Hurricane Season Heating Up

Dexter forms and moving away from the U.S. but more to follow as the Atlantic comes alive

We’ve been previewing a busy start to August in this newsletter for almost a month, describing the behind-the-scenes developments signaling an uptick in Atlantic activity, and, two weeks ago, advertising an August 3^rd wake-up call for the basin. Judging by today’s map, our outlook met the mark, with the Atlantic springing to life over the weekend.

Dexter up first but moving out to sea

The frontal low off the Carolinas that we discussed in Friday morning’s newsletter, first mentioned by the National Hurricane Center in its outlook on Saturday, took advantage of conducive conditions, including record warm waters between the southeast U.S. and Bermuda, to outperform model expectations and become Tropical Storm Dexter late Sunday.

Thankfully, this one has probably already peaked and will be rounding the western side of the Bermuda High out to sea. Dexter, while posing no threat to land, is the opening act for the show the Atlantic’s threatening to put on behind it.

Dexter’s DNA boomerangs back

As Dexter scurries out to the high Atlantic graveyard, the same nuisance front that helped spawn it may cleave off yet another system in its wake over the next few days. For now models are lukewarm on much development but unlike Dexter, building high pressure will shove it westward and toward Florida, Georgia, or the Carolinas by late week into the weekend.

Total rainfall forecast through Saturday morning (August 9, 2025) from the National Weather Service’s Weather Prediction Center. Though models now show the heaviest rainfall just off the Carolina coast, we’ll need to watch to make sure the threat doesn’t creep up farther inland. Credit: Pivotal Weather

For now, it’s more likely a potential rainmaker for the latter part of the week, but given the record-warm waters in the vicinity, we’ll want to keep tabs on it in case it overachieves.

Models preview main event next week

Exiting the coast of Africa over the past 24 hours is a robust tropical wave that models suggest has a good chance of becoming a named storm and possibly our first hurricane by this weekend or early next week over the central Atlantic.

This one is expected to lift far enough north to not pose a threat to the islands of the Caribbean. Beyond this weekend, forecast models diverge, with the Euro curling the system out to sea and the American GFS continuing a track west-northwestward, missing the first escape route.

Comparison of forecast low-pressure tracks from the European model ensemble system (top) and American GFS ensemble system (bottom) through next Monday, August 11, 2025. The European model has a weaker subtropical high pressure, which allows the developing system to escape out to sea. The American GFS maintains stronger high-pressure steering, which keeps the system moving farther westward through the Atlantic into early next week. Neither model suggests a threat to the islands surrounding the Caribbean. Credit: Weathernerds.org

Bottom line: we have plenty of time to monitor and at least for the next week, this won’t be a threat to any land areas.

More strong waves on deck

Forecast models don’t show the Atlantic letting up into the middle of the month. Another wave will be moving through the main tropical belt of the Atlantic next week that longer-range models also indicate has a conducive environment for organization.

Probability of a tropical depression or stronger passing to within about 175-200 miles of a given location from next Tuesday through Wednesday (August 12-13, 2025) according to the European model ensemble system. The model shows a decent signal for potential development for the middle part of next week across the tropical belt between Africa and the Caribbean. Credit: Weathermodels.com

It’s too soon to say much about the next system, but conditions overall look ripe for activity. We’ll need to pay attention to any system that gets closer to the mainland U.S. where waters are especially warm relative to the rest of the basin.

As always, check back periodically for updates in the coming days and weeks.