A tropical depression that is building up over the Memorial Day weekend in the Gulf of Mexico is becoming increasingly unavoidable.
On Thursday, predictions from the National Hurricane Center increased the likelihood of a storm developing from a system near the Yucatán Peninsula 70 percent in the next two days and 90 percent in five days. Computer models also agreed on a likely scenario: a depression or named storm that eventually lands on the coast of Florida Panhandle or Louisiana.
While some models suggest that the system could become a category 1 hurricane, hurricane researcher Brian McNoldy of the University of Miami said it's still too early to reliably listen to the intensity.
"You do not read too much into human subjective input," he said. "You can easily be wrong at this point because it is still a very disorganized vortex over the Yucatán."
A hurricane fighter aircraft is due to investigate the system on Friday.
South Florida's biggest threat remains heavy rain, which could begin on Friday. Floods are possible even after a month of heavy May rains.
"The terrain is now pretty saturated," said Andrew Hagen of the National Weather Service Miami. "I would not say they are extremely saturated, but they are pretty saturated, so areas that get heavy rains might see some flooding problems."
The slow moving system began attracting the attention of meteorologists last week when computer models indicated that the vortex of low pressure near Belize could get steam, AccuWeather senior forecasters said Dan Kottlowski. While the official hurricane season does not start until next Friday, the Gulf waters are already warm enough to heat up a tropical cyclone when atmospheric conditions are favorable.
A preseason storm is unusual, but not uncommon, and usually forms in May. At least eight have occurred in the Atlantic over the past decade, including the Arlene Tropical Storm in April 2017 over the Central Atlantic.
The proximity of the system to the coast and the wind shear have kept it in check until now and left it a crooked mess. However, the upper winds are expected to move east, forcing them over warm waters to the north.
"When the gravure moves away from the land, it only has the open part of the Gulf," Kottlowski said.
If the system goes awry, it could become a subtropical system with stronger winds beating around the edges of the storm than the center, where the winds are strongest in a tropical storm. Subtropical systems resemble tropical ones and produce the same dangers – wind and heavy rain – but are more elliptical and have no warm center. Emagazine.credit-suisse.com/app/art … = 157 & lang = DE "You'll still get the dangers of winds and heavy rain, but it 's just nice. Emagazine.credit-suisse.com/app/art … = 157 & lang = DE That' s why the strongest winds are not necessarily near the center of the system, "said Dennis Feltgen, spokesman for the hurricane center.
Heavy rain is a problem for South Florida because so much has already fallen this month. In some places, the totals are three times the monthly average, a dramatic jump from April, when precipitation was well below average, leaving the region unusually dry, and raging wildfires over the Big Cypress National Preserve.
In preparation for possible floods, the South Florida Water Management District will continue to keep channel levels low in Broward and Miami-Dade, spokesman Randy Smith said Thursday.
"We had a very large amount of rain As of May 13, we have operated essentially 24 hours a day pumping stations and gate operations," he said. "We will continue this 24/7 until we can do it."
The Gulf Coast should also look for strong countercurrents, meteorologists said.
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