Hurricane San Ciriaco was an intense, long-lived Cape Verde-type hurricane that appeared east of the island of Martinique on 7 August (the system was first detected on 3 August as a tropical storm by a ship west-southwest of Cape Verde, however it was not identified on US Weather Bureau reports until 7 August). Moving at a speed of 27 km/h (17 mph), the storm crossed directly over the island of Guadeloupe on the afternoon of 7 August and passed 80 to 120 km (50 to 75 mi) to the south of St. Kitts. Here wind speeds of (192 km/h) 120 mph were recorded, making the storm at least a Category 3 hurricane on the Saffir-Simpson Hurricane Scale.
The hurricane strengthened as it passed through the islands, reaching a peak intensity with 240 km/h (150 mph) winds and a central pressure of 930 mb near the island of Montserrat. Continuing on its west-northwest track, the hurricane made landfall on southeastern Puerto Rico early on 8 August with 224 km/h (140 mph) winds. After moving off of Puerto Rico, the hurricane then skimmed the northeast coast of the Dominican Republic on 9 August as a Category 3 hurricane. The hurricane continued to move at a slow forward speed of less than 16 km/h (10 mph), passing through the Bahamas and taking a turn for the north. On 13 August, the hurricane’s center was proximal to Jupiter, Florida. Traveled almost parallel to the U.S. coast over the next few days, before turning west-northwest to come ashore on North Carolina’s lower Outer Banks near Diamond City on 17 August as a Category 3 hurricane with winds gusting to (224 km/h) 140 mph. The storm drifted over this area for two days before turning eastward and exiting the U.S. coast as a weakened Category 1 hurricane on 19 August. After leaving the United States, the hurricane moved eastward over the open Atlantic until it became extratropical on 22 August. The remnants of the storm managed to reorganize over open water and redevelop into a tropical storm on 26 August after turning to the north. As the storm was drifting, it again turned eastward and again strengthened into a hurricane while moving through the Azores on 3 September. The born-again hurricane was short lived, as it dissipated the next day moving northeastward.
The hurricane’s impact in Puerto Rico would prove to be one of the largest losses of life in relation to a hurricane in the history of the Atlantic basin. Overall, the island would be swamped by 28 days of rain. The official death toll from the storm in Puerto Rico was 3,433, with millions of dollars in crop damage. The U.S. mid-Atlantic coast, especially the Outer Banks of North Carolina, was also significantly impacted by this hurricane. Almost all of the houses in Diamond City and Shackleford, NC, were lost to storm surge, which was as high as 3 m (10 ft) in places. The hurricane also destroyed all fishing equipment in these towns, and as a result, the residents abandoned these establishments and searched to start over elsewhere.