On September 7, a tropical wave emerged off the coast of Africa. It moved steadily west-northwestward over the next several days, but didn't organize too much due to marginal conditions: dry air was still unusally prevalent across the Atlantic basin. Nevertheless, the system ultimately prevailed over its surroundings and became Tropical Depression Seven on September 14. The new depression's center was on the western edge of the main convective mass, but that associated thunderstorm activity was quite vigorous. By later in the day, the system was generating gale force winds and strengthened into Tropical Storm Fiona.
The storm moved due west over the next couple of days and managed to intensify some, even though the center of circulation was consistently outrunning any associated thunderstorm activity. As Fiona's rainbands chased its naked low-cloud swirl westward, the storm began to affect the Lesser Antilles on September 16, bringing a slew of heavy rain to the islands. After entering the northeast Caribbean sea, the system slowed down and the large-scale circulation improved in symmetry. However, Fiona was still ingesting dry air on the 17th. As a result, it was difficult for the tropical storm to develop a central dense overcast, a prerequisite to further strengthening. The system also began to feel a weakness in the subtropical ridge and turned north of west by that evening.
Suddenly, on Sptember 18, Fiona got its act together and started to organize quickly, probably due to higher ocean heat content and moister air in the Caribbean. Late that morning, it strengthened into a hurricane. By that point, the center was approaching the southern coast of Puerto Rico. Rain had already begun on the island, but an exceptional rain event began that afternoon when Fiona's burgeoning eyewall pushed ashore. The center of circulation made landfall in extreme southwest Puerto Rico a few hours after that, but had soon moved northwestward over water again in the Mona Passage.
That night, the storm made a second landfall near the eastern tip of the Dominican Republic as a high-end category 1 hurricane, becoming the first hurricane to make direct landfall in that nation since Hurricane Jeanne in 2004. Fiona passed over only relatively low-lying land areas, so land interaction scarcely hampered the hurricane. Early on the 19th, it emerged off the northern coast and began to strengthen again. An eye became evident on satellite imagery that day and Fiona was upgraded to a category 2. By that time, the rain event had finally concluded in Puerto Rico and most of the Dominican Republic, where over 25 inches of rain were recorded in certain areas.
The far eastern Bahamas also had a close brush with the storm early on September 20 as it turned north-northwestward and passed just to the east of the islands. Though the Bahamas experienced the less intense western semicircle of the storm, hurricane conditions still affected those regions for a few hours. Around the same time, Fiona intensified into the first major hurricane of the 2022 season. The storm moved away from the Bahamas and strengthened further over the next day. Even more pronounced was its increase in size; much of Fiona's decreasing pressure contributed to an expansion of its wind radius through a series of frequent eyewall replacement cycles. Early on September 21, the system reached category 4 status.
The hurricane turned north-norhteast and accelerated that day as it began to feel the influence of a powerful trough over eastern North America. On the 22nd, gale conditions enveloped Bermuda as Fiona approached. That night, the storm reached its peak intensity as a tropical cyclone of 130 mph winds and a minimum central pressure of 932 mb. Fortunately, the hurricane passed well west of Bermuda, preventing it from feeling the worst impacts. The same could not be said for Atlantic Canada: by early on the 23rd, the system was turning back north toward Nova Scotia. The front approaching Fiona began to interact and merge with the hurricane, making the circulation more asymmetric and beginning extratropical transition. Maximum winds dropped but the storm's barometric pressure remained extremely low as it transitioned that day.
When night fell, Fiona was rocketing northward at over 40 mph. It officially became post-tropical late in the evening but this did not mitigate impacts much when it slammed into eastern Nova Scotia in the early morning hours of September 23. Tropical storm force winds affected an extremely large area from eastern Maine to Newfoundland. Hart Island, Nova Scotia recorded a central pressure of 931.6 mb in Fiona; in terms of pressure, the storm's peak intensity likely occurred just after post-tropical transition. Not only that, but this pressure reading was the lowest ever recorded in Canada from any storm in history, crushing the previous mark of 940.2 mb set in a winter storm on January 20, 1977 in Newfoundland. The damage from wind and storm surge was severe in much of Maritime Canada.
After landfall, ex-Fiona slowed down and weakened, eventually moving over Labrador on September 24. The post-tropical storm continued to bring strong winds to Canada as it slowly spun down over the next several days.
The above image shows Fiona undergoing an eyewall replacement cycle on September 21. At the time it was located over the open Atlantic between the Bahamas and Bermuda.
Extremely warm waters and a trough interaction allowed Fiona to remain an extremely intense cyclone upon landfall in Nova Scotia.
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