Tropical Storm Margot formed Thursday in the North Atlantic Ocean, becoming the 13th named storm of the 2023 Atlantic hurricane season.
The National Hurricane Center estimates the storm had sustained winds of 40 miles per hour and would most likely develop into a hurricane by the weekend, but posed no immediate threat to land. The tropical disturbances that sustained winds of 39 mph deserve a name. Once winds reach 74 mph, a storm becomes a hurricane, and at 111 mph it becomes a major hurricane.
Margot is currently one of two active tropical cyclones in the Atlantic. Hurricane Lee upgraded to a Category 4 storm Thursday afternoon, according to the Hurricane Center.
The Atlantic hurricane season started on June 1 and will continue until November 30.
In late May, the National Oceanic and Atmospheric Administration predicted there would be between 12 and 17 named storms this year, a “near-normal” number. On August 10, NOAA officials revised their estimate up from 14 to 21 storms.
There were 14 named storms last year, following two extremely busy Atlantic hurricane seasons in which forecasters ran out of names and had to resort to backup lists. (A record 30 named storms occurred in 2020.)
This year we present an El Niño pattern, which arrived in June. The intermittent weather phenomenon can have far-reaching effects on weather patterns around the world and generally curbs the number of hurricanes in the Atlantic.
In the Atlantic, El Niño increases wind shear, which is the change in wind speed and direction from the ocean or land surface to the atmosphere. Hurricanes need a calm environment to form, and the instability caused by increased wind shear makes these conditions less likely. (El Niño has the opposite effect in the Pacific, reducing wind shear.)
At the same time, rising sea surface temperatures this year pose a number of threats, including the ability to cause storms.
This unusual confluence of factors has made robust forecasts of storms more difficult.
“Things just don’t look good,” said Phil Klotzbach, a hurricane researcher at Colorado State University, after NOAA released its updated forecast in August. “There are just a lot of weird things that we haven’t seen before.”
There is a strong consensus among scientists that hurricanes are becoming more powerful due to climate change. While there may not be more named storms overall, the likelihood of major hurricanes increases.
Climate change also affects the amount of rain that storms can produce. In a warming world, the air can hold more moisture, which means a named storm can hold and produce more precipitation, like Hurricane Harvey did in Texas in 2017, when some areas received over 40 inches of rain in less than 48 hours.
The researchers also found that the storms have slowed down and persisted longer in some areas over the past few decades.
As a storm slows above water, the amount of moisture it can absorb increases. When the storm slows down over land, the amount of rain that falls in one place increases; in 2019, for example, Hurricane Dorian slowed to move over the northwest Bahamas, bringing a total rainfall of 22.84 inches in Hope Town during the storm.
Other potential effects of climate change include greater storm surges, rapid intensification and wider range of tropical systems.
John Keefe contributed reports.
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