The
2020 Atlantic hurricane season was the most active
Atlantic hurricane season on record in terms of number of
named storms. Additionally, it was as an above-average season for
tropical cyclones for the fifth consecutive year.[nb 2][2] The season officially began on June 1, 2020, and ended on November 30, 2020. These dates, adopted by convention, historically delimit the period each year when most Atlantic
tropical systems form.[3] However, storm formation is possible at any time of the year, as was the case this season, when its first two named storms,
Tropical Storm Arthur and
Tropical Storm Bertha, formed on May 16 and May 27, respectively. The final storm,
Hurricane Iota, dissipated on November 18.
Altogether, the season produced 31 tropical or
subtropical cyclones, all but one of which became a named storm. Of the 30 named storms, 14 became hurricanes, and seven further intensified into major hurricanes.[nb 3] It was the second and final season to use the
Greek letter storm naming system, the first being
2005.[5]Hurricane Laura produced catastrophic storm surge levels, heavy rainfall, and spawned over a dozen tornadoes after striking
Louisiana on August 27 with winds of 150 mph (240 km/h). The storm was responsible for 81 deaths and it caused over
US$19 billion in damage across the
Greater Antilles and the
Southern United States.[6] Causing significant late-season loss of life and widespread destruction were November hurricanes
Eta and Iota, which made landfall in
Central America as Category 4 storms just two weeks apart.[2] The storms left a toll of 184 deaths and 110 missing across the region, and thousands of families lost their homes and livelihoods.[7] In March 2021, the names Laura, Eta and Iota were
retired from reuse in the North Atlantic by the
World Meteorological Organization due to the extraordinary amount of damage and number of fatalities they caused.[8]
This timeline documents tropical cyclone formations, strengthening, weakening,
landfalls,
extratropical transitions, and dissipations during the season. It includes information that was not released throughout the season, meaning that data from post-storm reviews by the
National Hurricane Center, such as a storm that was not initially warned upon, has been included.
By convention, meteorologists use one
time zone when issuing forecasts and making observations:
Coordinated Universal Time (UTC), and also use the
24-hour clock (where 00:00 = midnight UTC).[9] The National Hurricane Center uses both UTC and the time zone where the center of the tropical cyclone is currently located. The time zones utilized (east to west) are:
Greenwich,
Cape Verde,
Atlantic,
Eastern, and
Central.[10] In this timeline, all information is listed by UTC first, with the respective regional time zone included in parentheses. Additionally, figures for
maximum sustained winds and position estimates are rounded to the nearest 5 units (
knots,
miles, or
kilometers), following National Hurricane Center practice. Direct wind observations are rounded to the nearest whole number. Atmospheric pressures are listed to the nearest
millibar and nearest hundredth of an
inch of mercury.
12:00 UTC (8:00 a.m. AST) at 39°24′N62°42′W / 39.4°N 62.7°W / 39.4; -62.7 (Dolly transitions into tropical storm) – Subtropical Storm Dolly transitions into a tropical storm and simultaneously reaches its peak intensity with 45 mph (72 km/h) maximum sustained winds and minimum barometric pressure of 1,000 mbar (30 inHg), while located about 370 mi (600 km) south-southeast of Halifax.[14]
06:00 UTC (2:00 a.m. AST) at 9°42′N46°36′W / 9.7°N 46.6°W / 9.7; -46.6 – Tropical Storm Gonzalo reaches its peak intensity of 65 mph (105 km/h) maximum sustained winds and minimum barometric pressure of 997 mbar (hPa; 29.44 inHg), while located about 690 mi (1,110 km) east of the southern Windward Islands.[17]
18:00 UTC (1:00 p.m. CDT) at 26°54′N96°48′W / 26.9°N 96.8°W / 26.9; -96.8 – Hurricane Hanna attains its peak intensity with maximum sustained winds of 90 mph (140 km/h) and minimum barometric pressure of 973 mbar (28.7 inHg), just off the coast of
South Texas.[18]
12:00 UTC (7:00 a.m. CDT) at 24°18′N87°12′W / 24.3°N 87.2°W / 24.3; -87.2 (Marco becomes a hurricane) – Tropical Storm Marco strengthens to a Category 1 hurricane about 210 mi (340 km) northwest of the western tip of
Cuba, and simultaneously reaches its peak intensity with maximum sustained winds of 75 mph (120 km/h) and minimum pressure of 991 mbar (29.3 inHg).[25]
12:00 UTC (8:00 a.m. EDT) at 34°36′N73°42′W / 34.6°N 73.7°W / 34.6; -73.7 (Tropical Storm Omar forms) – Tropical Depression Fifteen strengthens into Tropical Storm Omar about 115 mi (185 km) southeast of Cape Hatteras, North Carolina, and simultaneously reaches its peak intensity with sustained winds of 40 mph (64 km/h) and a minimum pressure of 1,003 mbar (29.6 inHg).[26]
Five simultaneous tropical cyclones active in the Atlantic on September 14:
Sally (left),
Paulette (center left), Rene (center right),
Teddy (bottom right), and Vicky (far right)
