An El Nino may be about to form in the equatorial Pacific Ocean during the second half of 2012, the U.S. National Weather Service announced Thursday.
"Overall, the forecaster consensus reflects increased chances for El Nino beginning in July-September 2012," the agency said in a monthly update.
Based on the prediction, the northern United States could be in for a warmer and drier winter than average, while the Southwest and Southeast could find itself with more rain than usual.
El Nino conditions are characterized by unusually warm ocean temperatures in the Equatorial Pacific that normally peak during the Northern Hemisphere "cool season."
They occur every three to five years with stronger events generally occurring every 10-15 years. El Nino conditions have important consequences for global weather patterns.
The phenomenon increases Atlantic wind shear that can keep tropical systems from forming, decreasing the total number of storms during the June 1 to Nov. 30 season.
