The 1931 Atlantic hurricane season was an active hurricane season, with a total of 13 storms recorded, which was the most since 1916. However, only three of them intensified into hurricanes and just one reached major hurricane intensity, which is Category 3 or higher on the modern-day Saffir–Simpson scale. Nine of the tropical cyclones were identified in real-time, while evidence of the existence of four other tropical cyclones was uncovered by the Atlantic hurricane reanalysis project in 2012 and added to the Atlantic hurricane database. Additionally, two of the tropical storms were upgraded to hurricane status as part of the reanalysis.
Overall, the first four tropical cyclones left mostly minor impact on land. In early September, the fifth system caused severe flooding in Puerto Rico, leaving considerable damage to sugarcane crops and causing at least 30 deaths. Just days later, the British Honduras hurricane formed in the Caribbean Sea. The most intense tropical cyclone of the season, it peaked as a Category 4 hurricane with maximum sustained winds of 130 mph (215 km/h). Striking British Honduras, now Belize, at peak intensity, the hurricane caused about 2,500 deaths and about $7.5 million (1931 USD) in damage there. It remains the deadliest hurricane in the history of Belize. The next hurricane caused significant damage in Puerto Rico and resulted in at least two fatalities. The remaining six tropical cyclones left little to no impacts on land.
Season summary
Tropical cyclogenesis began in late June, with a system developing over the western Caribbean Sea on June 24. The storm struck Mexico's Yucatán Peninsula and Texas before dissipating on June 28. In July, a cyclone also developed over the western Caribbean and struck the Yucatan Peninsula and Louisiana. August was slightly more active, featuring two tropical systems. Four cyclones originated in the month of September, including all of the season's three hurricanes. The sixth system, also known as the British Honduras hurricane, developed over the southeastern Caribbean on September 6. It became the most intense cyclone of the season, peaking as a Category 4 hurricane on the modern day Saffir–Simpson scale with maximum sustained winds of 130 mph (215 km/h). The hurricane made landfall in Belize at peak intensity on September 10. In October, two additional cyclones formed, though both remained well under hurricane intensity. The season's final three tropical cyclones developed in the month of November, with the last dissipating near the Bahamas on November 25.
A total of thirteen tropical cyclones developed, the most since 1916, though many remained weak, with only three intensifying into a hurricane. Only one system, the British Honduras hurricane, reached major hurricane status, which is Category 3 or higher on the Saffir–Simpson scale. Most of the storms also impacted land, but few left deaths or inflicted serious damage. Six of the systems made landfall or moved across the Yucatán Peninsula. Overall, the tropical cyclones of the season collectively resulted in $7.6 million in damage and approximately 2,533 deaths, with the vast majority of the destruction being caused by the British Honduras hurricane.
The season's total activity was reflected with an accumulated cyclone energy (ACE) rating of 48, far below the 1931–1943 average of 91.2, even though the season featured the highest number of tropical storms since 1916. In contrast, the previous season had an ACE value of 50, despite having 10 fewer tropical storms than the 1931 season. ACE is a metric used to express the energy used by a tropical cyclone during its lifetime. Therefore, a storm with a longer duration will have high values of ACE. It is only calculated at six-hour increments in which specific tropical and subtropical systems are either at or above sustained wind speeds of 39 mph (63 km/h), which is the threshold for tropical storm intensity. Thus, tropical depressions are not included here.
Systems
Tropical Storm One
Around 12:00 UTC on June 24, the season's first tropical cyclone developed just offshore the Yucatán Peninsula. It moved slowly north and intensified into a tropical storm six hours later in accordance with data from a nearby ship. After attaining peak winds of 50 mph (85 km/h) early on June 25, the storm struck the Yucatán Peninsula and subsequently emerged into the Gulf of Mexico. It did not intensify while over water, instead making a second landfall on the southern Texas coast at 22:00 UTC on June 27, with winds of 45 mph (75 km/h). The system weakened to a tropical depression eight hours later, dissipating over southern Texas after 18:00 UTC on June 28.