Ana Becomes First Named Storm of Atlantic Hurricane Season

The Atlantic Ocean recorded its first named storm of hurricane season on Saturday after a subtropical storm developed northeast of Bermuda, the National Hurricane Center said.

The storm, Ana, developed well before June 1, when hurricane season begins. It was the seventh year in a row that a named storm developed in the Atlantic before the official start of the season.

After developing as a subtropical storm on Saturday, Ana transitioned into a tropical storm on Sunday morning, thanks to a change in its wind flow.

Early on Sunday, the storm had winds of up to 40 miles per hour and was moving northeast at 14 m.p.h. For Tropical Storm Ana to become a hurricane, it would need to reach wind speeds of up to 74 m.p.h., which is not expected to happen, the Hurricane Center said.

Andrew Latto, a hurricane specialist with the center, said in a forecast update that Tropical Storm Ana was expected to dissipate on Sunday.

“Ana is barely holding on,” Mr. Latto said.

Before Ana transitioned into a tropical storm on Sunday, Dennis Feltgen, a spokesman and meteorologist at the Hurricane Center in Miami, said that subtropical storms can still have significant effects.

“They can do just as much damage and have just as much of an impact,” he said. “That’s probably not going to happen with this one.”

The storm was expected to drift farther northeast into the Atlantic Ocean before dissipating. It is not expected to reach land, the Hurricane Center said.

A storm is named only after it reaches wind speeds of at least 39 m.p.h. Although the storm that formed on Saturday had wind speeds similar to those of a tropical storm, it was considered subtropical because of its position and wind flow, Jack Beven, a senior hurricane specialist with the center, said in an update on Saturday.

Tropical Storm Ana, however, was the first in what is expected to be a busy hurricane season.

The Climate Prediction Center said that the Atlantic could have 13 to 20 named storms this year, of which six to 10 could become hurricanes. Three to five could become major hurricanes, with winds greater than 111 m.p.h. — enough to damage well-built homes, uproot trees and make electricity and water unavailable for days to weeks.

“Although NOAA scientists don’t expect this season to be as busy as last year, it only takes one storm to devastate a community,” Ben Friedman, the acting administrator of NOAA, the nation’s climate science agency, said this week.

Last year, a record-breaking 30 storms developed in the Atlantic, 13 of which became hurricanes, including six that strengthened into major hurricanes, according to NOAA.

It was the highest number of storms on record, surpassing the 28 from 2005, and became the second-highest number of hurricanes on record, the agency said. Last September, there were five active storm systems simultaneously moving through the Atlantic.

There were so many storms in the Atlantic last year that NOAA depleted a 21-name list of storms for the season and had to resort to naming storms after Greek alphabet letters for the second time in the agency’s history.

The next named storm that develops in the Atlantic this year will be Bill, followed by Claudette.