What's going on with this year's hurricane season?
While things have started to change recently, the 2022 Atlantic hurricane season – which runs from June 1st to November 30th – has been abnormally quiet.
In fact, the Atlantic went through all of August without a hurricane. That’s very rare – it has only happened seven times since 1950. The last time it happened was in 2013 according to Phil Klotzbach – a research scientist who works on hurricane projections at Colorado State University.
Meteorologists were expecting this year’s season to be an active one. On average, the Atlantic typically sees about 14 named storms, seven hurricanes and three major hurricanes. CSU was projecting nine hurricanes and four major ones (that’s Category 3 or higher) before the season began.
La Nina conditions were projected to help bolster that active season. That’s a global weather pattern that typically results in lower wind shear in the Atlantic basin – especially in the main development region says Stephanie Zick, a hurricane expert at Virginia Tech.
The water in the Atlantic is also very warm – which is beneficial to hurricane development.
So, what gives? With all of those factors, this year’s season should have developed more hurricanes.
Zick says this year has been unusual. La Nina conditions are present, but wind shear in the Atlantic hasn’t dropped off as much as anticipated. But, that’s not the primary factor.
“The major reason that we haven’t had many systems is because there is a lot of dry air.”
She adds that tropical waves – the precursor to tropical systems – were moving across the Atlantic earlier this summer before encountering that dry air that stymied any further development.
But, Zick says things are starting to shift. Two named storms earlier this month – Danielle and Earl – may pave the way for others to form.
“What happens is – so those systems move through and they kind of like move moisture up vertically and mix moisture up into the atmosphere. And that would make it more favorable for future development of future storms.”
She expects the rest of September to be more active.
Overall, though, Zick predicts this year’s season will go down as average or below-average as far as the number of named storms.
“But that doesn’t mean that it won’t be impactful. There’s still a lot of favorable conditions for these storms. And especially sea surface temperatures are very, very warm – they’re warmer than average. And they’re warmer than average close to land – so warmer than average in like the Gulf of Mexico and the Caribbean. So, they’re warmer close to these land masses, so any storms that form that move over these waters have the potential to intensify rapidly. And so, we need to keep watching that.”
The National Hurricane Center issued the first advisory for a new tropical depression Wednesday morning. It could impact portions of the Virgin Islands and Puerto Rico heading into the weekend. But otherwise, NHC isn't monitoring any other potential areas of development.
Zick adds that researchers are learning more about rapid intensification of these storms – and forecast models are getting better at predicting that. Meteorologists also have a much better understanding of the impacts of vertical wind shear on hurricanes than they used to.
But, tropical system formation still puzzles researchers.
“We don’t have a great understanding of why one tropical wave develops and another tropical wave doesn’t. So sort of discriminating between a developing wave and a non-developing wave. We just don’t have a great understanding of that.”
That’s why continued research – like that conducted by Zick – is so important. She says heavy rain from tropical systems has caused more deaths and property damage over the last 10 years or so.
“We want to be able to forecast these storms better so that people can be better prepared to protect their lives and property.”