(Hybrid Monster Sandy Bears Down on US East Coast)
According to reports from NOAA, an ‘extremely active’ hurricane season lies on the horizon just one year after an unprecedented and freakish hybrid hurricane Sandy devastated the US East Coast.
Overall, forecasters expect between 13 and 20 named storms with 3-6 major hurricanes potentially in the offing. The average season hosts 12 named storms. So these numbers may well be harbingers for a dangerous year.
“With the devastation of Sandy fresh in our minds, and another active season predicted, everyone at NOAA is committed to providing life-saving forecasts in the face of these storms and ensuring that Americans are prepared and ready ahead of time.” said Kathryn Sullivan, Ph.D., NOAA acting administrator. “As we saw first-hand with Sandy, it’s important to remember that tropical storm and hurricane impacts are not limited to the coastline. Strong winds, torrential rain, flooding, and tornadoes often threaten inland areas far from where the storm first makes landfall.”
This is a dire forecast, especially coming one year after Sandy. Usually, natural variation will bring a pause in activity after years involving powerful storms. However, the Northeast US has suffered two major storms in two years. Now, forecasters are calling for yet another year where powerful storms threaten US shores.
Conditions for powerful storms come from a number of factors. The first is that Atlantic Ocean water temperatures remain well above average in most regions. African dust, which tends to suppress storm development, is less and less prevalent. ENSO conditions in the Pacific remain neutral — La Nina tends to enhance Atlantic storm development while El Nino tends to suppress it. All these conditions point toward a more active year.
One factor not taken into account for current official forecasts is the present state of the polar jet stream. That said, meteorologists and climatologists have been presented with quite a lot to chew on as a new hurricane season emerges under a regime of rapid Arctic changes. Erosion of sea ice has resulted in greater dips in the jet. The result is that polar frontal systems are more likely to encounter tropical systems steaming northward. As such, the formation of storms similar to Sandy becomes more likely. With sea ice values low and going lower, it appears that the next few years will serve as a test to determine if this entirely new atmospheric state will result in a greater number of these powerful hybrid storms.
The atmospheric basis for the formation of such storms, however, is already in evidence with powerful alterations to the polar jet resulting in a severe winter in Europe and abnormal warmth for the US west coast and western Canada. Let’s hope these dips don’t line up in such a way as to make polar and tropical storms meet again as they did last fall.