MIAMI (Reuters)—The U.S. government climate agency cut its 2009 Atlantic hurricane season forecast Thursday, predicting there would be between seven and 11 tropical storms, with three to six becoming hurricanes.

The U.S. National Oceanic and Atmospheric Administration predicted one to two of those would be "major" hurricanes of Category 3 or higher, with sustained winds of more than 110 mph.

The agency had predicted in May that there would be nine to 14 tropical storms, with four to seven becoming hurricanes, and one to three strengthening into major hurricanes.

The change was based mainly on the arrival of El Niño, a periodic warming of sea waters in the eastern Pacific. El Niño can dampen Atlantic hurricane activity by increasing wind shear, a difference in wind speeds at different altitudes that can tear apart nascent cyclones.

In May, NOAA had calculated there was a 50% chance el Niño would develop.Now however, "El Niño is here," said Gerry Bell, the agency's lead seasonal hurricane forecaster.

The Atlantic-Caribbean hurricane season, which runs from June 1 to Nov. 30, has not generated any tropical storms so far. But the busiest part of the season is usually from late August to mid-October.

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