Forecast for inland temperatures to stay in the triple-digits this week

America’s heat wave has caught up with California — at least the inland areas.

Sacramento has had six consecutive days above 100 degrees; an excessive heat warning is in effect from Merced to Bakersfield; and on Saturday Modesto tied its record for highest temperature for the date, at 105 degrees.

“In general, we’re about ten-to-fifteen degrees above normal for this time of year,” Holly Osborne, a meteorologist with the National Weather Service in Sacramento told me. “Today will be our sixth day of 100 or above in Sacramento, and we’re looking at temperatures being 100 or above for the rest of the week.” Osborne expects things to cool off, “moving into the weekend.”

The record number of consecutive days over 100 degrees in Sacramento is eleven, set in 2006. If the current heat wave holds up, it could tie for the second longest stretch, at nine. Temperatures like this may become more common in the future. In the California climate assessment released by the California Energy Commission last month, one projected outcome of climate change is an increase in the number of “extremely hot” days. In Sacramento, the number of days hotter than 105 degrees could inch up from four or five, to about 20 every summer, if global emissions of warming gases continue on their present course.

Osborne says overnight lows in the Sacramento Valley have been closer to normal, which is important, because cooler nighttime temperatures give people a chance to cool off. The southern San Joaquin Valley hasn’t seen much relief, though, according to Kevin Durfee, a meteorologist with National Weather Service in San Joaquin Valley.

[module align=”right” width=”half” type=”pull-quote”]”Overnight lows in Fresno and Bakersfield have been staying above 80 since the weekend.”[/module]

“Overnight lows in Fresno and Bakersfield have been staying above 80 since the weekend,” he said. “One reason why this weekend we had an excessive heat warning in effect for the San Joaquin Valley is, when nighttime lows do not get below 80 and daytime highs are well over 100, very close to records, that is pretty extreme.”

Cooling centers are open today in Kern County. They open when the temperature is predicted to be 105 degrees or higher. Different locations have different triggers for opening cooling centers. Sacramento County tracks nighttime lows, rather than daytime highs. If the temperature at night doesn’t dip below 75 degrees for three consecutive days, and if they’re hearing from area hospitals that people are coming in or calling in with heat-related issues, they’ll open cooling centers.

Chris Andis from the Sacramento County Office of Emergency Services says this week, they probably won’t (a local TV station points out that people tend to use shopping malls as informal cooling centers).

“We have hot weather. That’s what July and August are in Sacramento,” she said. But she also emphasized that it’s important in weather like this to keep an eye on others who may be feeling the heat. “Check on loved ones,” she said. “Especially people who are chronically ill, seniors and pets.”

And it’s not only living things that get hit by the heat. The California Independent System Operator, or Cal-ISO, which manages the state’s power grid, is asking customers to conserve electricity wherever possible until 6:00 p.m., and is issuing a Flex Alert for tomorrow.