Near the end of August, a low pressure center formed along a decaying frontal boundary over the subtropical Atlantic ocean. Due to very warm ocean waters for that latitude, the disturbance was able to quickly consolidate into Tropical Depression Five on September 1 (the number "Four" had been given to a potential tropical cyclone in the Gulf of Mexico a few weeks prior, though that system never attained tropical cyclone status). Shortly afterward, the depression strengthened into Tropical Storm Danielle. The formation of Danielle ended an incredible drought of cyclone formation in the Atlantic that had reigned since July 3. 2022 was the first year since 1997 that no named storm developed in the Atlantic during the month of August.
Danielle formed around 38 ° N. Storms at that latitude tend to quickly exit northeast and become extratropical, but an unusual blocking high pressure was keeping the system almost in place. As a result, the storm scarcely moved at all over the next few days. In contrast, Danielle was changing quickly in strength. It had a compact circulation with a ring of deep convection about the center, all favorable factors for rapid intensification. By midday on September 2, the storm had already reached category 1 hurricane strength, becoming the first hurricane of the season.
The next day, some dry air from the north invaded Danielle's circulation. This disrupted the eyewall and temporarily weakened the cyclone back to a tropical storm. Eventually, the storm overcame this intrusion and restrengthened to a hurricane late on September 3. Even through the morning of September 4, the storm had hardly moved at all from where it formed. Danielle finally began to budge northward only that evening as it moved toward a weakness in the ridge to its north. Meanwhile, the storm was able to strengthen a little further to its peak intensity of 90 mph winds and a central pressure of 975 mb (a high-end category 1).
The hurricane encountered cooler water as it began to pick up speed and turn toward the northeast. As a result, some of the thunderstorm activity of the inner core collapsed on the 5th, beginning a trend of gradual weakening. Nevertheless, Danielle's satellite presentation remained impressive, with a large eye surrounded for the most part by deep convection. The next day, the storm continued northeast in the mid-latitude westerly flow and an approaching trough increased wind shear in the vicinity. It remained a hurricane through September 7.
By September 8, Danielle had little central convection left. It was downgraded to a tropical storm and became post-tropical right after. The remnants of Danielle executed a counterclockwise loop and then rocketed east. After a few more days, the weakening remnants dissipated near the coast of Portugal.
The above image shows Danielle as a hurricane over the open northern Atlantic on September 5.
Danielle was nearly stationary for its first few days as a tropical cyclone, but climatology ultimately took over and it exited northeast out to sea.
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