Bryan Norcross: Tropical Storm Dexter and more areas to watch in the Atlantic

Updated at 11 a.m. ET on Monday, Aug. 4, 2025

Tropical Storm Dexter is well off the coast of North Carolina and moving out to sea. The storm is going to have a short life. It’s already encountering hostile upper-level winds, so it will soon be absorbed into the North Atlantic flow.

Dexter was spawned by the stubborn frontal system stretching from the Atlantic waters off the East Coast, across North Florida and South Georgia, and along the Gulf Coast. The front is the dividing line between relatively cool air to the north and moist tropical air to the south.

TROPICAL STORM DEXTER FORMS OFF US EAST COAST IN ATLANTIC OCEAN

Offshore of the Southeast

Low-pressure systems form along fronts like this – they are called frontal waves. If one of these lows sits over the warm Atlantic water, and the upper-level winds are conducive to development, a tropical system can spin up. That's what happened with Dexter, and it could happen again off the South Carolina coast.

The National Hurricane Center is drawing a mini lemon indicating a chance that another frontal low will park over the warm water long enough to take on some tropical characteristics. The ocean water offshore of the Carolinas is unusually warm this year.

NHC forecasters have the system’s odds of development in the low range.

2 OTHER AREAS TO WATCH IN ATLANTIC FOR TROPICAL DEVELOPMENT JOIN TROPICAL STORM DEXTER

About Thursday, the same time the computer forecasts show the low developing off the Southeast coast, a weak disturbance full of moisture is forecast to arrive from the Atlantic injecting moisture into the frontal low, but also pushing a moisture surge across the Florida Peninsula.

The net of all this is the likelihood of heavy rain from the Carolinas to South Florida late in the week. A depression could form, but nothing strong is likely to come of it. The issue is the expected flood potential from heavy and/or persistent rain.

The system hasn't even started thinking about forming, so any prediction comes with large errors and the high likelihood that it's going to change. So just in case something worse-than-expected happens, stay informed in the affected areas.

HOW TO WATCH FOX WEATHER

In the tropical Atlantic

A moderately robust disturbance moving off the coast of Africa has a decent chance of becoming at least a tropical depression somewhere in the large orange area drawn by the National Hurricane Center. The orange color indicates that the chances of development are in the medium range.

The various computer forecast models – including the new AI models – offer a wide variety of outcomes for this system. Most of the predictions show the system turning north into the dry and dusty air and not affecting land, although the American GFS model has been insisting that the blocking high-pressure system will rebuild across the Atlantic and push the system farther west. 

Things are going to move slowly, so we’ll have lots of time with this system.

The caveats all apply here, of course. The system is just moving off the coast, so until about midweek, the computer systems won't have a good starting point from which to begin forecasting. 

More systems are behind this one over the African continent, and long-range computer forecasts show some development with them. Next week’s system is preliminarily forecast to take a more southern track where more moisture is available. We’ll see. 

The long-anticipated weather regime that is more conducive to tropical development seems to be getting underway a little ahead of schedule.

There is no indication of any strong storms threatening land, certainly for the next week. But across the South into the mid-Atlantic, plan to stay informed later this week when we should have a better handle on what might or might not develop in the lemon drop offshore of the Carolinas. 

Some local flooding is likely. Stay aware of alerts issued by the National Weather Service.