TOKYO, May 13 (Reuters) - Japan's weather bureau said on Friday that conditions were nearing for the El Nino phenomenon to form in the equatorial region of the Pacific, and that there was an 80 percent chance that it would be seen by the northern hemisphere summer.
El Nino is accompanied by high air pressure in the western Pacific and low air pressure in the eastern Pacific. El Nino phases are known to last close to four years; however, records demonstrate that the cycles have lasted between two and seven years... Wikipedia
Source: ANNnewsCH