1. Impacts of La Niña (and NAO) on Washington DC Winters Winter Media Workshop 12/9/2011 Jared Klein LWX Climate Program Leader

2. NOAA/CPC 2011-12 Winter Outlook (Updated outlook- mid November) Temperatures Precipitation The seasonal outlooks combine the effects of long-term trends, soil moisture, and, when appropriate, ENSO.

3. Current State of ENSO http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/

4. Current State of ENSO (cont.) http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/

5. The majority of ENSO models predict the continuation of a weak to moderate La Niña at least through the Northern Hemisphere winter. ENSO Forecast International Research Institute (IRI) for Climate and Society

6. http://www.cpc.noaa.gov/ products/analysis_monitoring/ensoc ycle/nawinter.shtml El Niño pattern that dominated the 2009-10 winter La Niña pattern that dominated last winter and so far this fall

7. http://www.cpc.noaa.gov/ products/analysis_monitoring/ensoc ycle/nawinter.shtml El Niño pattern that dominated the 2009-10 winter La Niña pattern that dominated last winter and so far this fall

8. La Niña Winters and Temperature

9. 1981-2010 Normal DJF Temp- 38.2°F La Niña Averages La Niña Time Series

10. La Niña Winters and Precipitation

11. 1981-2010 Normal DJF Precip- 8.48" 1981-2010 Normal DJF Precipitation (8.48”) La Niña Averages La Niña Time Series

12. La Niña Winters and Snowfall

13. La Niña Averages La Niña Time Series 1981-2010 Normal Seasonal Snowfall - 15.5" 1981-2010 Seasonal Snowfall (15.5”)

14. 1 1- 56.1” (09-10) 2 2- 46.0” (95-96) 3 3- 40.4” (57-58) 3 3- 40.4” (02-03) 5 5- 40.3” (60-61) 6 6- 37.7” (78-79) 7 7- 37.1” (66-67) 8 8- 33.6” (63-64) 9 9- 31.1” (86-67) 10 10- 28.4 ” (65-66) 11 11- 27.6” (82-83) 12 12- 25.0” (87-88) 13 13- 24.3” (59-60) 14 14- 22.7 ” (77-78) 15 15- 22.5” (81-82) 16 16- 21.4” (62-63) 16 16- 21.4” (67-68) 18 18- 20.1 ” (79-80) 19 19- 18.0” (53-54) 20 20- 17.1 ” (64-65) 21 21- 16.8” (71-72) 22 22- 16.7” (73-74) Years with Above Normal Snowfall at DCA (>15.5”) since 1950 +3 SD +2 SD +1 SD

15. Assessment on the 2009-10 Winter NOAA Attribution Team (Hoerling et al. 2010) 500 mb height anomalies from the 30 snowiest months at Washington DC -NAO

16. Questions/Comments? Jared.Klein@noaa.gov