NEW YORK California again urged customers to conserve power on Friday even though electricity demand for air conditioning should decline as temperatures along the coast continue to ease and many businesses shut early for the weekend.
Even though California has been baking for four days straight, its power companies have kept the lights on without any emergencies despite a plane crash that took down transmission lines near San Diego on Tuesday.
The state grid operator forecast demand for power Friday would reach about 44,000 megawatts, down from a forecast of about 45,000 MW on Thursday, before dropping to about 40,000 MW on Saturday.
That is still well below the state's all-time peak of over 50,200 MW set last July.
One MW powers about 700 homes in California.
Electricity traders noted that demand on Fridays is lower than other weekdays as businesses shut early for the weekend, reducing the usual late afternoon peak.
Meteorologists forecast temperatures in the major cities in California's Central Valley - Fresno and Sacramento - would still top 100 degrees Fahrenheit, down from over 110 F earlier in the week.
Along the coast, however, the mercury's highs would remain in the 70s and 80s in Los Angeles, San Diego, San Francisco and San Jose.
Elsewhere in the West, temperatures Friday will top 100 degrees in Las Vegas; Reno, Nevada; Tucson, Arizona; Billings, Montana; Boise, Idaho and as far north as Edmonton, Alberta.
The heat wave that blanked the West this week could spill east toward the Plains, Midwest and East Coast next week, some meteorologists warned.