MIAMI - Tropical Storm Chantal formed Tuesday morning in the Atlantic Ocean between Bermuda and Massachusetts, but it was not expected to threaten the United States, forecasters said.

The storm had maximum sustained winds of 40 mph and was centered about 330 miles south of Halifax, Nova Scotia, according to the National Hurricane Center. It is moving northeast at about 23 mph.

The threshold for a tropical storm is sustained winds of 39 mph. When those winds reach 74 mph, it becomes a hurricane.

THIS IS A BREAKING NEWS UPDATE. AP's earlier story is below.

MIAMI (AP) - A tropical depression gained speed early Tuesday off the East Coast between Bermuda and Massachusetts and was expected to briefly become a tropical storm.

The depression was centered about 380 miles north of Bermuda and 380 miles southeast of Chatham, Mass., on Cape Cod, according to the National Hurricane Center.

The system could affect Newfoundland late Wednesday or early Thursday, but it will not be too strong, hurricane specialist Eric Blake said.

At 5 a.m. EDT, it had top sustained winds near 35 mph and was moving toward north-northeast at 21 mph, forecasters said. That's an increase in speed since a 16 mph reading six hours earlier.

The third depression of the season was expected to grow stronger but ''as a tropical system it has a very short life ahead of it,'' said James Franklin, a senior hurricane specialist.

The depression would be named Chantal if it reaches tropical storm strength, with winds of at least 39 mph.

There have been two named storms in 2007: Subtropical Storm Andrea, which formed in May, and Tropical Storm Barry, which formed June 1, the first day of hurricane season.


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