Risk of Seasonal Climate Extremes in the U.S. Related to ENSO

Updated September 2015 to include 20 more years, and the extended Multivariate ENSO Index to define ENSO events.

Extremes of temperature and precipitation can occur at any time. However, it can be shown that the El Niño/Southern Oscillation has a relationship to the relative frequency of these seasonal climate extremes in the United States. To see which regions of the U.S. have an increased or decreased risk of extreme warm/cold (or dry/wet) seasons during an ENSO event, select from the options below. Note that these changes in ENSO-related climate risk vary not only by region, but also by season.

Important: These plots show regions where the risk of having a seasonal extreme is higher than expected. If you would like average values of temperature and precipitation during El Niño/La Niña, you should look at ENSO composite plots.

Select type of ENSO event, temperature or precipitation and season to show the relative risk of climate extremes based on concurrent value of the ENSO index (MEI.ext) for the continental United States:

Type of ENSO Event:   El Niño   La Niña
Variable: Temperature    Precipitation
Risk Type: Increased Risk    Decreased Risk

Current ENSO State

Method Details

This page is based on work-in-progress by Klaus Wolter, Jon Eischeid, Randy Dole, Robin Webb, and Cathy Smith of the NOAA/ESRL Physical Science Division. It replaces an earlier version that used data from 1896-1995 and was described in Wolter et al. (1999). You can use these plots in publications though we ask that you acknowledge the Physical Science Division in the publication. For example, "Image provided by the NOAA/ESRL Physical Science Division, Boulder, Colorado, from their web site at: http://psl.noaa.gov/enso/climaterisks".

Related Web Pages:


  • Wolter, K., R. M. Dole, and C. A. Smith, 1999: Short-Term Climate Extremes over the Continental United States and ENSO. Part I: Seasonal Temperatures. J. Climate, 12, 3255–3272. doi: http://dx.doi.org/10.1175/1520-0442(1999)012<3255:STCEOT>2.0.CO
  • Wolter K. and M. S. Timlin (June 2011): El Niño/Southern Oscillation behaviour since 1871 as diagnosed in an extended multivariate ENSO index (MEI.ext). Int. J. Climatol., 31 (7), 1074-1087. doi:10.1002/joc.2336
  • Wolter, K., and M.S. Timlin, 1993: Monitoring ENSO in COADS with a seasonally adjusted principal component index. Proc. of the 17th Climate Diagnostics Workshop, Norman, OK, NOAA/NMC/CAC, NSSL, Oklahoma Clim. Survey, CIMMS and the School of Meteor., Univ. of Oklahoma, 52-57. Download PDF.
  • Physical Sciences Laboratory ENSO References

Any comments, suggestions or questions on this page are welcome and should be sent to psl.data@noaa.gov

This is a Research and Development Application