Laurissa Anyas-Weiss, content producer
August 18, 2009 — It's official, El Niņo is here and is beginning to impact our weather. The big question is how much will it impact us in Canada.
On August 6, 2009, the National Oceanic and Atmospheric Administration (NOAA) in the US issued a statement confirming that a weak El Niņo was present during July when monthly sea surface temperatures ranged from +0.5 to +1.5 degrees warmer across the equatorial Pacific Ocean. Other oceanic and atmospheric anomalies also support the presence of El Niņo.
NOAA's models forecast El Niņo to strengthen while there is some disagreement as to its eventual strength. A weak-to-moderate El Niņo developed through the fall and models predict a moderate-to-strong El Niņo during the Northern Hemisphere Winter 2009-10.
2009 Hurricane Season
El Niņo's impact was felt in the fairly quiet 2009 Atlantic Hurricane Season. On the same day it announced the presence of El Niņo, NOAA revised its Hurricane Season Outlook reducing the likelihood of an above-normal hurricane season from 25% to 10%. In the end, there were only 9 names storms in the Atlantic compared to the average of 15. For Canadians it was not a season without storms as Bill, Danny and the remnants of Hurricane Ida hit Eastern Canada.
While the Atlantic storm season was quiet, the 2009 Pacific Hurricane Season was unusually active. The El Niņo effect warms up the Pacific waters which may have contributed to the 20 names storms this season including Hurricane Rick a category 5 storm.
El Niņo in Canada
A weak El Niņo makes seasonal forecasting difficult as we saw this summer. Early indications called for a warmer than normal summer for parts of Eastern Canada whereas for most people in the East, the month of July felt cooler than normal.
Strong El Niņos are more predictable and often result in milder winters in the East while in the West, spring and summer are drier. During an El Niņos winter (see diagram on left) the Polar Jet stream rides higher in the west hence bringing warmer temperatures.
Winter Games 2010
The Winter Outlook is calling for an El Niņos winter across Canada. In the West, temperatures will be warmer than normal with near normal precipitation. Could this be an issue for the Winter Games in Whistler? Warm moist air from the Pacific is the opposite of what snow machines would need i.e. cool and dry air. On the other hand, this does potentially place them on the storm track where they could have a nice natural snow maker! Recent heavy precipitation in BC has meant flooding on the coast but lots of snow for Whistler.