Tri-Cities heat wave! How hot will it get, how long will it last?

The temperature could reach a blistering 110 degrees in the coming week as the Tri-Cities, Wash., swelters under a heat wave that may linger for up to 10 days.

The hottest day is expected to be Tuesday, July 9, with 110 degrees forecast, followed by Wednesday at 109, according to the National Weather Service.

Both could set new daily temperature records, including breaking one record that has stood for more than a century.

The hottest temperature on record for July 9 is 106 degrees in 1905 and for July 10 it is also 106 set in 1975, according to the weather service.

The Weather Channel forecasts even hotter weather , with a high of 111 predicted for Wednesday and 10 straight days of 100-plus temperatures.

The National Weather Service has issued an excessive heat warning from July 5 through at least Thursday, July 11, which is as far out as it forecasts.

Cooling centers

The Benton Franklin Health District is promoting temporary cooling centers for people who need relief from the heat.

They include public libraries in Benton and Franklin counties, the First Avenue Center at 505 First Ave. in Pasco, the Columbia Center mall in Kennewick, the Richland Community Center at 500 Amon Park Drive, Becky’s Coffee Corner at 1120 Meade Ave. in Prosser and Renz Farmers Insurance Agency at 1108 Meade Ave. in Prosser.

You also can call 211 at any time to find the nearest cooling center and other resources.

Adding to the danger from the heat wave are the warm overnight temperatures that will give limited relief to people whose bodies have been too hot during the day.

Lows in the Tri-Cities are forecast to be in the 70s from Monday night through at least Wednesday night, according to the weather service.

For the first half of July in the Tri-Cities normal highs are in the low 90s and normal lows are in the 50s.

Hot weather rules for WA workers

The weather service recommends staying in air-conditioned buildings and checking on elderly neighbors and relatives and those who may not have air-conditioning.

It warns that temperatures in unattended cars could be deadly within minutes to pets or children.

If you plan to be outside, try to limit strenuous activities to early morning or evening, it said.

The Washington state Department of Labor & Industries requires employers give workers in 90-degree heat a 10-minute paid cool down rest period every two hours. At 100 degrees or higher, the requirement for breaks becomes 15 minutes of paid cool down rest every hour.

People outdoors in the heat should move to the shade and drink water if they have symptoms of heat exhaustion , such as weakness or cramps; headaches, dizziness, nausea or vomiting; cold, pale and clammy skin; and a fast, weak pulse.

Emergency medical care is needed if skin is hot, red and dry with no sweat and there is a fast, strong pulse.

Heat wave power concerns

With air conditioners expected to be on full blast across the state, he Bonneville Power Administration made a “no touch” request to Energy Northwest for the Northwest’s only commercial nuclear power reactor, the Columbia Generating Station by Richland .

It has asked Energy Northwest to limit nonessential maintenance that could either require a reduction in power or pose a risk to sustaining 100% generation at the nuclear plant from July 5-11 as the heat wave increases demand for power.

The nuclear reactor is the third largest electricity generator in Washington state, behind the Grand Coulee and Chief Joseph dams.

In the historic heatwave of late June and early July 2021, Tri-Cities area utilities warned their customers that rolling blackouts were possible as extreme heat puts stress on its transmission system.

Thousands of Spokane-area customers of Avista utilities lost power periodically on two days as the utility was required to reduce electric load on its distribution system and turn off power temporarily.