An intense tropical wave moved westward across Africa near the end of August, splashing down off the coast of Guinea on the 30th of that month. Unlike some of its predecessors, this system organized almost immediately and was desginated Tropical Depression Twelve southeast of Cabo Verde during the evening of August 31. The storm was large, but strengthened remarkably quickly. Curved convective bands soon surrounded the center and what appeared to be a dry slot in fact was incorporated into the circulation as a proto-eye. The depression became Tropical Storm Larry and didn't stop there. Rapid intensification brought it to the verge of hurricane strength less than a day later. Early on September 2, it was upgraded to a hurricane.
After that point, it took some time for Larry's internal structure to catch up with its impressive outer bands. Over the next day, an eyewall tried to form multiple times, though none of the attempts were quite closed all the way around. Furthermore, the storm had multiple concentric eyewalls at times, complicating the strengthening process. Gradual strengthening continued nevertheless and Larry became a category 2 on September 3. A final burst brought the storm to major hurricane status overnight. From there, it remained a category 3 for several days. uring this stretch, Larry also reached its peak intensity of 125 mph winds and a minimum central pressure of 955 mb. Structural changes continued, however: around September 6, Larry became an annular hurricane. This type of hurricane has a large symmetric eye and little in the way of banding features. They are also more resilient to changes in the surrounding environment.
Indeed, the enviroment around Larry did change some. It slowed down and turned northwest during the same period, and the slower motion over led to more cold water upwelling beneath the storm as it gained latitude. Waters in the area of the subtropical Atlantic it traversed were just as warm or warmer as those it had encountered before, but the high ocean temperatures did not extend as deep, leaving Larry susceptible to churning cold water up under itself. This didn't slow it down too much though, perhaps again due to the annular structure. The storm weakened back to a category 2 only on September 8th as some dry air disrupted the center, but it was larger than ever and was producing rough surf all along the Atlantic coast of north America.
The storm turned the corner and made its closest approach to Bermuda on September 9 as a strong category 1, around 170 miles east-northeast of the island. Despite the center being far away, Bermuda still experienced some gale conditions. From there, the storm turned north-northeast and accelerated as hurricanes usually do in the mid-latitudes. On the 10th, it crossed north of the Gulf stream and encountered much colder ocean temperatures. Despite that, it only weakened a little and maintained an impressive inner core as it slammed into Newfoundland that night. By then, its forward speed was over 45 mph, so hurricane conditions arrived and departed in only a few hours. Remarkably, Larry was still tropical as it entered the Labrador sea, and remained a hurricane north of 50° N. It finally became extratropical on the 11th at a latitude of 54° N.
Soon after, it merged with another extratropical low. Larry's journey northward, along with its interaction with a mid-latitude trough, had the effect of transporting a huge amount of warm air and moisture poleward. As a result, the last impacts of ex-Larry were pretty unusual: on September 12, the combined low moved off the coast of Greenland, causing a huge snowstorm that dumped several feet of snow in areas of southeastern Greenland.
The above image shows major hurricane Larry over the open Atlantic. The lack of outer banding features and large eye are typical features of an annular hurricane.
Larry was the first tropical cyclone to strike Newfoundland as a hurricane since Igor in 2010.
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