Why Some Hurricanes Stall Instead of Moving Forward

Sixty inches of rain. That's what parts of the Houston area got from Hurricane Harvey in 2017 — not because the storm was unusually powerful when it made landfall, but because it barely moved for four straight days. Hurricane Dorian did something similar in the Bahamas in 2019, grinding forward at one mile per hour at its slowest, battering Grand Bahama with a storm surge of up to 23 feet for the better part of two days. Neither storm needed record wind speeds to become a historic disaster. They just needed to stop.

Why do hurricanes stall instead of moving forward?

A hurricane doesn't steer itself. It gets carried along by the broader wind patterns around it — what meteorologists call the atmospheric flow — the same way a leaf gets carried by a stream. Fast currents move it fast; weak or conflicting currents barely move it at all. In the Atlantic, a lot of that steering comes from the Bermuda high, a persistent zone of high pressure that pushes many storms along their typical curving path out to sea or into the U.S. coast.

When a storm gets caught between competing flows, or when the steering currents around it simply go slack, its forward speed can drop to a crawl. At that point even small errors in a forecast model's starting data get amplified into large differences days out — one reason Kimberly Wood, an assistant professor of meteorology at Mississippi State University, has written that slow-moving storms are disproportionately hard to forecast: when the steering wind itself is only moving five miles an hour, a two-mile-an-hour difference in the model's initial read is a much bigger deal than it would be inside a fast-moving current.

Is climate change making hurricanes stall more often?

The research points that direction, though scientists are careful about how far to take it. A study led by NASA and NOAA scientists, published in the journal npj Climate and Atmospheric Science in June 2019, found that the average forward speed of North Atlantic hurricanes dropped 17 percent between 1944 and 2017 — from 11.5 mph down to 9.6 mph. The suspected culprit is a broader slowdown of global atmospheric circulation, tied in part to the Arctic warming roughly twice as fast as the mid-latitudes, which narrows the temperature contrast that drives a lot of the wind patterns steering these storms in the first place.

"Stalling hurricanes wreak much more havoc than those that blow through quickly," Tim Hall, a hurricane researcher at NASA's Goddard Institute for Space Studies and an author of the study, told Inside Climate News in 2019. "Dorian definitely fits the pattern that we found in our paper." NOAA hurricane scientist Jim Kossin, who co-authored the study, put the broader mechanism this way: "In the broadest sense, global warming makes the global atmospheric circulation slow down."

Not every climate scientist treats the connection as settled. Penn State's Michael Mann has said the stalling trend is real but that pinning down exactly how much of it traces to climate change specifically "is really at the leading edge of the science and is still being debated" — because the computer models used to project future climate can't yet fully capture the atmospheric changes that would cause storms to slow down.

Why does a slow storm cause more damage than a fast, intense one?

A hurricane threatens land three separate ways: wind, storm surge and rainfall. Wind and surge are largely a function of the storm's intensity when it arrives. Rainfall is a function of both intensity and how long the storm parks over one place. A slower storm keeps dumping rain on the same river basins and neighborhoods instead of spreading the load across a wider path, and warmer air holds more moisture to begin with — every degree of ocean and atmospheric warming gives a storm more water vapor to convert into rain, the same basic physics behind why a humid heat wave feels worse than a dry one at the same temperature.

Hurricane Florence showed how that combination compounds in 2018, pushing a 10-foot storm surge into North Carolina's Neuse River at the same time it dropped more than 20 inches of rain across the state — inland flooding meeting storm surge coming the other direction, in areas that don't expect to flood from either alone.

What's the mechanism this year?

The 2026 Atlantic hurricane season has been unusually quiet so far — among the slowest starts in over a decade, with an emerging El Niño pattern working against storm development in the tropics. That's a separate factor from stalling; a quiet season doesn't mean this year's eventual storms, if and when they form, will move any faster once they do. The mechanics of what makes a hurricane stall — weak or conflicting steering currents, a stubborn ridge nearby, an atmosphere carrying extra moisture — don't depend on how many storms have formed already.

For anyone watching a storm approach the coast, the practical lesson from Harvey, Dorian and Florence is the same one meteorologists keep repeating: category number tells you about wind. It tells you almost nothing about how long a storm plans to stay.