It's over a hundred degrees at sunset in Locust Point, but still there are groups of people — old, young, middle-aged — gathered on corners and standing out on their front steps, from Decatur Street to Reynolds Street. They look sweaty and tired, but their faces light up when they hear a familiar jingle and see a bright aqua-blue-and-white truck turn the corner.

It's the ice cream truck, Tammy Radtke at the wheel.

"How you's doing?" comes the familiar voice from within the rolling summer concession. "How's your wife? How's your daughter? The usual tonight? You're not sitting out in this heat are you?"

Radtke is better known to neighborhood residents by her business name, Miss Twist. She's the ebullient blonde who drives the Miss Twist ice cream truck every Monday, Wednesday, Friday and Saturday, from 6:30 p.m. to 11 p.m., Decatur Street to Riverside Park.

She plies the narrow streets of South Baltimore selling ice cream — $1.25 for a cone, $3.50 for a sundae or shake, $5.00 for a banana boat — making a point to always stop at the same place on each street.

Just a few minutes into her route makes clear that Radtke is more than just the ice cream truck driver in Locust Point. After 15 years in business, she's a neighborhood friend.

She knows just about everyone's orders, and when a line forms she makes sure to ask each person how they're doing, how their vacation has been, how their family is, catching up as she pours toppings on their sundaes and mixes their milkshakes. Then she leans through her window to carefully hand it over and give a wave.

"I love them. When I'm not at work I think about my customers a lot, I really do," said Radtke, 44, as she steered her truck past rowhouses of brick and formstone, the speakers playing B.J Thomas' "Raindrops Keep Falling On My Head."

"The people," she said. "The people's the best part."

Radtke first got started in the business through her husband, Don, who is a generator technician. He was working on a customer's generator when the man told him, "You work too hard, you should go into the ice cream business," she recalls.

"My husband came home laughing, and I said, 'That sounds like a really good idea!' "

Though it took a while to get started — Radtke's husband bought an empty truck shell and fitted out their Miss Twist truck on his own, adding a generator, sinks, and condiment boxes — they were in business by October of 1995, and have been ever since. Radtke sells soft-serve ice cream; the machine is powered by the generator her husband built.

"I never thought of it as short-term, long-term," she said. "I just wanted to do it, and here I am fifteen years later!"

Though all types of people wait for her to come around in the evening, Radtke is quick to point out that unlike what one might expect, most of her faithful customers are adults.

"You ever see a child jumping up and down when they're coming to get ice cream? You see adults do that too and it really makes you laugh," she said.

Helen Kazmarek, 81, is inside her living room when Radtke arrives, but she sees the truck and comes running. According to Radtke, Kazmarek, who is one of her longest-standing customers, would always get a vanilla sundae with walnuts until recently, when she realized she was allergic to the walnuts. Now, she only gets a small cup of vanilla ice cream, but her enthusiasm for Radtke has not flagged.

Kazmarek says she'll even interrupt phone calls to greet Radtke when she comes around. She has lived in Locust Point nearly all her life, and remembers other ice cream trucks in town, but considers Miss Twist the best.

"Nobody can beat Tammy, nobody. She's the greatest. Every time I hear her music I come out," she said. She beams up at Radtke, who already has her vanilla cup ready, then touches her hand. "God bless, Tammy."

One year Radtke missed a season due to illness, and residents, worried that she might have moved or died, put an ad in the newspaper, asking "Where Is Miss Twist?"

"I told my husband, 'You better get that truck ready now!' " Radtke said. "They put in another article afterwards that said, 'Miss Twist has been found.' "

At around 9 p.m., before heading to Riverside Park, Radtke pays a visit to one of her favorite customers, an elderly man who lives on Reynolds Street. He recently had to cut back on his ice cream because of his health, but still she stops her truck to chat and visit if he's out.

"Don't get up," Radtke calls out her window. "I'll come over to you!"

She turns off her engine, and climbs out of her truck to greet him. She won't be selling ice cream to him today, but no matter.

"How was your doctor's appointment? What did the doctor say? No, I understand. … Your health comes first," she says, patting him on the shoulder.

As of early May, Radtke had set up a Facebook page to alert her customers when she'll be around, and when she won't. Some customers get irritable if they don't know when she won't be coming, Radtke says, so when she's on the route she tries to let everyone know. She plays her music in between stops, then turns it off when she's stopped to let people know she's waiting.

"I'll wait for a couple minutes, and then roll right along," she says, taking one last look around.

Unless of course, she sees someone running.

"Always, always stop for the customer. We do have people running after us," she says with a smile as she flicks on her music again and moves on to another street.

sarah.tan@baltsun.com