12:00 UTC (8:00 a.m. AST) at 20°30′N30°48′W / 20.5°N 30.8°W / 20.5; -30.8 (Vicky at peak intensity) – Tropical Storm Vicky reaches its peak intensity with sustained winds of 50 mph (80 km/h) and a pressure of 1,001 mbar (29.6 inHg), about 435 mi (700 km) northwest of the northwesternmost of the Cabo Verde Islands.[33]
^Hurricanes reaching Category 3 (111 miles per hour (179 km/h)) and higher on the 5-level
Saffir–Simpson wind speed scale are considered major hurricanes.[4]
^According to the
NHC's protocol, a tropical cyclone that degenerates into a remnant low in one basin and regenerates in another is given a different name. Since Amanda, a
Pacific tropical storm, degenerated over
Central America, the regenerated Atlantic tropical cyclone was given the next
name on the Atlantic list, Cristobal.[13]
^Due to the threat the system posed as it formed to the countries and territories in the eastern
Caribbean, the National Hurricane Center initiated advisories on the system as Potential Tropical Cyclone Nine at 15:00 UTC (11:00 a.m. AST) on July 28.[19][20]
^At the time, the National Hurricane Center did not name the system at that point because it was unclear whether it had a well-defined low-level-circulation.[27] However, with the storm posing an imminent threat to
Central America, the National Hurricane Center initiated advisories on the system as Potential Tropical Cyclone Sixteen that day at 15:00 UTC (10:00 a.m. CDT).[28]
^The determination that the system had become a subtropical storm at around 06:00 UTC (6:00 a.m. GMT) on September 17 was made by the National Hurricane Center during post-storm analysis.[34] At the time, it was determined that Subtropical Storm Alpha had formed at 16:30 UTC (4:30 p.m. GMT) on September 18 as it was approaching the coast of
Portugal.[35]
^Operationally, the National Hurricane Center continued issuing advisories on Tropical Depression Eta due to uncertainties about whether or not the surface circulation had dissipated.[45][46]
^"Central America: Hurricanes Eta and Iota"(PDF). Humanitarian Situation Report No.7. Panama City, Panama:
UNICEF Latin America and Caribbean Regional Office. January 2021. Retrieved June 18, 2021.
The
2020 Atlantic hurricane season was the most active
Atlantic hurricane season on record in terms of number of
named storms. Additionally, it was as an above-average season for
tropical cyclones for the fifth consecutive year.[nb 2][2] The season officially began on June 1, 2020, and ended on November 30, 2020. These dates, adopted by convention, historically delimit the period each year when most Atlantic
tropical systems form.[3] However, storm formation is possible at any time of the year, as was the case this season, when its first two named storms,
Tropical Storm Arthur and
Tropical Storm Bertha, formed on May 16 and May 27, respectively. The final storm,
Hurricane Iota, dissipated on November 18.
Altogether, the season produced 31 tropical or
subtropical cyclones, all but one of which became a named storm. Of the 30 named storms, 14 became hurricanes, and seven further intensified into major hurricanes.[nb 3] It was the second and final season to use the
Greek letter storm naming system, the first being
2005.[5]Hurricane Laura produced catastrophic storm surge levels, heavy rainfall, and spawned over a dozen tornadoes after striking
Louisiana on August 27 with winds of 150 mph (240 km/h). The storm was responsible for 81 deaths and it caused over
US$19 billion in damage across the
Greater Antilles and the
Southern United States.[6] Causing significant late-season loss of life and widespread destruction were November hurricanes
Eta and Iota, which made landfall in
Central America as Category 4 storms just two weeks apart.[2] The storms left a toll of 184 deaths and 110 missing across the region, and thousands of families lost their homes and livelihoods.[7] In March 2021, the names Laura, Eta and Iota were
retired from reuse in the North Atlantic by the
World Meteorological Organization due to the extraordinary amount of damage and number of fatalities they caused.[8]
This timeline documents tropical cyclone formations, strengthening, weakening,
landfalls,
extratropical transitions, and dissipations during the season. It includes information that was not released throughout the season, meaning that data from post-storm reviews by the
National Hurricane Center, such as a storm that was not initially warned upon, has been included.
By convention, meteorologists use one
time zone when issuing forecasts and making observations:
Coordinated Universal Time (UTC), and also use the
24-hour clock (where 00:00 = midnight UTC).[9] The National Hurricane Center uses both UTC and the time zone where the center of the tropical cyclone is currently located. The time zones utilized (east to west) are:
Greenwich,
Cape Verde,
Atlantic,
Eastern, and
Central.[10] In this timeline, all information is listed by UTC first, with the respective regional time zone included in parentheses. Additionally, figures for
maximum sustained winds and position estimates are rounded to the nearest 5 units (
knots,
miles, or
kilometers), following National Hurricane Center practice. Direct wind observations are rounded to the nearest whole number. Atmospheric pressures are listed to the nearest
millibar and nearest hundredth of an
inch of mercury.
