OLYMPIA — Washington state’s death toll from last month’s record-breaking Pacific Northwest heat wave has risen to 78.

A majority of the deaths from the late June heat wave were in King and Pierce counties.

The state Department of Health said Thursday that a year earlier, Washington had just 7 heat-related deaths all summer. In the 5 years prior there were a total of just 39 deaths.

Acting State Health Officer Scott Lindquist says extreme heat waves are predicted to happen more often and last longer due to our changing climate.