Heat wave could cause blackouts

Utility Pacific Gas & Electric Co. is warning that extreme temperatures and overnight warmth may damage transformers, interrupting power.

Extreme heat expected locally for at least the next week.

Extreme temperatures expected this week will do more than shorten tempers and draw crowds to swimming holes.

Widespread and lingering heat across most of Northern California could disrupt electricity this week. PG&E is telling customers in Sonoma and nine other counties to prepare for possible shutoffs.

"Normally, at night when the temperatures go down, our equipment has a chance to cool down, but when we have this extreme heat, it's staying warm at night and our equipment never gets a break, so we can see heat-related damage to our equipment which can result in outages," said Megan McFarland, a PG&E spokesperson.

The outlook from the National Weather Service expects highs above 100 in many parts of the Bay Area.

"PG&E meteorologists are seeing a huge heatwave hitting most parts of our service area, and we're definitely getting prepared."

Overnight lows in the Sacramento Valley, also served by PG&E are forecast to barely fall below 80. That has the utility saying it's marshalling repair crews and equipment where problems are expected.

As to how long one can expect a blackout to last, there's no easy answer.

"Every outage is different, it really depends on what the outage is about, what kind of repairs are required, so many different factors we can't really give a ballpark like that," McFarland said.

There are a number of steps people can take right now that should help weather an interruption of electrical service.

"Charge up your cell phone, charge up your backup batteries, if you lose power during the heat wave you can always charge your cell phone in your car. Take a couple jugs of water, it it in your freezer, freeze it up and then if you do lose power move it to your refrigerator to prevent food from spoiling," McFarland said.

PG&E has the ability to request additional power from neighboring utilities should demand spike, but isn't expecting to have to.