Maryland's deadliest summer on record claimed at least 59 lives, and 37 of the dead were 65 or older, a group that makes up nearly one in four Potomac residents.

The Maryland Department of Health reported 59 heat-related deaths since May, The Baltimore Banner reported Thursday, Sept. 3. That shattered the previous state record of 46, set in 2012 when a derecho knocked out power for nearly 2 million Marylanders. Last year's total of 36 had already been the state's worst in over a decade.

Of the 59 who died, 28 died indoors.

According to 2019–2023 American Community Survey estimates, about 11,088 Potomac residents are 65 or older, roughly 24% of the community's 45,902 population. About 10% of all Potomac households consist of someone 65 or older living alone, according to 2020 census data.

Summer heat broke records

State climatologist Alfredo Ruiz-Barradas found Maryland experienced six more days than normal above 86 degrees through July, along with two extra heat waves. During a heat wave over the July 4 weekend, overnight temperatures stayed above 68 degrees for more than a week.

"Even if a day in the high 80s doesn't sound extreme, hot afternoons followed by warm nights are a dangerous combination for people who work outdoors or lack access to reliable air conditioning," Ruiz-Barradas said.

By the end of July, 48 people had already died. As of an Aug. 6 update to the state's dashboard, the count stood at 50, with roughly 1,300 emergency room visits and 1,260 EMS calls for heat illness statewide. Heat deaths in Maryland have climbed sharply since 2022, when five were reported for the entire summer.

New AC law took effect June 1

A new state law, Senate Bill 12, took effect June 1. It requires air conditioning in all new buildings with 10 or more units. Existing buildings must add AC the next time they undergo significant maintenance to their electrical or heating systems.

Del. Mary Lehman, who represents District 21 in Prince George's County, sponsored the legislation and modeled it on ordinances already in place in Prince George's and Montgomery counties. Montgomery County had already mandated air conditioning in rental buildings before the state law took effect, according to The Banner. Lehman was stunned by this summer's death toll and has expressed concern about how long it could take to bring older buildings into compliance, The Banner reported.

What Potomac residents can do

Clifford Mitchell, director of the Maryland Department of Health's Environmental Health Bureau, said every heat death is preventable. Johns Hopkins University professor Ben Zaitchik, who researches climate change impacts on urban neighborhoods, called the spike surprising but said heat deaths can be stopped by getting people into air conditioning and providing water.

"We know what to do to prevent every single one of these deaths," Mitchell said.

The health department urges residents to check on older neighbors and relatives, especially those living alone. Residents who need a cool location can call 211 to find the nearest cooling center. The heat index in the Baltimore and Washington areas reached 100 degrees on Thursday, Sept. 3, and the death toll could still rise.