To state the obvious, this has been an unorthodox Atlantic hurricane season.
All by the US agency most devoted to the study of the weather, oceans, and atmosphere – the National Ocean and Atmospheric Administration highly respected hurricane experts predicted a season of above-average to well above-average activity.
For example, the NOAA Outlook for the 2022 Atlantic hurricane season, which lasts June 1 through November 30, projected a 65 percent chance of an above-average season, a 25 percent chance of a near-normal season, and a 10 percent chance Percent for a below normal season. The main factor behind these predictions was the expectation that La Niña would persist in the Pacific Ocean, resulting in atmospheric conditions in the tropical Atlantic being more favorable for storm formation and intensification. La Niña has held up, but the storms still haven’t come in clusters.
To date, the Atlantic has had five named storms, which is not too far from “normal” activity based on climatological averages from 1991 through 2020. Normally, the Atlantic would have recorded eight tropical storms and hurricanes by now, given names by the National Hurricane Center.
The discrepancy is more significant when we look at a metric of storm duration and intensity known as Accumulated Cyclone Energy. With this more meaningful measurement, the 2022 season has a value of 29.6, which is less than half of the normal value up until Saturday, 60.3.
Perhaps the most striking thing about this season is that we are now at the absolute peak of hurricane season and just nothing is happening. Although the Atlantic season starts on June 1st, it starts slowly, with maybe a storm here or there in June and often a calm July before the deep tropics get rolling in August. Typically, about half of all activity occurs in the 14 weeks leading up to September 10th, and then the vast majority of the remaining storms turn up in a frenzied, boisterous rush before the end of October.
While it’s still entirely possible that the Atlantic Basin — which includes the Atlantic Ocean, the Gulf of Mexico, and the Caribbean Sea — is producing an insane finish, we just don’t see any signs of it right now. There are currently no active systems and the National Hurricane Center is only tracking a tropical wave that will move from the African coast into the Atlantic in the coming days. It has a relatively slim chance of development and none of the global models expect much from the system. Our best global models show a 20 to 30 percent chance of a tropical depression developing somewhere in the Atlantic over the next 10 days.
This is exactly the opposite of what we usually see at this time of year when the tropics are usually lit up like a Christmas tree. This is because September offers a window when the Atlantic is still warm from the summer months and we typically see some of the lowest wind shear readings in storm-forming regions.
What went wrong
So what happened this year to cause a quiet season, at least so far? A detailed analysis will have to wait until after the season, but so far we’ve seen a lot of dust in the atmosphere that has stifled storm formation. Additionally, upper-level atmosphere winds were generally hostile to storm formation – essentially shearing off the top of all developing tropical systems.
While it looks like the 2022 seasonal forecasts are likely to be blown, it’s important to understand the difference between this activity and forecasting actual storms. Seasonal forecasting is still an evolving science. While it’s usually more right than wrong, predicting specific weather patterns like hurricanes months in advance is far from established science.
In contrast, forecasters have made tremendous strides in predicting the tracks of tropical storms and hurricanes that have already formed. And although not as clearly, our ability to predict an intensification or weakening has also improved. Since Hurricane Andrew in 1992, the most destructive storm to ever hit Florida, the National Hurricane Center’s track forecast accuracy has been accurate got better by 75 percent and his intensity forecast by 50 percent.
This is due to several factors, including more powerful supercomputers capable of processing higher-resolution prediction models, a better understanding of the physics of tropical systems, and better tools for collecting real-time data on atmospheric conditions and feeding that data into prediction models quickly.
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