After three hours riding in the sludge, Ken Moody was giving up on his bicycle for the day.

“This is too much,” he said yesterday. “I’m going to get hurt.”

As a bike messenger, Mr. Moody, a well-insulated 55-year-old with silver whiskers in his beard, had spent the day dealing with what most New Yorkers faced only on the way to and from work: the aftermath of the city’s greatest snowfall since it began measuring such things.

By midday, when Mr. Moody decided to hang up his bike at the offices of Breakaway Courier Services, one of Manhattan’s largest courier companies, the sun had melted large quantities of snow, leaving behind pond-like puddles of sludge on main thoroughfares. Shaded side streets were still covered with ice and packed snow. Mounds of snow created by the plows pushed cars and bicyclists onto narrower paths in the centers of streets.

“There is no shoulder, so you have to ride with the traffic,” a bike messenger with Mothers Messengers, Adam Stout, 25, said. “It’s a mess out there.”

Only 50 of the 80 couriers who usually work at Breakaway called in for duty yesterday. Of those, half opted to use mass transit for the day, the general manager, Andrew Young, said. Many clients were having difficulty making it to work as well, he said. The service was a third less busy than on an ordinary day. (On a typical Monday, Breakaway’s couriers – on foot, in trucks, and on bikes – deliver between 1,500 and 1,700 packages.)

Other courier services said they were similarly swamped because many messengers didn’t call in for work.

On the day before Valentine’s Day, an important day for delivery services, the situation could have been much worse, Mr. Young said. The worst condition, cringed at by messengers worldwide, is a day with temperatures just above freezing and pouring rain.

“The slush isn’t the most dangerous thing for a messenger,” Mr. Young, who was a bicycle messenger for eight years, said. The real pitfalls are crowded streets, slippery metal, and obstacles hidden by water, he said.

One of the most notorious traps for rookie messengers is a deep pothole or sewer grate filled with water to the point that it looks like a small puddle – a kind of mirage. Cyclists hit them at speed and go flying into the street. It doesn’t help that wet brakes don’t stop bikes as quickly as dry ones, according to a pamphlet given to new messengers.

Mr. Moody said he gave up after venturing to the far East and West sides of Midtown, where many streets weren’t yet plowed. On his bike, he was on the way to making half as much money as usual and so wasn’t upset to be switching to the subway, he said.

A sprier veteran, Hilario Flores, 31, was faring considerably better, despite having to ride through an unplowed bicycle lane on the Manhattan Bridge from his home in Brooklyn. By 1:30 p.m. he had made 22 deliveries and was well on his way to make a lot more, he said. A good day usually yields 25-35 deliveries; more than 40 is called “legendary.” At 20 deliveries a day, a messenger’s weekly salary comes out to about $400 before taxes.

“It’s very tough today. Not too many people showed up” for work, Mr. Flores said. “So, there’s a lot more work for me.”

Mr. Flores, who hails from Mexico City, said he has been delivering packages almost seven days a week for 10 years.

By evening, the New York Bicycle Messenger Association said it had heard no reports of bicycle messenger accidents, which is consistent with trade wisdom: The bad accidents, and sometimes deaths, happen when the weather is warm and cyclists get too comfortable and go too fast. The worst complaint yesterday, it seemed, was exceeding discomfort.