Hurricane Season to Continue on Pause for a While

The atmosphere over the Tropical Atlantic continues to be hostile to tropical development. High pressure, which is often sprawled across the Atlantic, has persistently nosed well into the Gulf. That high has blocked any tropical systems from turning north and caused persistent dry weather across Florida.

Occasional disturbances have moved off Africa and through the tropical moisture belt south of the high-pressure system, as we expect this time of year. But the unusual breadth and strength of the high has directed systems with the potential to develop to the Eastern Pacific. Two storms have already formed and another is likely.

The second factor keeping the Atlantic quiet is Saharan dust. The flow around the high-pressure system has opened a persistent channel for the dusty air to spread west into the Caribbean and occasionally to Florida and into the Gulf.

The ocean water temperatures across the tropical Atlantic between the Caribbean and Africa have returned to normal this year after two years of being extremely warm. That means that, unlike last year, no storms are unlikely to form east of the Caribbean until the water warms up later in the hurricane season.

Water temperatures in the Caribbean Sea and the southern Gulf are always warm enough for tropical development, and this year they are even warmer than normal. A disturbance has to trigger a system to organize, however, and the dust and the storm track into the Pacific have kept the lid on any development.

Computer forecast models, including the new AI models, are showing a slight chance that something might develop in the far western Gulf next week, but the chances are very low. Until the sprawling high-pressure system breaks down, tropical development is unlikely.

The odds favor the Atlantic staying quiet through next week, at least.

The delayed start to the hurricane season is not unusual. About a third of the time since 1950, the first Atlantic storm was named after June 15. And it's important to note that the eventual busyness of the hurricane season is not related to how it starts.

In 2004, which was a gangbuster year with four hurricanes impacting Florida, the first storm to get a name in the tropics was Bonnie, and that wasn't until August 9. Alex formed on August 1, but in the far North Atlantic. So that wasn't related to the season's tropical developments.

All indications are that this hurricane season will get busy once it gets going. Researchers at Colorado State University updated their seasonal prediction today but did not change their numbers from their April forecast. They are still calling for 17 named storms, 9 of them hurricanes, with 4 of them reaching Category 3 or above.

Hurricane season forecasts are issued by a variety of companies and agencies around the world. They all predict a similar outcome to the CSU numbers - average to slightly above average activity. But the CSU team acknowledges that the forecast is more uncertain this year than normal. If the tropical Atlantic warms up before the peak of the season, or a hurricane-supporting La Niña develops in the Pacific this fall, none of us will be surprised.

For now, enjoy the pause.