Owner system

It’s been four weeks since the last named Atlantic tropical system, but peak season is fast approaching

Editor’s note: A version of this article originally appeared in the weekly weather report, the CNN Weather Brief, which is published every Monday. You can sign up here to receive them weekly and during major storms.



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We have now entered the third month of hurricane season, which is over 30% of the way there, and it looks like we are getting off to a slow start. People even asked me where it was, or even said they thought this season was supposed to be busy.

So, I asked a hurricane expert.

“You’re right! It’s sure been quiet in the Atlantic lately,” Colorado State University researcher Phil Klotzbach said in an email to CNN. late June/early July with Bonnie and Colin, but it’s been dead since.”

And you may not even remember those two storms, especially Colin in early July. If you blinked, you missed it. Colin formed on land in South Carolina and only survived about 24 hours.

But let’s not write hurricane season yet. If you have vacation plans over the next two weeks, you should be clear – however, we should start to see things slowly (or quickly) changing soon.

“There are signs that things should improve as we head into mid-August,” Klotzbach noted.

One of the reasons we had a calm few weeks was the dry air coming in from Africa.

“This dry air suppresses the storm activity that is needed for storm complexes moving out of Africa to develop and develop into hurricanes,” Klotzbach explained. “Dry air is quite common in the tropical Atlantic at this point in the season.”

Often outbreaks of dry air are associated with the Saharan dust that you hear us talk about a lot at this time of year. Dry air carries dust across the Atlantic and can reach the United States. It can cause respiratory problems for some but also provide bright sunsets and sunrises.

“Typically, by the time we get to mid-August, heavy dust outbreaks (and associated dry air) tend to subside, and the tropical Atlantic becomes more conducive to hurricane formation. “, added Klotzbach.

It’s also easy to lose sight of what’s even considered normal now. 2020 and 2021 have been extremely active seasons at the start. 2020 had 30 named storms for the entire season and was already on named storm I (Isaias) at this point in the season, running through the entire alphabet and part of the Greek alphabet as well.

Last year exhausted all hurricane names for the second year in a row, which had never happened before, and marked the sixth straight “above normal” hurricane season.

Homes in Grand Isle, Louisiana destroyed during Hurricane Ida in August 2021.

So it’s no surprise that we’re starting to wonder why nothing has happened over the past few weeks. But 2021 also saw a small break during this period, where nothing formed between July 9 and August 11, which is very reminiscent of this year.

Klotzbach also pointed out that while El Niño and La Niña are big seasonal drivers of how the season unfolds, there are other phenomena that cause shorter-term variability.

“The Madden-Julian Oscillation can either increase or decrease hurricane activity in the Atlantic,” Klotzbach pointed out. “The MJO is deep thunderstorm activity that travels around the globe approximately every 30 to 60 days. In doing so, it can alter vertical wind shear and mid-level humidity levels.

This was another contributing factor to the lack of activity over the past month as the oscillation barred the development of thunderstorms over Africa.

Thunderstorms in West Africa tend to push westward into the Atlantic, becoming the building blocks of tropical development.

Although this month has been a nice break from the hurricanes, Klotzbach is confident the tide will turn.

“Models generally predict a more favorable pattern for the Atlantic by mid-August,” Klotzbach reported. “The air is expected to rise more steadily over Africa and sink over the tropical Pacific. This pattern should result in a reduction in vertical wind shear.

This means that we will see an environment conducive to the development of hurricanes, just at the right time.

“The first medium Atlantic hurricane forms on August 11 and historically 90% of major hurricanes form after August 20,” Klotzbach said.

The National Oceanic and Atmospheric Administration and Colorado State University both release their updated hurricane forecasts for the season on Thursday, so be sure to check back and see if the numbers are rising, falling, or staying the same.

Additionally, Vice President Kamala Harris is traveling today to the National Hurricane Center in Miami, where she “will receive a briefing on climate resilience as communities face climate risks including hurricanes, floods, drought, extreme heat and wildfires,” according to the White House Schedule.