A tropical disturbance moving across the central Atlantic is becoming increasingly likely to develop into a tropical depression later this week, with forecasters raising its chance of formation to 70%.
The area of low pressure was located about 500 miles (805 km) southwest of the Cabo Verde Islands on Tuesday, August 11. Shower and thunderstorm activity around the system remained limited, but environmental conditions are forecast to become increasingly favorable for development during the next couple of days.
The U.S. National Hurricane Center (NHC) now gives the disturbance a 30% chance of tropical cyclone formation within 48 hours and a 70% chance within seven days.
Forecasters expect the system to continue moving generally west to west-northwest across the central tropical Atlantic, with a tropical depression likely to form during the latter half of the week.
Development chances are climbing
The change over the past 24 hours is significant.
On August 10, the disturbance had a 20% probability of developing within 48 hours and a 60% probability over seven days. By Tuesday morning, those probabilities had increased to 30% and 70%, respectively.
The system was previously expected to interact or merge with a tropical wave moving away from West Africa. As it progresses farther across the Atlantic, the surrounding environment is forecast to become more conducive to organization.
For now, however, its thunderstorms remain limited, meaning a fully organized tropical cyclone has not yet formed.
A tropical depression requires an organized circulation and sustained winds below tropical-storm strength. If the system continues strengthening and maximum sustained winds eventually reach 39 mph (63 km/h), it would be classified as a tropical storm.
Could Tropical Storm Cristobal form?
If that happens, the cyclone would receive the name Cristobal, becoming the third named storm of the 2026 Atlantic hurricane season.
Only Tropical Storms Arthur and Bertha have been named so far this season.
The season is running somewhat behind the climatological pace for named storms. The Atlantic’s third named storm typically forms by around August 3.
There is still substantial uncertainty over what happens after the disturbance develops.
Global forecast models generally keep the system away from the Gulf of Mexico during the next week or so. Two areas of high pressure could eventually help steer the developing cyclone northward over the open Atlantic.
However, confidence in a long-range track remains limited because the tropical cyclone itself has not yet formed.
For now, there is no immediate threat to Texas or the U.S. Gulf Coast.
Caribbean islands farther east are watching the system more closely. In Anguilla, authorities had not issued an official notice on the disturbance as of Tuesday, although residents were being advised to follow its progress because it remains too early to determine whether the island could eventually be affected.
Two other Atlantic disturbances are being monitored
The NHC is monitoring two additional areas across the Atlantic, although neither currently has development potential comparable with the system southwest of Cabo Verde.
A tropical wave roughly 600 miles (965 km) east of the Windward Islands is producing disorganized showers and thunderstorms while moving westward.
The wave is expected to encounter a large area of dry environmental air as it approaches the Lesser Antilles, making significant tropical development unlikely.
Its formation probability has fallen to near 0% through both 48 hours and seven days.
Even without becoming a tropical cyclone, however, the disturbance could produce locally heavy rainfall and gusty winds across portions of the Lesser Antilles during the next couple of days.
Farther north, forecasters are watching a trough of low pressure several hundred miles northeast of Bermuda.
The system is moving east at about 20 mph (32 km/h) and has a 10% probability of tropical cyclone formation.
Some short-lived development remains possible, but the disturbance is expected to encounter cooler ocean waters later this week. That should make conditions increasingly unfavorable and effectively close its window for tropical development by Thursday.
Central Atlantic becomes the main area to watch
Of the three Atlantic disturbances currently being monitored, the low southwest of Cabo Verde is clearly the most likely to develop.
Its seven-day formation probability has climbed from 60% to 70% in only a day, while the NHC has strengthened its wording from saying a tropical depression “could” form to saying one is now “likely” during the latter half of this week.
Exactly where the system ultimately travels will depend partly on how quickly a defined circulation develops and how the surrounding steering pattern evolves.
Until then, the disturbance remains an area of low pressure rather than Tropical Storm Cristobal, but the central tropical Atlantic has become the main region to watch as the 2026 hurricane season moves closer to its climatological peak.
