Hurricane Bertha weakened back into a less-menacing tropical storm on Sunday after stalling for a day near the British colony of Bermuda, the US National Hurricane Center said.
The top sustained winds of what had been the first hurricane of the 2008 Atlantic storm season slipped to 70 miles per hour (115 km per hour), below the 74 mph (119 kph) threshold at which tropical storms are classified as hurricanes, the Miami-based hurricane center said. Bertha was expected to weaken a little more and then pass slowly "not far to the south-east and east" of Bermuda, a wealthy mid-Atlantic offshore finance center, when it finally began moving again, the hurricane center added.
At one point a "major" Category 3 hurricane on the five-step Saffir-Simpson scale of storm intensity, as Hurricane Katrina had been when it came ashore near New Orleans in 2005, Bertha weakened because of its lack of movement. Its energy had churned up colder waters from beneath the sea surface, depriving it of the warm water that fuels tropical storms.
Bermuda, which is also a major tourist resort, has strict building codes and a tropical storm is unlikely to pose any significant threat to its 66,000 people. Oil markets had kept a wary eye on Bertha after it formed because of the potential of hurricanes to cause havoc among the oil rigs of the Gulf of Mexico.
But the Gulf has not been in Bertha's track for many days. By 8 am EDT (1200 GMT), Bertha was around 220 miles (355 km) south-east of Bermuda, and had not moved for a day. "A drift toward the north-west is expected to begin later today and continue into Monday," the hurricane center said. Hurricane experts have forecast that the 2008 Atlantic storm season will be average or above average.
The long-term average is for 10 tropical storms to form between June 1 and the end of November, of which six become hurricanes. Bertha formed near the Cape Verde Islands off Africa and its development so far east so early in the season is viewed by some hurricane experts as ominous. Storm activity does not usually get into high gear in the Atlantic until August.