Taffy wrote:I have been reading the posts about the results of an El Nino. I have become confused on the results stemming from a weak El Nino and a Moderate/Strong El Nino. I seemed to come away with the impression that a weak El Nino meant a much more severe and wet winter than a moderate or severe El Nino. I can't understand how that could be and I would love the results explained for each strength of an El Nino.
Thanks.
El Nino has far ranging effects from tropical cyclone activity in the Atlantic and Pacific to droughts in Australia to floods in the southern CONUS. Without going into too much detail, El Nino winters can be severe in the northeast, only that in a strong Nino, the pattern would be progressive enough so that any snowstorm in the northeast wouldn't be blocked. Same cannot be said for a weaker Nino when the strong subtropical jet associated with all Ninos can phase with the polar jet and create monsters - President's Day Snowstorm II in 2003 was a good example.
Tornadoes, since a strong Nino keeps things progressive due to its jet, and prevents huge intrusions of cold air in the east, a strong Nino can bring hoards of outbreaks in the southern U.S. (1998 was a good example). But the cold east during weak/mdt ninos don't support this.
Hurricanes, subtropical jet = shear over Atlantic. Inverse relationship between Atlantic and EPAC, so EPAC heats up. In addition warmer waters in Pacific promote stronger convection and thus more TC's, from the eastern WPAC to the EPAC. Effects in the tropical cyclone can vary and the difference here between weak and strong Nino is pretty insignificant.