The 1981 Atlantic hurricane season featured direct or indirect impacts from nearly all of its 12 tropical or subtropical storms. Overall, the season was fairly active, with 22 tropical depressions, 12 of which became named storms. 7 of those reached hurricane status and a further 3 intensified into major hurricanes. The season officially began on June 1, 1981, and lasted until November 30, 1981. These dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin. However, tropical cyclogenesis can occur before these dates, as demonstrated with the development of two tropical depressions in April and Tropical Storm Arlene in May. At least one tropical cyclone formed in each month between April and November, with the final system, Subtropical Storm Three, becoming extratropical on November 17, 1981.
Although many tropical cyclones impacted land, few caused significant damage. Tropical Depression Eight was the most devastating storm of the season, causing five fatalities and $56.2 million in damage due to flooding over southeast Texas in August. During the same month, Hurricane Dennis produced heavy rainfall across Florida's Miami metropolitan area and in parts of southeastern North Carolina, killing three people and leaving about $28.5 million in damage. Tropical Depression Two, Tropical Storm Bret, and Hurricane Katrina also resulted in fatalities. Collectively, the Atlantic tropical cyclones of this season were responsible for about $88.7 million in damage and 14 deaths.
Seasonal summary
The 1981 Atlantic hurricane season officially began on June 1 and ended on November 30. The season was high in activity, with 22 cyclones, 12 of which intensified into tropical or subtropical storms. Of those, seven intensified into a hurricane, while three strengthened into a major hurricane. This activity exceeded the National Oceanic and Atmospheric Administration (NOAA)'s 1950-2005 average of 11 named storms, 6 hurricanes, and 2 major hurricanes. Although most of the systems made landfall or otherwise impacted land, few caused extensive damage or fatalities. Collectively, the tropical cyclones of the 1981 Atlantic hurricane season caused about $88.7 million in damage and 14 deaths.
Tropical cyclogenesis began early, with two tropical depression forming in April, the first of which developing on April 6. Both tropical depressions were operationally unnumbered. Tropical Storm Arlene formed on May 6. The storm made landfall in Cuba two days later, before being absorbed later by a low. Tropical Depression Two moved out of the Gulf of Mexico into eastern Texas on June 5, producing localized rainfall amounts of and numerous tornadoes over Louisiana before recurving across the Southeast United States. Another previously unnumbered tropical depression formed over the Bay of Campeche later that month on June 17. It made landfall in Mexico south of Tampico before dissipating about two days later. Tropical Storm Bret formed as a subtropical low in the open Atlantic Ocean north of Bermuda on June 29, and made landfall in the Delmarva Peninsula.
The last of four previously unnumbered tropical depressions developed near Andros on July 2. It made landfall in southeast Florida and later in South Carolina before dissipating on July 4. Tropical Depression Four formed in the Gulf of Mexico on July 25, moving into Mexico the next day, and causing heavy rains in west Texas, Oklahoma, and Arkansas when its remnants moved into the United States. Tropical Storm Cindy formed on August 2 in the open Atlantic and became an extratropical cyclone on August 5. Hurricane Dennis formed on August 7 near South America. Dennis degenerated into a depression while making landfall in the Leeward Islands, but regained storm strength while over Cuba. Dennis moved near the southeast United States coastline from Florida to Virginia, briefly becoming a hurricane. Dennis weakened into a tropical storm and was declared an extratropical cyclone on August 22.
Tropical Depression Seven formed in mid-August and tracked through the Windward Islands before dissipating near Trinidad and Tobago. Tropical Depression Eight led to a significant flooding event between San Antonio and Houston on August 30 and August 31 while recurving through Texas into Louisiana. Hurricane Emily formed on September 1 southeast of Bermuda. Emily made a cyclonic loop as a tropical storm. Emily strengthened into a hurricane out in the North Atlantic Ocean and by September 12, was no longer identifiable. Hurricane Floyd was a Category 3 hurricane that grazed Bermuda, but no damage was reported. Hurricane Gert formed September 8, strengthened into a Category 2 hurricane, and followed the same track as Floyd, dissipating near the Azores. Hurricane Harvey became the strongest storm of the season, reaching Category 4 strength. Harvey never affected land, but ships reported tropical storm-force winds. Tropical Depression Thirteen brought gusts of tropical storm force to Bermuda in mid-to-late September. Hurricane Irene also stayed out at sea, reaching Category 3 strength before becoming extratropical in early October. The extratropical remnants of Irene made landfall in France.
Tropical Depression Fifteen was small and well-organized as it crossed the tropical Atlantic before weakening as it moved through the northeast Caribbean and southwest North Atlantic during late September and early October. Tropical Storm Jose was a short-lived storm forming out in the open Atlantic in late October. Jose never affected land and dissipated on November 1 near the Azores. Hurricane Katrina formed in the Caribbean Sea, and made landfall in Cuba after reaching hurricane strength. The final storm of the season, Subtropical Storm Three, formed in the Atlantic Ocean on November 12 and moved north, making landfall in Nova Scotia and becoming extratropical soon after.
