehicles and commercial structures and blocking roads, Cal Fire Capt. Kendal Bortisser said.
The extent of the damage was not immediately clear. No injuries were reported, Bortisser said.
Meanwhile, students at schools without air conditioning in San Diego, Chula Vista, Coronado and National City were sent home early for the second consecutive day.
While the Coronado, National and Sweetwater districts planned to maintain a minimum-day schedule again Wednesday, the San Diego Unified School District has opted to return to a normal schedule for all schools, whether or not they have air conditioning.
“Our criteria for determining the move to minimum day was based on a combination of forecast temperatures of 95 or higher and a heat index of 103 or higher for those schools in the district which did not have 100 percent air conditioned classrooms,'' according to a district statement. “None of our schools are forecast to have the combination of 95+ temps/103+ heat index on Wednesday.''
About two-thirds of SDUSD schools were put on minimum-day schedules. They included Clairemont, Crawford, Garfield, La Jolla, Madison, Mira Mesa, Mission Bay, Morse and University City high schools.
Repairs were underway on air conditioning systems, and portable cooling units were installed in some bungalows, according to the district.
The affected Sweetwater Union High School District include Mar Vista Academy, Castle Park and Hilltop middle schools, and Chula Vista, Mar Vista and Sweetwater high schools.
Those trying to beat the heat can head to more than 100 air-conditioned buildings, such as libraries and recreation centers -- dubbed “Cool Zones.'' A list of county Cool Zones is available at CoolZones.org. or by calling 211.
Forecasters urged people to schedule outdoor activities for the cool of the morning or in evening, to take frequent breaks in shady or air-conditioned areas and to know the signs of heat exhaustion and heat stroke. Those planning to be outside were advised to wear light, loose clothing and to drink plenty of water.
San Diego Gas & Electric said it would implement its “Reduce Your Use'' rewards program again Wednesday. Under the program, customers can receive a bill credit for not using as much electricity from 11 a.m. to 6 p.m. Information on how to sign up can be obtained online.
The utility encourages San Diegans to close blinds and curtains during the warmest hours of the day, raise the central air conditioning system's thermostat setting four to six degrees, health permitting, run major appliances and pool pumps before 11 a.m. or after 6 p.m., and unplug chargers and power strips.
The heat and mugginess were expected to continue Wednesday as remnants of Hurricane Odile keep swamping the region, according to the National Weather Service. A cooling trend should begin Thursday and bring temperatures back down to near-normal readings by the weekend, the NWS advised.
State Route 163 was closed around 6 p.m. for crews to clean up downed trees. Mission Center Road at Hazard Center had backed up traffic due to fallen trees.