OAKLAND (CBS/AP) – As the weather heats up in the Bay Area, triple-digit temperatures are sweeping parts of the Southwest this weekend and leading some people in Arizona to fall ill from the sweltering heat.

The mercury quickly rose Sunday morning, with highs in the nineties forecast for the Bay Area. In Arizona, some areas of metropolitan Phoenix were expected to reach 110 before noon. Forecasters say the city could see a high of up to 120, approaching the record of 122.

Firefighters in north Phoenix rescued a 28-year-old woman who became unresponsive while mountain biking with friends in the morning. She was transported to a hospital, but later died.

A 25-year-old Phoenix man died Saturday of heat exposure while hiking.

People in Southern California were posting competing photos on Facebook and Instagram of their soaring thermometers.

Burbank and Glendale, just north of downtown Los Angeles, soared past 100 degrees by midday Sunday, with Burbank hitting a record 105.

The heat was no help to firefighters working to put out a brush fire in a LA neighborhood, where densely packed homes were briefly danger before it was knocked down.

Further northwest in the San Fernando Valley, some thermometers were reading close to 110 degrees, and Palm Springs in the inland desert hit 115.

The heat spurred state regulators to urge residents to voluntarily cut their consumption of electricity Monday.

KPIX 5 Weather Center: Current Forecast & Conditions

A strengthening ridge of high pressure lifting out of Mexico is on course to scorch portions of Arizona and southeast California on Sunday and Monday.

Inland temperatures for the Bay Area are forecast to reach into the nineties through Saturday.

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