Is the recent tropical activity in the Pacific an indication of a strengthening El Nino? This is a very important weather question.
The key to the weather across the United States in the upcoming winter is the strength and duration of the current El Nino. In fact, some of the winter 2009-2010 forecasts are based, at least in some degree on the El Nino, and I’ve recently written that the lack of strengthening of the El Nino (El Nino Weak–What Does it Mean?) means that these forecasts are in jeopardy.
I might have spoken too soon.
Central Pacific Hurricane
Hurricane Rick, which occurred during the middle of the month, was the second strongest hurricane in the Pacific basin, but it occurred in the eastern Pacific, away from the center of the El Nino. The activity in the central Pacific (closer to Hawaii) is what might be an indication of warming water in the El Nino zone.
This satellite image from the Central Pacific Hurricane Center (linked above) is an indication of recent activity.
Central Pacific Hurricane Center satellite image from October 23, 2009
Hurricane Neki formed to the south of Hawaii and moved northward over the past couple of days, bypassing Hawaii to the west (unlike the devastating Hurricane Iniki in 1992, which occurred during an El Nino). As of Friday afternoon, there was a cluster of thunderstorms to the southeast of Hawaii as well–an area of disturbed weather that will need to be monitored.
Hurricanes are driven by warm water, and if the recent activity is an indication of warming water in this region, then the El Nino might finally be showing the strengthening needed to influence the weather across the United States this winter.
I’ll have an update on El Nino in early November.
–Paul Yeager
