This Year’s El Niño

From the U.S. National Weather Service (NWS):

This year’s El Niño, among the strongest on record, is expected to influence weather and climate patterns this winter by impacting the position of the Pacific jet stream. Forecasters at NOAA’s Climate Prediction Center favor cooler and wetter weather in Southern Tier states with above-average temperatures most likely in the West and across the Northern Tier. 

El Niño is an ocean-atmospheric phenomenon marked by warmer-than-average sea surface temperatures in the central and eastern Pacific Ocean near the equator, which occur on average every 2-7 years and last about 9-12 months. The presence of El Niño can influence global weather, climate, ocean conditions, and marine fisheries.

Forecast: http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.html
Winter Outlook: http://www.noaanews.noaa.gov/stories2015/101515-noaa-strong-el-nino-sets-the-stage-for-2015-2016-winter-weather.html
Typical Impacts of El Niño: https://www.climate.gov/news-features/blogs/enso/how-enso-leads-cascade-global-impacts