“Extreme heat is actually the deadliest type of weather event.”

BOSTON — More and more summer days in Massachusetts are reaching temperatures above 90 degrees, and climate resiliency planners say the trend is accelerating.

Sasha Shyduroff, clean energy and climate planner for the Metropolitan Area Planning Council, said historically, the Greater Boston area would see roughly 11 days over 90 degrees each summer, but by 2030, climate change is expected to push that to 40+ days per summer.

She pointed out extreme heat has many effects on communities, especially on people who use public transit or work outdoors, and even at schools that have limited air conditioning.

“Extreme heat is actually the deadliest type of weather event,” Shyduroff explained. “On average, it kills more people nationally than any other type of weather event. So, we should be thinking about extreme heat as similar to how we think about blizzards or hurricanes.”

She recommended drinking lots of water, avoiding strenuous daytime activity and finding an air-conditioned space, whether it’s at home, a friend’s house, a municipal cooling center or public library. She thinks cities should invest in renewable energy for cooling, to reduce emissions that, over time, exacerbate climate change.

Shyduroff added it’s important to check on neighbors, especially older people. She said while it’s hot for everyone, some groups are at greater risk for heat-related illnesses.

“Seniors, young children under five, pregnant people and nursing mothers, those with cardiovascular diseases, people who work outside, people experiencing homelessness,” Shyduroff outlined. “Those groups of people are all at increased risk.”

Shyduroff emphasized the Planning Council has worked with several communities on ways to increase utility-bill assistance and provide air conditioners, box fans or other personal cooling equipment. She said Metro Boston is underprepared for extreme heat, especially since the pandemic, when many people lost jobs or had their hours cut.

“We’ve heard from renters who are not allowed to install AC units, or have windows that don’t open or don’t have shades to cover their windows,” Shyduroff recounted. “And this has been especially worrisome for folks that live in public housing or affordable housing.”

She noted only 14% of homes in the region have central air conditioning, and she urged local, state and federal officials to advance policies that protect people most vulnerable to extreme heat.