Maryland really began to turn in the roaster Thursday, joining much of the rest of the country, now deep in the summer's worst heat wave.

The mercury reached 103 degrees in downtown Baltimore, with a heat index reading of 117 degrees. It was 100 at BWI-Marshall Airport, four degrees short of a record.

And there is little relief in sight. The region could see scattered thunderstorms Friday or Saturday afternoon, but forecasters don't expect a palpable break from the suffocating weather until a weak cold front arrives late Sunday.

The National Weather Service was forecasting a high of 104 degrees downtown Friday and 101 degrees Saturday. The airport could reach 102 degrees Friday before slipping to 99 Saturday.

As the region sweated, a small army of public health workers and volunteers mobilized in Baltimore to help the most vulnerable residents: seniors. The nations's public health officials recognize that high temperatures are the No. 1 weather-related killer and have been working to avert a mass tragedy like the deaths of 1,250 in 1980 from a heat wave and 700 deaths in Chicago alone in 1995.

Some city workers made phone calls Thursday to the city's oldest residents — including a 114-year-old man — to make sure they had air conditioning. Others stocked city and church cooling stations with water. The Fire Department added extra emergency medical services units. And Rosalie Pack started knocking on doors.

"We have to make sure they're OK because it's just so hot," said Pack. She's a volunteer member of the Community Emergency Response Team, a group of more than 300 volunteers recruited by the Mayor's Office of Emergency Management for a range of critical duties in their neighborhoods.

Pack, a senior herself at 68, was walking the streets of Brooklyn. She knows most of the older folks who remain in the enclave of Brooklyn Homes, including Betty Flint, who lives alone.

"Do you have water?" Pack asked Flint, who came to her townhouse door in shorts and a tank top. "Do you have air? Do you have food?"

Flint answered yes, though "air" was not an air conditioning unit, but a fan. Still, Flint was more concerned about some maintenance that was needed, and Pack said that she'd see what she could do — and that she'd likely check back soon.

Nationwide, the heat leads to hundreds of deaths among seniors each year, according to the U.S. Centers for Disease Control and Prevention, and the recent heat wave has claimed at least two dozen lives in Missouri, Arizona, Oklahoma andArkansas.

In Maryland, five of the six heat-related deaths this year have been those 65 or older, and last year almost half of the 32 who died were seniors, according to state data. Most in the state and nationally had an underlying health problem such asheart disease.

The Baltimore Health Department reported that 24 residents were admitted to city hospitals for heat-related illnesses between Monday and Wednesday. But that may not account for all illnesses.

"Many more [emergency department] admissions may be heat-related, but are not coded as such," said department spokesman Brian Schleter. And more may turn up as the heat wave drags on, and its effects accumulate.

The actions taken by the city, as well as the counties and state, are lessons learned from the deaths in Chicago and other areas, said Dr. Clifford Mitchell, assistant director for environmental health and food protection at the Maryland Department of Health and Mental Hygiene.

He said seniors, outdoor workers, children and those with underlying health conditions are primarily at risk, and officials need to be vigilant about communicating warning signs and getting people help.

"People are often unaware they are in trouble until it's too late, especially when people live alone," he said. "I fully anticipate seeing a significant number of excess deaths this year, even with all the attention being paid. It's a very difficult situation."

What makes the elderly so vulnerable is their inability to react quickly to extreme heat, said Dr. Alicia I. Arbaje, an assistant professor and associate director of transitional care research in the Division of Geriatric Medicine and Gerontology at Johns Hopkins Bayview.

Their blood vessels become stiffer and take longer to dilate, which delays blood to the skin and sweating to cool off. Many older adults also have decreased sensation, and their brains take longer to recognize they are thirsty.

In addition, many have diseases that further slow the body's ability to adapt to stress. Their medications only make matters worse. Diuretics, for example, lower blood pressure by expelling fluids, which dehydrates the body and becomes a threat in the heat. Over-the-counter allergy and sinus medications that many people take in the summer are also dehydrating, and depression and anxiety medications cause sedation and delays in sensing heat.

She recommends that seniors talk to their doctors about possibly lowering their medication in hot weather.

Arbaje said another problem with seniors is that they tend to have mobility issues, so they may get up for water and urinate less frequently.

But the most important thing for seniors may be ensuring they are cool.

"The No. 1 predictor of an adverse outcome is not having air conditioning," Arbaje said. "Studies show even temperatures in the 70s can be dangerous. It's a real problem for seniors who live alone. Someone needs to be with them or check on them and connect them to services if there is a problem."

That is why city officials are calling and visiting as many seniors as they can during the Code Red alert, which is in effect until Sunday, and urging others to check on their neighbors. There are 11 regular cooling stations open, plus a dozen additional ones. Residents can locate the nearest one by calling311 or going to http://www.baltimorehealth.org/coderedinfo.

Residents having a heat emergency should call 911, officials said.

The excessive heat warnings for all of Maryland east of the Alleghenies were extended through Saturday evening. Baltimore's Code Red Heat Alert was extended through Friday.

Friday's air quality forecast from the Maryland Department of the Environment was for Code Red conditions, with ground-level ozone levels rated unhealthy. Sensitive groups are urged to avoid prolonged exertion, and everyone is advised to limit outdoor exercise.

The cold front on Sunday should drop the daytime highs to the lower 90s, but temperatures will stay in the 90s at least through next Thursday, forecasters said. That would make it 12 days in a row with highs of 90 or higher. The record for Baltimore is 25 days, set from July 12 through Aug. 5, 1995.

As tropical as it was, the weather led organizers to put off Thursday night's planned Afro-Caribbean "Dancing in the Plaza" event at Baltimore's Hopkins Plaza. They hoped to reschedule for a (cooler) date in September.

BGE officials said the region's generators and transmission lines were keeping up with the demand for electricity for fans and air conditioners.

"The system continues to hold up well," said BGE spokeswoman Linda Foy. "At this point it does not appear that we will set a new peak usage record, although we could get close by [Friday]."

On Thursday, Olivia Farrow, a deputy city health commissioner who is in charge of coordinating Code Red days, made about 20 of the 1,065 calls to seniors herself.

"Everyone I called had air conditioning, but they seemed appreciative someone checked," she said.

Meanwhile, in Brooklyn, Pack was still trolling the neighborhood. Outside the community center where she works, she ran into Francis Toporzyski, a 63-year-old who uses a scooter to get around. She gave him some information about handling emergencies and made sure he knew how to call for help.

He said he had air conditioning at home but wanted to get out of the house.

He nodded at Pack, wiped his brow and said, "She's always checking on me."

meredith.cohn@baltsun.com

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