The season's activity was reflected with an accumulated cyclone energy (ACE) rating of 100, which is classified as "near normal" by NOAA and is slightly higher than the 1951-2000 average of 93.2. ACE is a metric used to express the energy used by a tropical cyclone during its lifetime. Therefore, storms that last a long time, as well as particularly strong hurricanes, have high ACEs. It is only calculated for full advisories on tropical systems at or exceeding , which is the threshold for tropical storm intensity.
Systems Tropical Storm Arlene
An area of thunderstorms in the eastern Pacific Ocean crossed Central America into the western Caribbean, developing a low-level circulation on May 5 offshore Honduras. Convection organized enough that a tropical depression formed on May 6 near the Cayman Islands. It was a rare example of an Atlantic depression forming from a disturbance that originated in the eastern Pacific. Spiral rainbands developed around the center, and the depression intensified into Tropical Storm Arlene on May 7 while moving generally northeastward, steered by a ridge to its north. Arlene struck eastern Cuba early on May 8 with winds of 50 mph (85 km/h). Strong wind shear and Arlene's passage over land weakened the storm to a tropical depression and caused its circulation to become ill-defined. After an area of convection reformed, Arlene re-intensified after exiting Cuba, reaching winds of 60 mph (95 km/h) and a minimum pressure of over the southeastern Bahamas, based on observations from Hurricane Hunters. Arlene soon weakened to a tropical depression again and was absorbed by an advancing trough on May 9. Late the next day, the combined systems reorganized and resembled having some subtropical characteristics, but it weakened further by May 11.
As Arlene was approaching its first landfall, the National Hurricane Center noted the potential for heavy rainfall in Jamaica, Cuba, and the Bahamas; small boats in those regions were advised to remain at harbor. Meanwhile, the government of the Bahamas issued storm warnings for the central and southeastern portion of its country. There were no reports of damage or casualties from Cuba or the Bahamas, and therefore storm affects were judged to have been minimal. Early in the duration of Arlene, Cayman Brac reported winds; later, peak winds in the Bahamas reached around 35 mph (55 km/h). Arlene was the only May tropical storm on record to affect the Cuban province of Camagüey, although its passage was mostly noticed in its disruption of sugar cane production.
Tropical Depression Two
A tropical depression formed in the Bay of Campeche on June 3. Classified as Tropical Depression Two, the system moved north-northwest, lured by a closed upper-cyclone over the southern Great Plains. Shortly before 12:00 UTC on June 5, the depression made landfall near Matagorda, Texas, with winds of 35 mph (55 km/h) . Surface observations indicate that the depression's barometric pressure at landfall ranged from . Although the depression dissipated later on June 5, its remnants quickly recurved through the Mississippi Valley, and deepened as it moved off the coast of the Mid-Atlantic states into the Atlantic on June 7.
The depression, in conjunction with an upper-level low, dropped heavy rainfall in the Greater Houston area, with a peak total of at Lake Anahuac. In Texas City, of water inside 16 homes forced the evacuation of their occupants, with at least 23 homes suffering water damage. Water also entered city hall. Some roads had roughly of standing water, stranding some motorists for hours. In Galveston, a tornado damaged forty homes and apartments, with severe damage to three homes and two apartment units. One business suffered major roof damage, while several cars were damaged at an auto dealership. The depression also spawned eight tornadoes in Louisiana. The most destructive tornado touched down in Rapides Parish, where it substantially damaged or destroyed thirty-eight cars at a dealership in Lecompte, severely damaged five homes and caused minor damage to four others, downed large trees, and tossed an 18-wheeler truck approximately . Overall, the depression killed three people, two due to flooding and one from an associated tornado. At least $4 million in damage was caused by this depression.
Tropical Storm Bret
A low-pressure area initially associated with a frontal system developed into a subtropical storm on June 29 while roughly east of Cape Hatteras, North Carolina. The system headed westward and transitioned into Tropical Storm Bret around 06:00 UTC on June 30. Bret attained its peak intensity six hours later with maximum sustained winds of and a minimum atmospheric pressure of . However, Bret rapidly weakened as it approached the Mid-Atlantic and deteriorated to a minimal tropical storm by the time it made landfall on the Delmarva Peninsula early on July 1. The cyclone dissipated over northern Virginia several hours later.
Rainfall amounts were light, with a narrow area of over of precipitation reported near its track and within the central Appalachians, while a peak total of was observed at Big Meadows, Virginia. Locally heavy rains in western Pennsylvania caused some basement and street flooding. No significant damage was reported, but one fatality occurred at Nags Head, North Carolina, due to riptides.
Tropical Depression Four