Tropical Storm Arlene formed in the Gulf of Mexico on Friday, becoming the first named storm of the 2023 Atlantic hurricane season.
Arlene was about 165 miles west of Key West, Fla., on Saturday morning It was moving southeast toward Cuba at nine miles per hour. The National Hurricane Center said In a consultation. No coastal watch or warning is in effect, the hurricane center said.
The storm had sustained winds of about 40 mph, high winds and tropical-storm-force winds extending up to 70 mph from the center. But the storm is expected to weaken in the next 24 hours and dissipate on Sunday. However, parts of South Florida could get as much as 5 inches of rain through tonight.
Tropical disturbances with winds up to 39 mph get a name. Once winds reach 74 mph, a storm becomes a hurricane, and at 111 mph, it becomes a major hurricane.
Arlene is technically the second tropical cyclone to reach tropical storm strength this year. Hurricane Center Announced in May It determined that the storm that formed in the northeastern United States in mid-January was a subtropical storm, making it the Atlantic’s first hurricane of 2023. However, the storm was never named in advance, making Arlene the first named storm. Atlantic Basin this year.
The Atlantic hurricane season begins on June 1 and runs through November 30.
At the end of May, the National Oceanic and Atmospheric Administration predicted there would be 12 to 17 named storms this year, a “near normal” amount. There were 14 named storms last year, and after two very busy Atlantic hurricane seasons, forecasters ran out of names and had to resort to backup lists. (There were 30 named storms in 2020.)
However, NOAA did not express much certainty in its forecast this year, saying there was a 40 percent chance of a normal season, a 30 percent chance of a normal season, and a 30 percent chance of less. normal season.
There were signs of above-average ocean temperatures in the Atlantic this season, which could fuel storms, and the potential for an above-normal West African monsoon. The rainy season creates storm activity, leading to more powerful and long-lived Atlantic storms.
But forecasters also expect El Niño, an intermittent climate phenomenon that could have wide-ranging effects on weather around the world, to form this year. That could reduce the number of Atlantic hurricanes.
“It’s a very rare situation for both of these to happen at the same time,” Matthew Rosenkranz, lead hurricane forecaster at the Climate Prediction Center at NOAA, said in May.
In the Atlantic, El Niño increases the magnitude of wind speed, or changes in wind speed and direction from the ocean or land to the atmosphere. Cyclones require a calm environment to develop, and the instability caused by increased wind shear reduces those conditions. (El Nino has the opposite effect in the Pacific, reducing the amount of wind shear.) Even in average or below-average years, there is a chance that a powerful storm will make landfall.
As global warming worsens, that chance increases. There is a strong consensus among scientists that hurricanes are becoming more powerful due to climate change. Although there aren’t many named storms overall, the potential for major hurricanes is increasing.
Climate change also affects the amount of rain storms can produce. In a warming world, the air can hold more moisture, which means a named storm can receive more rain, as Hurricane Harvey did in Texas in 2017, with some areas receiving more than 40 inches of rain in 48 hours.
Researchers have found that over the past few decades, storms have slowed down and sat longer.
As the storm descends over water, the amount of moisture the storm can absorb increases. As the storm recedes over land, the amount of rainfall at a location increases. For example, in 2019, Hurricane Dorian slowed to a crawl over the northwestern Bahamas, resulting in nearly 23 inches of rain falling on Hope Town during the storm.
Other potential effects of climate change include greater storm surge, faster intensification and wider reach of tropical systems.
Remy Tumin Contributed report.