As if on cue, a tropical depression formed in the Gulf of Mexico on the first day of the 2023 Atlantic hurricane season.
A tropical depression is a tropical cyclone that has maximum sustained winds of 38 mph or less, according to the National Weather Service.
There are no coastal watches or warnings associated with the system, which is known as Tropical Depression Two. The depression is forecast to remain offshore, move south, have no impact on Florida and be short-lived, the National Hurricane Center said.
The depression could become Tropical Storm Arlene
In a Thursday afternoon update, the hurricane center said, “some modest intensification is forecast, and the depression could become a tropical storm tonight or tomorrow. However, the system should begin to weaken by Friday night and degenerate into a remnant low by Saturday.”
If it becomes a named storm, which would happen if its sustained winds reach 39 mph, it would become Tropical Storm Arlene.
As of 5:00 p.m. EDT, the depression had sustained winds of 35 mph and was located 305 miles west-northwest of Fort Myers, Florida, the National Hurricane Center said.
An Air Force Reserve Hurricane Hunter aircraft investigated the system Thursday, the hurricane center said.
Why is the depression moving south?
For Floridians, it’s very unusual to see a forecast with a storm tracking southward in the Gulf of Mexico, but weak, disorganized systems can keep forecasters guessing.
“Marginal systems outside the peak of the season in marginal environments can move in mysterious ways,” said James Franklin, a retired chief of the hurricane specialist unit at the National Hurricane Center.
Forecasts, definitions, preparation:Everything to know about hurricane season 2023.
Hurricane season is underway:Here’s the list of names for the 2023 Atlantic hurricane season.
Heavy rainfall, flooding possible across Florida – but not from the depression
Locally heavy rainfall is possible across much of Florida through the weekend, the hurricane center said.
However, weather advisories for heavy rain along Florida’s east coast, including a flood watch for some South Florida counties, aren’t related to the system in the Gulf, forecasters said. The rain is coming from “a plume of deep, rich moisture” over the region, said Zachery Law, a meteorologist with the National Weather Service in Melbourne.
Air flow over the region is also moving very slowly, if at all, so larger amounts of rain can accumulate, Law said.
Through Saturday, a general 1-2 inches of rain is likely to fall on the northern part of the Florida Peninsula, with 2-4 inches and locally higher amounts over the southern half, according to AccuWeather.
Flash flooding is possible in some areas where areas where thunderstorms stall or move very slowly for an hour or so, Weather.com said.
A flood watch is in effect for portions of Southeast and South Florida until Friday evening, the National Weather Service said. This includes the Miami and Fort Lauderdale metro areas.
Why would Arlene be the second storm of the season?
While the first named storm of the 2023 season will be Arlene, it will actually be the second storm of the season. A system in January was classified in May as a subtropical storm.
Since the classification came during a post analysis, it did not get a name and will be documented as “Unnamed.”
Forecast increases on first day of hurricane season
Top forecasters from Colorado State University slightly increased their forecast Thursday for the 2023 Atlantic hurricane season. They now predict 15 named storms, of which seven will be hurricanes. That’s up from their previous forecast of 13 and six.
The reason for the higher prediction is the near-record high water temperatures in the tropics, which support tropical storm and hurricane development. Those conditions will be doing battle with El Niño, a climate pattern in the Pacific. El Niño increases vertical wind shear in the Caribbean Sea and tropical Atlantic, which tears apart storms.
The six-month 2023 Atlantic hurricane season officially began Thursday and lasts until Nov. 30.
When is hurricane season?:Here’s when hurricane season starts and what to expect in 2023
Contributing: Cheryl McCloud, USA TODAY Network