July 6 (Reuters) - Forecasters at Colorado State University for a second time raised their estimate for tropical storms during this year's Atlantic hurricane season, citing record warm sea surface temperatures. The group had last month raised its outlook to a near-normal season and number of storms. "Most of the tropical and subtropical Atlantic now has record warm sea surface temperatures," Colorado State's Tropical Meteorology and Climate Research group said in its latest update. The effect of El Nino, a weather phenomenon that suppresses Atlantic hurricane activity, this year has been offset by very hot ocean waters. "The high chance of a robust El Nino is why CSU's hurricane forecast is not for every more activity," wrote CSU researcher Phil Klotzbach.

---

Persons: El, Phil Klotzbach, CSU's, Gary McWilliams, Marguerita Choy, David Holmes, Conor Humphries Organizations: Colorado State University, Climate Research, CSU, El Nino, U.S . National Oceanic, Atmospheric Administration, Thomson Locations: Colorado