LOS ANGELES The week-long heat wave in Southern California has claimed four lives and caused power outages to more than half a million customers, utility and local officials said on Tuesday.
Triple-digit temperatures lingered over some of Southern California for the seventh straight day on Tuesday, while most cities in the region saw temperatures in the mid-to-high 90s.
The heatwave is expected to break by Wednesday.
The Los Angeles County coroner's office said the deaths of four people appear to be linked to the heat, pending autopsies.
The bodies of a couple in their 80s were found in their Los Angeles home on Monday where inside temperatures were higher than 110 degrees Fahrenheit (43 Celsius).
The body of a 53-year-old woman living in her car was found on Sunday.
And just north of Los Angeles, the body of a woman in her 80s was found in an apartment in Pasadena. Inside, the temperature was 115 degrees F (46 C), according to authorities.
About 55,000 customers of Southern California's three biggest utilities were without power on Tuesday afternoon, down from 64,000 earlier Tuesday.
Each of the three utilities -- Southern California Edison, San Diego Gas and Electric and Los Angeles Department of Water and Power -- have either set or neared all-time record demand in the past few days.
The utility said its outages mid-afternoon Tuesday were down to 29,260 customers from 33,711 earlier Tuesday.
So Cal Ed, a subsidiary of Edison International, reported 29,260 customers without power on Tuesday afternoon, down from 33,711 earlier Tuesday, and said 538,053 of its 4.8 million customers had lost power since the heat wave began.
The LADWP had 26,000 of its 1.4 million customers without power on Tuesday and did not have a cumulative figure for outages since the heat wave began.
San Diego Gas and Electric, a subsidiary of Sempra Energy, reported only 204 of its 1.3 million customers had no power on Tuesday afternoon, down from 4,566 powerless on morning. About 85,000 have been without power since last week.
Northern California is not as affected and utilities there reported no heat-related outages.
The California Independent System Operator on Tuesday said demand statewide will drop to about 42,450 megawatts on Wednesday from 45,000 megawatts on Tuesday and from 48,600 megawatts last Friday.
No major grid problems were seen on Tuesday.
Normally, a megawatt can serve about 650 Southern California homes but that number drops during a heat wave.
So Cal Ed last Friday set a record for power demand at 23,303 megawatts and it also set a mark for Labor Day holiday demand at 22,100 megawatts.
The LADWP last Friday had the second highest demand in its history at 6,107 megawatts, second only to 6,165 megawatts set July 24, 2006.
SDG&E set a record demand on Monday despite it being a holiday and is expected to break that record on Tuesday, said spokesman Peter Hidalgo. Monday's peak demand was 4,636 megawatts, breaking last July's 4,502 megawatts.