Late Tuesday night, a tropical wave over the northeastern Caribbean Sea developed into Tropical Storm Fred, the sixth named storm of the 2021 Atlantic hurricane season. Fred’s formation ends a lull of Atlantic tropical cyclone activity that lasted over a month. Fred’s formation date is still significantly earlier than the average sixth Atlantic named storm, but is over a month later than Tropical Storm Fay’s formation on July 9 last year.

As of 5:00 p.m. EDT Wednesday, Tropical Storm Fred was centered near 18.9°N 71.0°W, and was moving west-northwestward at about 15 mph. Maximum sustained winds were 35 knots (40 mph), with an estimated minimum pressure of 1007 mb. Fred was slightly stronger earlier this morning as it made landfall in the Dominican Republic, with maximum sustained winds of 40 knots (45 mph). Since that time, Fred’s circulation has likely started to become disrupted by interaction with the mountainous terrain of Hispaniola. It remains uncertain how much the mountainous terrain will disrupt the current circulation, and it remains a distinct possibility that Fred could lose its weak low-level circulation. Another possibility is the low-level circulation center jumps north and reforms just north of the island. At the moment, the current National Hurricane Center (NHC) forecast predicts Fred will weaken to a tropical depression and begin to restrengthen slightly on Friday. The interaction with land is likely to keep Fred’s low-level and mid-level vorticity centers misaligned, which will impede development. In addition, the 18z SHIPS guidance indicates that wind shear will remain moderate – around 20 knots (25 mph) – for the next few days. This should keep Fred weak and disorganized as it passes close to Cuba and south of the Bahamas. On Saturday, Fred should turn more to the northwest, and environmental conditions could become slightly more favorable for re-intensification if Fred is able to maintain a closed low-level circulation at that point. Regardless, it appears that Fred will not have much time over water in the Gulf of Mexico, if at all, suggesting it is unlikely that Fred ever becomes a strong tropical cyclone. Tropical Storm Warnings remain in effect for the eastern Dominican Republic, though they will likely expire later this evening. Tropical Storm Watches are currently in effect for northern Haiti, the Turks and Caicos Islands, and the coasts along the eastern half of Cuba. So far, no watches and warnings have been issued for the United States. Interests in the Florida Peninsula should continue to monitor the progress of Fred.

There is another tropical wave, Invest 95L, currently being monitored by the NHC for potential development. As of 18:00 UTC Wednesday, Invest 95L was centered near 12.1°N 35.0°W, and was moving westward at around 20 mph. Maximum sustained winds were 20 knots (25 mph), with an estimated minimum pressure of 1010 mb. The NHC gave 95L a 30 percent chance of development within 48 hours, and a 50 percent chance within five days in their most recent Tropical Weather Outlook. 95L is currently producing disorganized showers and thunderstorms, and lacks a tight, well-defined circulation center. Easterly shear of around 15-20 knots is currently affecting the disturbance, but this shear is expected to decrease to less than 10 knots on Friday, giving 95L a window to develop into a tropical cyclone as it approaches the Leeward Islands. The 12z GFS model did not suggest development, while the 12z ECMWF model run predicted 95L would develop into a tropical depression by Sunday as it approached the Leeward Islands. The 12z UKMET model run also suggested some modest development would occur just north of the Greater Antilles. Much like Fred, a big question about 95L is land interaction if development occurs. 95L taking a track over the Greater Antilles would likely impede development, but if 95L is able to develop into a tropical cyclone sooner and pass north of the islands, it would have potential to be something more significant. There are some other negative factors working against 95L’s development prospects. For the next four days or so, the 700-500 mb relative humidity values are expected to be a marginal 55-60 percent, according to the GFS-based SHIPS guidance. In addition, the SHIPS guidance suggests shear could increase to more than 20 knots (25 mph) after Day 5. 95L’s forecast is highly uncertain, and will become clearer over the coming days, since we do not even know yet if a cyclone will develop. If 95L becomes a tropical storm, it will be named Grace.