Wanda could still form in the middle the Atlantic over the weekend
The big former nor’easter is still producing winds over 40 mph over the open Atlantic well off the Northeast coast. In non-tropical parlance, winds over 40 mph are called gales. If the system were to evolve into Wanda – a technical meteorological distinction – we would call them tropical-storm-force winds.
The low-pressure system is still connected to fronts, which are producing elongate areas of stormy weather. One of the important distinctions between tropical and non-tropical systems is that tropical systems exist on their own with no connected frontal systems. It’s not clear if that’s going to happen with this storm or not.
According to the computer forecast models, there seems to be a chance of the system meeting the criteria to be named Wanda about Sunday as it sinks south over marginally warm-enough water. Normally, we say the ocean temperature has to be 80 degrees for a tropical system to get going, but that’s not true in the North Atlantic. Because the atmosphere aloft is cool, the contrast with water in the 70s can sometimes do it. That seems to be the case with wannbe-Wanda.
The National Hurricane Center is giving the system a fairly low chance of pulling this off. In any case, the naming is only important for the record books. The storm, whether it’s named or not, will move out to sea.
Nine years ago this evening, Superstorm Sandy made landfall on the Northeast coast. The center of the giant circulation came ashore near Atlantic City, New Jersey. But, of course, the impacts extended far to the north including the entire New York City region.
Sandy was a super-unusual hybrid storm. A hurricane from the south got absorbed into an intense northern system so it was essentially a hurricane embedded in a giant nor’easter. The hurricane was being powered by the warm Gulf Stream water, while the nor’easter wrap was powered by the cold- and warm-air contrast around the storm.
As Sandy moved north, the water cooled, and the hurricane’s energy transferred into the non-tropical nor’easter. It was that combo system that came ashore.
At the Weather Channel, we name it Superstorm Sandy as soon as it made its transition to a non-tropical system. We thought its official name, Post Tropical Cyclone Sandy, did not convey the seriousness of the continuing threat. The system was indeed “post-tropical,” in the sense that it wasn’t tropical any longer. But the word “post” also conveys that an event is over.
Sandy was, obviously, far from finished. Appropriately, the name Superstorm Sandy stuck.
Fortunately, this year, there are no late-season surprises in the works, at least for the next week. Odds are very low, but not zero, that something could still develop this season in the southern Caribbean. So we’ll keep half an eye on that.