Tropical Storm Dolly formed in the tropical Atlantic on Thursday morning. After reviewing satellite imagery of Invest 96L, the National Hurricane Center determined that the system had developed a well-defined center of circulation on Thursday morning and had acquired tropical characteristics, with maximum sustained winds of at least 40 mph (65 km/h). Dolly is expected to continue moving quickly toward the west through the rest of this week.
The naming of Tropical Storm Dolly so recently after the death of famed country singer Dolly Parton is purely coincidental; the name Dolly has been on the six-year rotating list of Atlantic storms since 1996, and this is the 10th appearance of a storm named Dolly in the Atlantic dating back to 1953.
The Bermuda High is strong enough, and its southern periphery extends far enough south, to keep Dolly moving on a mainly west-northwest track during the next three days. The forecast cone extends out 72 hours instead of the usual 120 hours, suggesting that Tropical Storm Dolly is likely to be an open tropical wave just before reaching Puerto Rico.
As far as intensity goes, Dolly has only a small window of opportunity to strengthen. Any strengthening is expected to occur on Thursday. Beginning Friday, increasing southwesterly wind shear and dry air will keep Dolly confined to tropical storm strength. The system is forecast to weaken into an open trough, or back into a tropical wave, just before reaching the northeastern Caribbean over the weekend.
This would be the best-case scenario for the northeastern Caribbean, including Puerto Rico, where extreme drought conditions continue due to the onset of a very strong El Niño and persistent strong wind shear, which has significantly limited rainfall throughout the summer months.
At this point, there are no coastal watches or warnings in effect. The system is located more than 1,500 miles east of the Leeward Islands. However, Dolly should be monitored closely, as there is a low chance that watches or warnings could be issued as early as tomorrow for portions of the Lesser Antilles, at least for a brief period. It will all depend on how much the system weakens once it encounters dry air and increasing southwesterly wind shear on Friday. Remember that tropical alerts, such as watches and warnings, are based on wind speeds of the system; if the system downgrades, then local alerts by the National Weather Service offices of the islands will be issued, and likely will be more about rainfall than sustained winds.
The Leeward Islands can expect periods of heavy rainfall between Saturday and Sunday. The Virgin Islands, Puerto Rico, and Hispaniola should receive periods of heavy rainfall between Sunday and Monday. Because the ground is extremely dry and compacted, heavy rainfall — especially from training thunderstorms (several storms that pass over the same small area) — could produce flash flooding, particularly in mountainous areas.
Wind shear remains very strong across the central Caribbean and in areas just north of the region. This will likely prevent a weakened Dolly, or its remnant tropical wave, from regenerating as it moves closer to the United States. In fact, long-range models suggest that the wave will likely recurve to the north just east of the Bahamas. However, we will continue to monitor the situation, as several factors could change over the long term as we move into the middle of next week.
Tropical Atlantic climatology
The Atlantic hurricane season continues to be unusually quiet. The average formation date for the fourth named tropical system is August 15, making Dolly about 12 days behind schedule. In fact, by August 29, the Atlantic basin has typically produced its sixth named storm, which would be the “F” storm. So far this season, there have been no hurricanes in the Atlantic basin. The average date for the first hurricane is August 11, while the first major hurricane typically forms by September 1. At this point, it is safe to say that we will finish the month of August without a hurricane in the Atlantic basin.
Dolly expected to keep drought from worsening in the eastern Caribbean
With plenty of dry, sinking air in place over the Caribbean basin — due in part to the strengthening El Niño event across the tropical Pacific — drought conditions continued to expand and intensify across nearly all of the Caribbean this month. Drought conditions are particularly dire in Puerto Rico, where the capital of San Juan just suffered through its driest and second-hottest July on record. Rotating 48-hour water shut-offs now affect 180,000 customers on the island, as detailed in our August 13 post, What you need to know about the water crisis in Puerto Rico.
While isolated rainfall that fell during the past week briefly stabilized topsoil moisture in Puerto Rico and the U.S. Virgin Islands, rainfall was insufficient to overcome mounting deficits, and impacts to stream flows, agriculture, reservoirs, and aquifers continued to build. Similar conditions persisted across the U.S. Virgin Islands, where Extreme Drought (level 3 out of 4) remains entrenched. According to today’s Drought Monitor weekly summary for Puerto Rico, “conditions are poised to deteriorate even further in the coming weeks.”
However, Dolly’s remnants should bring one to four inches of rain over portions of the northeastern Caribbean early next week, particularly in the Leeward Islands, Virgin Islands, Puerto Rico, and Hispaniola. Much more rain than that will be required to actually improve drought conditions, though.
The ongoing intensification of El Niño will likely intensify drought across the Caribbean from this autumn into early 2027, as warned by the University of the West Indies Climate Studies Group Mona (UWI CSGM) and the Caribbean Institute of Meteorology and Hydrology (CIMH) in a joint news release on Wednesday. The release also cautioned that record heat may occur from next March through May, which are normally the hottest months of the year across the Caribbean. According to UWI CSGM co-director Michael Taylor, “We are seeing an emerging climate disaster whose impacts combine heat, drought, and marine extremes. Unlike a hurricane, the impacts will continue to build over months. However, that should not lessen the urgency or scale of our preparations. We must respond to the unfolding slow-moving crisis with the seriousness we bring to other major climate threats, since what we do now determines the options available to us later.”
This <a target=”_blank” href=”https://yaleclimateconnections.org/2026/08/tropical-storm-dolly-forms-in-the-atlantic/”>article</a> first appeared on <a target=”_blank” href=”https://yaleclimateconnections.org”>Yale Climate Connections</a> and is republished here under a <a target=”_blank” href=”https://creativecommons.org/licenses/by-nc-nd/4.0/”>Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License</a>.<img src=”https://i0.wp.com/yaleclimateconnections.org/wp-content/uploads/2020/10/ycc-favicon.png?resize=100%2C100&ssl=1″ style=”width:1em;height:1em;margin-left:10px;”>
<img id=”republication-tracker-tool-source” src=”https://yaleclimateconnections.org/?republication-pixel=true&post=141800&ga4=1401ERFF5Q” style=”width:1px;height:1px;”><script> PARSELY = { autotrack: false, onload: function() { PARSELY.beacon.trackPageView({ url: “https://yaleclimateconnections.org/2026/08/tropical-storm-dolly-forms-in-the-atlantic/”, urlref: window.location.href }); } } </script> <script id=”parsely-cfg” src=”//cdn.parsely.com/keys/yaleclimateconnections.org/p.js”></script>