12:00 UTC (8:00 a.m. AST) at 39°24′N62°42′W / 39.4°N 62.7°W / 39.4; -62.7 (Dolly transitions into tropical storm) – Subtropical Storm Dolly transitions into a tropical storm and simultaneously reaches its peak intensity with 45 mph (72 km/h) maximum sustained winds and minimum barometric pressure of 1,000 mbar (30 inHg), while located about 370 mi (600 km) south-southeast of Halifax.[14]
06:00 UTC (2:00 a.m. AST) at 9°42′N46°36′W / 9.7°N 46.6°W / 9.7; -46.6 – Tropical Storm Gonzalo reaches its peak intensity of 65 mph (105 km/h) maximum sustained winds and minimum barometric pressure of 997 mbar (hPa; 29.44 inHg), while located about 690 mi (1,110 km) east of the southern Windward Islands.[17]
18:00 UTC (1:00 p.m. CDT) at 26°54′N96°48′W / 26.9°N 96.8°W / 26.9; -96.8 – Hurricane Hanna attains its peak intensity with maximum sustained winds of 90 mph (140 km/h) and minimum barometric pressure of 973 mbar (28.7 inHg), just off the coast of
South Texas.[18]
12:00 UTC (7:00 a.m. CDT) at 24°18′N87°12′W / 24.3°N 87.2°W / 24.3; -87.2 (Marco becomes a hurricane) – Tropical Storm Marco strengthens to a Category 1 hurricane about 210 mi (340 km) northwest of the western tip of
Cuba, and simultaneously reaches its peak intensity with maximum sustained winds of 75 mph (120 km/h) and minimum pressure of 991 mbar (29.3 inHg).[25]
12:00 UTC (8:00 a.m. EDT) at 34°36′N73°42′W / 34.6°N 73.7°W / 34.6; -73.7 (Tropical Storm Omar forms) – Tropical Depression Fifteen strengthens into Tropical Storm Omar about 115 mi (185 km) southeast of Cape Hatteras, North Carolina, and simultaneously reaches its peak intensity with sustained winds of 40 mph (64 km/h) and a minimum pressure of 1,003 mbar (29.6 inHg).[26]
Five simultaneous tropical cyclones active in the Atlantic on September 14:
Sally (left),
Paulette (center left), Rene (center right),
Teddy (bottom right), and Vicky (far right)
12:00 UTC (8:00 a.m. AST) at 20°30′N30°48′W / 20.5°N 30.8°W / 20.5; -30.8 (Vicky at peak intensity) – Tropical Storm Vicky reaches its peak intensity with sustained winds of 50 mph (80 km/h) and a pressure of 1,001 mbar (29.6 inHg), about 435 mi (700 km) northwest of the northwesternmost of the Cabo Verde Islands.[33]
^Hurricanes reaching Category 3 (111 miles per hour (179 km/h)) and higher on the 5-level
Saffir–Simpson wind speed scale are considered major hurricanes.[4]
^According to the
NHC's protocol, a tropical cyclone that degenerates into a remnant low in one basin and regenerates in another is given a different name. Since Amanda, a
Pacific tropical storm, degenerated over
Central America, the regenerated Atlantic tropical cyclone was given the next
name on the Atlantic list, Cristobal.[13]
^Due to the threat the system posed as it formed to the countries and territories in the eastern
Caribbean, the National Hurricane Center initiated advisories on the system as Potential Tropical Cyclone Nine at 15:00 UTC (11:00 a.m. AST) on July 28.[19][20]
^At the time, the National Hurricane Center did not name the system at that point because it was unclear whether it had a well-defined low-level-circulation.[27] However, with the storm posing an imminent threat to
Central America, the National Hurricane Center initiated advisories on the system as Potential Tropical Cyclone Sixteen that day at 15:00 UTC (10:00 a.m. CDT).[28]
^The determination that the system had become a subtropical storm at around 06:00 UTC (6:00 a.m. GMT) on September 17 was made by the National Hurricane Center during post-storm analysis.[34] At the time, it was determined that Subtropical Storm Alpha had formed at 16:30 UTC (4:30 p.m. GMT) on September 18 as it was approaching the coast of
Portugal.[35]
^Operationally, the National Hurricane Center continued issuing advisories on Tropical Depression Eta due to uncertainties about whether or not the surface circulation had dissipated.[45][46]
^"Central America: Hurricanes Eta and Iota"(PDF). Humanitarian Situation Report No.7. Panama City, Panama:
UNICEF Latin America and Caribbean Regional Office. January 2021. Retrieved June 18, 2021.