Science

ENSO in 2014
The El Niño Southern Oscillation is an irregular cycle in which changing temperatures of surface waters in the tropical Pacific Ocean can result in major impacts on global weather patterns.
ENSO in 1997 and 1998
The 1997-98 El Niño event stands out both for its intensity and how it brought the ENSO phenomenon to public attention.
Ice skaters in Madison
Each El Niño event has a different effect on weather conditions on both global and local scales. These differences in large part depend on how a given El Niño develops.
ENSO 2015 forecast
The current El Niño is on track to be one of the strongest recorded. Indicators of a strong cycle have been increasingly documented over much of 2015 and continued to mount into autumn.
ENSO impact in North America
While the ENSO cycle is unpredictable, climatologists have identified consistent weather patterns during strong El Niño and La Niña years since the 1950s.
ENSO cycle map
The weather phenomenon most commonly called El Niño is one part in a cycle of irregularly changing trade winds and sea surface temperatures in the equatorial Pacific Ocean.
Winter tundra along ice age trail
Much of Wisconsin is experiencing a very warm autumn so far, with temperatures higher than average in both September and October. One factor that might be influencing these balmy conditions is El Niño, a recurring global weather pattern that can result in warmer winters for Wisconsin.
Lake Mendota
Whether looking forward to ice fishing season, crossing fingers for a rare journey to Lake Superior's sea caves on the shores of Bayfield County or just enduring the long cold months of winter, chances are the dates that lakes freeze and thaw are one mark by which one can measure the season in Wisconsin.
The Weather Guys
The "polar vortex" that memorably descended over Wisconsin starting in January 2014 wasn't really all that bad, at least when considered in the context of 66 years of weather data for the Northern Hemisphere's lower troposphere (that is, one mile above the ground).
David Liebl
Wisconsin's climate is gradually warming and is forecast to get warmer by the mid-21st century. Climatologists track this regional reflection of a planetary trend in large part through a series of satellites that gather data about Earth's lands, seas and air, and subsequently, use this information to help model long-term climate projections.