Storm Active: August 11-
On August 9, a strong tropical wave moved over the eastern Atlantic. The next day, it passed directly over Cabo Verde, bringing stormy conditions to the islands. It moved west-northwest away from the islands and became more organized over the next day. On August 11, the system was designated Tropical Storm Erin.
Erin's path was a little farther north than the deep tropics, putting it in an environment of drier air. This kept thunderstorm activity in check and prevented the storm from intensifying for the next few days. A strong ridge to the system's north steered Erin just south of west at a quick pace. By late on August 13, the storm's path brought it to warmer waters and a more favorable atmospheric environment. The storm began to strengthen and grow in size soon afterward, as well as slow down and turn toward the west-northwest. An inner core really began to take shape on the 15th, with large spiral bands extending well south and west of the center of circulation. That morning, Erin became the first hurricane of the 2025 Atlantic hurricane season.
Thunderstorms from Erin's outer edge reached the northeasternmost Caribbean islands that evening with the center still a few hundred miles distant. Overnight, an eye appeared on satellite imagery and explosive intensification began. Between 0000 UTC and 1200 UTC on August 16, Erin vaulted from a category 1 hurricane all the way to strong category 4 intensity. It also took a westward jog that morning, with the southern portion of the circulation brushing the Lesser Antilles. Fortunately, the center stayed a little more than 100 miles north of the islands, meaning that the worst conditions missed land.
The eye continued to become more symmetric as Erin deepened further. During the afternoon, the storm peaked as a category 5 hurricane, with sustained winds of 160 mph and a minimum central pressure of 915 mb. Erin became the earliest category 5 Atlantic hurricane to form outside the Caribbean and Gulf of Mexico on record. Also, Erin went from a tropical storm to a category 5 hurricane in just 25 hours, an unprecedented feat for an Atlantic hurricane. As is typical with hurricanes of this intensity, the storm experienced eyewall contraction a few hours after as an eyewall replacement began. The inner eye weakened and so did the storm's maximum winds, dropping it to category 3 intensity on August 17. However, Erin's eyewall replacement broadened its windfield signficantly over the following couple of days.
As the inner and outer eyewalls battled for dominance, the storm's forward movement also slowed. The expanding circulation brought rain bands across the Virgin Islands, Puerto Rico, and the Dominican Republic. By August 18, Erin was passing just northeast of the Turks and Caicos, close enough for the islands to experience tropical storm conditions. That same morning, a new, larger eye asserted itself, allowing the storm to deepen and restrengthen to category 4. Shortly after, however, wind shear increased significantly out of the north. This eroded the circulation to the point that the center was nearly exposed on the northern edge of the convection early on August 19. This caused Erin to weaken to a category 2. At the same time, a weakness in the ridge to the storm's north allowed it to turn northwest and then north.
The hurricane's structure changed yet again by August 20: slackening shear let Erin rebuild an inner core, and soon it had a symmetric eye again, surrounded by a compact inner core. Farther out was a massive second eyewall. The east side of the outer eyewall had some of the strongest winds in the system, despite its distance from the center! Because of this sprawling structure, Erin's peak winds did not increase that much and it remained just shy of major hurricane strength. However, it deepened significantly to a secondary minimum pressure of 941 mb on the 20th.
As of 5:00pm EDT on August 20, 2025, Hurricane Erin had maximum sustained winds of 110 mph, a minimum central pressure of 943 mb, and was moving north at 14 mph. For more up-to-date information and the latest watches and warnings, please consult the National Hurricane Center.
Wednesday, August 13, 2025
Monday, August 4, 2025
Tropical Storm Dexter (2025)
Storm Active: August 3-7
At the beginning of August, a frontal system moved off of the U.S. east coast. A low pressure center formed along the front shortly after, not far from the coast of North Carolina. It moved steadily east-northeast away from land and soon detached from the front. Late on August 3, it had fully shed frontal characteristics, and was already producing gale force winds. Therefore, it was named Tropical Storm Dexter.
From the time of its formation, wind shear out of the west continually increased over Dexter, causing the center to be exposed on the western edge of the convective canopy. The westerly flow northwest of a subtropical ridge over the central Atlantic kept the storm on a steady, but not especially rapid, east-northeast heading. The marginal conditions ensured that Dexter did not strengthen much within the next couple of days. On August 6, the cyclone began to show signs of extratropical transition as shear increased further and the center became elongated. The next day, Dexter became extratropical. The storm actually achieved its peak winds as an extratropical cyclone, with sustained winds approaching hurricane strength as it moved out to sea over the North Atlantic.
Dexter was a sheared storm throughout its short stint as a tropical cyclone.
After forming near land, Dexter moved steadily out to sea.
At the beginning of August, a frontal system moved off of the U.S. east coast. A low pressure center formed along the front shortly after, not far from the coast of North Carolina. It moved steadily east-northeast away from land and soon detached from the front. Late on August 3, it had fully shed frontal characteristics, and was already producing gale force winds. Therefore, it was named Tropical Storm Dexter.
From the time of its formation, wind shear out of the west continually increased over Dexter, causing the center to be exposed on the western edge of the convective canopy. The westerly flow northwest of a subtropical ridge over the central Atlantic kept the storm on a steady, but not especially rapid, east-northeast heading. The marginal conditions ensured that Dexter did not strengthen much within the next couple of days. On August 6, the cyclone began to show signs of extratropical transition as shear increased further and the center became elongated. The next day, Dexter became extratropical. The storm actually achieved its peak winds as an extratropical cyclone, with sustained winds approaching hurricane strength as it moved out to sea over the North Atlantic.
Dexter was a sheared storm throughout its short stint as a tropical cyclone.
After forming near land, Dexter moved steadily out to sea.