Severe storm outlooks for March, April and May, photo credit Climate.gov
Spring 2016’s El Niño Remnants May Affect Tornadoes in the US. Every season and every El Niño are unique but meteorologists are able to make some basic assessments of how such events may affect tornado output based on prior observations. Several factors drive weather, so the higher temperatures in the Pacific related to El Niño can’t be used to directly deduce tornadic threats; however, they may give clues about the upcoming general weather pattern over a specific period.
The water temperatures from the present El Niño peaked in mid-November but were still well above average in January. The characteristic tongue of warm water that touches northwestern South America began to recede to the central Pacific but some of the implications of the recent warming will linger throughout Spring.
2016’s first major tornado outbreak happened in the last week of February, spawning over 40 as it pushed across the south and east. The first week of March has been quiet but week 2 is projected to intensify.
Generally speaking, March and April are typically wetter in the eastern United States after El Niños. Although sufficient moisture is a necessary ingredient in a tornadic system, absences of some of the other necessary ingredients can still inhibit their formation. El Niño tends to suppress overall tornadic activity in the US but tends to favor it farther southward than seen during average conditions. All of Florida’s major tornado outbreaks have occurred during El Niño years. California also tends to endure more.
The second annual March-May severe weather forecast is predicting fewer tornadoes and hail than average. A 54% chance has been suggested for tornado output to be below normal, with a 39% chance of normality. The forecast also predicts a 71% chance of fewer hailstorms than normal, with a 27% chance of normality.
A transference to La Niña, a reversal of El Niño’s characteristic cyclical pattern, is expected to come this fall. The transition notoriously increases the threat of tornadoes in the US. This might make for an interesting season next year.
Article written by Meteorologist Geoff Linsley