Tropical Storm Humberto is here and another storm is likely. These areas should pay attention
By CNN Meteorologist Chris Dolce
Tropical Storm Humberto has sprung to life in the Atlantic, and there could be a double-dose of tropical trouble in the coming days: Another storm is likely to form near the Bahamas and put the East Coast on alert heading into the weekend.
Newly-formed Tropical Storm Humberto, the eighth named storm of the season, is located about 550 miles northeast of the Leeward Islands in the western Atlantic and is moving to the west-northwest with sustained winds of 40 mph. It’s forecast to become a hurricane by this weekend, but it’s too early to say whether it might bring significant impacts to Bermuda or elsewhere.
The other potential system of note is Invest 94L, which is currently a disorganized area of thunderstorms over the northeastern Caribbean that is likely to develop into a tropical depression or storm by this weekend as it approaches the Bahamas. The next name on the Atlantic season’s 2025 list is Imelda.
Unlike Gabrielle, this forecast is worth monitoring for those along the East Coast of the US given one of these potential systems could get close to the coast by early next week. But this is a very complicated, low-confidence forecast, so it’s too soon to say for sure there will be any impact.
US tropical trouble ahead? Maybe.
September’s first three weeks stayed mostly quiet, but the Atlantic has certainly sprung back to life, so it could be an active period ahead.
Invest 94L has a high chance to develop into a tropical depression or tropical storm once it nears the Bahamas late this week or this weekend, according to the National Hurricane Center.
“Invest” is simply a label the National Hurricane Center gives to a patch of stormy weather it wants to investigate for possible tropical development. Once tagged as an invest, additional data is gathered on the thunderstorm cluster, including its own computer model runs, to help forecasters more accurately predict its potential track and strength.
Uncertainty around how organized Invest 94L will become is still high, but increasingly hospitable atmospheric conditions and plenty of warm water fuel give it potential to develop.
A bona fide storm is no guarantee: it could never develop or develop but stay offshore between Bermuda and the US East Coast, similar to August’s Hurricane Erin, or approach the southeastern US coast early next week.
The paths of Tropical Storm Humberto and 94L are especially tricky to forecast because several conditions could affect their movement. The jet stream dipping over the Eastern US and high pressure east of Bermuda will both draw these systems generally northward. On top of that, if the two drift close enough together, they might start to interact — sometimes even pulling or swirling around each other — which makes their future tracks and strength even harder to pin down.
In the meantime, Invest 94L could produce flooding rain in Puerto Rico and the Virgin Islands Wednesday and that threat might linger into Thursday. Some areas could get up to 6 inches of rain, bringing the risk of flash flooding and landslides in areas with steep terrain.
Those in the Bahamas and along US East Coast should stay aware and updated over the coming days as confidence increases in the forecast.
Late-season formation hot spots shift closer to land
With October’s arrival, the breeding ground for storms shrinks westward away from Africa. The Gulf, Caribbean and western Atlantic are typical late-season formation zones, and since these regions are closer to land, any storms that form have a greater chance to cause dangerous impacts.
Storm activity decreases in the central and eastern Atlantic heading into October because the clusters of showers and storms emerging from Africa that act as seeds for hurricane formation become less numerous and weaker. Upper-level winds that rip apart storms also become more hostile in those regions.
The 2025 Atlantic season has been chugging along at a slower-than-average pace. Only seven named storms have formed through September 22, lagging behind the 1991-2020 average of 10 storms by that date, according to National Oceanic and Atmospheric Administration data.
Two of those storms have become hurricanes: Erin in mid-August and Gabrielle this week. That’s behind the average of four to five hurricanes that typically form by late September. There have been fewer, but more ferocious hurricanes. Fueled by much warmer-than-average water, Erin rapidly intensified into a Category 5, and Gabrielle similarly exploded into Category 4 strength Monday.
Four named storms typically form in October and November, including two hurricanes. But some seasons have produced plenty more: 2024, 2020 and 2001 had seven more storms after September, while the hyperactive 2005 season produced 11.
And late season storms still pack a punch. Hurricane Milton’s strike on the Florida Peninsula in early October last year was among the seven post-September storm formations last year.
It’s still too early to tell where 2025 will fall on the late season spectrum, but with plenty of warm water fuel close to land, it will be important to keep a close watch on any potential tropical threats.
The-CNN-Wire
™ & © 2025 Cable News Network, Inc., a Warner Bros. Discovery Company. All rights reserved.
