JACKSONVILLE, Fla. – When tropical storms slow down or stall, they can cause a lot more damage. Think heavier rain, bigger storm surges, and longer periods of strong winds. Stalling happens when a storm stays in one spot for a while, and that’s when things can get really bad.
Researchers looked at storms in the North Atlantic from 1900 to 2020 and found that about 15% of them stalled at least once. They define a stall as a storm staying within a 124-mile area for 72 hours. One example is Hurricane Ginger in 1971, which stalled four different times.
A map highlighted in the September Journal of Applied Meteorology and Climatology shows stalls concentrated east of Florida and Georgia more frequently during May, June, and July.
Stalls are more frequent throughout the Gulf and Atlantic basins in September (n=71) and in the Western Caribbean by October (n=55). October has more stalled storms in the Caribbean Sea than any other month.
What’s interesting is that stalling has been happening more often since the satellite era started in 1966, going up by 1.5% every year.
Plus, when storms stall, they’re more likely to turn into major hurricanes, especially when they’re near the coast. Almost 40% of these stalling storms got stronger quickly, sometimes right before hitting land.
Tropical storms slow down or “stall” when the winds guiding them are weak or when winds at different levels of the atmosphere move in opposite directions. Scientists believe that as the planet warms, tropical storms may move more slowly, leading to an increase in stalling storms. This is because warming causes changes in the atmosphere, such as weaker winds and less movement for storms, allowing them to stay in one spot for longer.
Stalling storms often last longer than fast-moving ones, especially stronger storms like Category 3 hurricanes. These slow-moving storms can take longer to weaken because they don’t move as quickly into areas that make them lose strength, like land or colder regions.
However, since they stay over warm ocean water longer, they can pull energy from the ocean and intensify quickly. Almost half of the storms that rapidly intensified did so near the coast, making them especially dangerous.
This research helps inform where and when storms are likely to stall, which can help people prepare better for future storms.