How Hurricane Oscar fooled forecasters, became smallest on record
Hurricane Oscar, now downgraded to a tropical storm over Cuba, was the smallest hurricane ever recorded in the Atlantic basin, meteorologists said Monday.
When the storm formed Saturday, hurricane hunters found Oscar’s hurricane wind field was only 5 to 6 miles across.
"This not only made Oscar the smallest hurricane of the 2024 hurricane season but the smallest hurricane ever known, with observational records of hurricane wind fields going back to the mid-1960s," said WPLG-TV meteorologist Michael Lowry, who said such small hurricanes are "extremely rare."
According to the record books, Oscar is the first hurricane to have hurricane-force winds less than 11.5 miles across, he said.
Size helped evade detection
According to the Weather Network, Oscar’s size allowed the storm to evade detection by satellites and initially "bamboozled weather models." Forecasters discovered its advanced strength only when a hurricane hunter aircraft penetrated the storm’s core.
"Even our most state-of-the art, highest fidelity global forecast models (like the oft-cited European model) can’t 'see' weather features that are smaller than 5 or 6 miles in size (it’s why we can’t forecast individual tornadoes, only the overall setup that can lead to big tornadoes), so it’s no wonder they missed Oscar," Lowry said Monday in his blog.
Before Oscar, the smallest Atlantic storm on record was Tropical Storm Marco in 2008, the Weather Network said.
How strong was Oscar?
Though Oscar officially peaked as a Category 1 hurricane this weekend, "very-high-resolution wind estimates derived from low-Earth orbiting Canadian satellites suggested it could’ve been as strong as a Category 2 or 3 hurricane before striking the tip of eastern Cuba Sunday evening," Lowry said.
Oscar not done yet
Through midweek, heavy rainfall from Oscar will lead to areas of significant, life-threatening flash flooding along with mudslides across portions of eastern Cuba, the National Hurricane Center said. "In addition, localized flash flooding will be possible across the southeastern Bahamas."
In the U.S., powerful waves from Oscar could hit East Coast beaches in the coming days, according to the National Weather Service in Melbourne, Florida.
Oscar formed just hours after Tropical Storm Nadine, which made landfall in Belize on Saturday before dissipating in southern Mexico on Sunday, Weather.com said.