NOAA's National Centers for Environmental Information
Summary
A total of 88 named storms occurred across the globe in 2022, which was near the 1991-2020 average. Of those, 40 reached tropical cyclone strength (≥74 mph), and 17 reached major tropical cyclone strength (≥111 mph). Both of these counts were below their 1991-2020 averages. The global accumulated cyclone energy (ACE: an integrated metric of the strength, frequency, and duration of tropical storms) was the lowest since 2010 and the fourth lowest since 1981. No basin was more active than normal in terms of ACE. The North Atlantic, East Pacific, and South Indian basins had near normal activity. The other basins were all less active than normal, including the West Pacific, which had its third season in a row with below normal activity. The only two storms to reach Saffir-Simpson hurricane wind scale category 5 (≥157 mph) during 2022 were both from the West Pacific: Super Typhoons Hinnamnor and Noru. This was the fewest number of category 5 storms globally since 2008.
Satellite image of Hurricane Ian.
Source: NOAA/CIRA
The North Atlantic hurricane activity was near its 1991-2020 average. However, both the 14 named storms and the ACE were their lowest values since 2015. Hurricane Fiona brought massive flooding to Puerto Rico, with some areas receiving 12-18 inches of rain. One station reported more than two feet of rain in a 24-hour period. After its extratropical transition, Fiona ultimately made landfall in Nova Scotia as the strongest and costliest post-tropical cyclone on record for Canada. Hurricane Ian made landfall in southwestern Florida shortly after achieving a peak intensity of 155 mph, just shy of category 5 strength (≥157 mph). Ian was the third costliest U.S. hurricane on record behind Katrina and Harvey. Just a few weeks later, Hurricane Nicole made landfall in eastern Florida with heavy rain and flooding. Nicole was the first hurricane to make landfall in Florida during November since Kate in 1985.
The East Pacific activity for 2022 was near its 1991-2020 average. It included Hurricanes Bonnie and Julia, both of which formed in the Atlantic before crossing Central America into the East Pacific. Four East Pacific storms made landfall in Mexico at hurricane strength in 2022: Agatha, Kay, Orlene, and Roslyn. Orlene and Roslyn made landfall in the same part of the Mexican coast just three weeks apart. Roslyn was the strongest East Pacific landfall since Hurricane Patricia in 2015.
The West Pacific was less active than its 1991-2020 average by most metrics for the third year in a row. However, the West Pacific produced the only two category 5 storms that occurred globally in 2022. Both of these typhoons, Hinnamnor and Noru, occurred during an active period from late August through September. Hinnamnor weakened as it approached South Korea but still made landfall as a category 2 typhoon and one of the strongest in history there. Noru caused severe damage to the Philippines and Southeast Asia. Typhoon Nanmadol had peak winds of 155 mph, just shy of category 5 strength. It weakened before making landfall in Japan, but still produced significant flooding. The post-tropical remnants of Typhoon Merbok caused hurricane strength winds and coastal flooding in the Aleutians and western Alaska.
The seven named storms in the North Indian Ocean was above its 1991-2020 average. However, only one of these achieved cyclone strength, Asani, and none reached major cyclone strength. As a result, the ACE was below its 1991-2020 average.
The tropical cyclone seasons in the Southern Hemisphere basins begin in July and end in June, so the seasons summarized here are the 2021/22 seasons that ended in June 2022. It is also more common for storms to cross basins in the Southern Hemisphere, so some storms are counted in multiple basins. The South Indian Ocean tropical cyclone activity was near normal in term of ACE. However, all five storms that reached cyclone strength also became major cyclones, and Madagascar was affected by an unprecedented six tropical cyclones. The strongest was Major Cyclone Batsirai, which caused widespread wind damage, power outages, and flooding.
The Australian region was less active than normal in terms of ACE and the quietest since 2015/16. Despite a normal number of named storms and cyclones, Vernon was the only storm to achieve major cyclone intensity. The Southwest Pacific was similarly quiet with no major cyclones for the first time since 2008/09.
North Atlantic
| Name |
Maximum CategoryMax Cat |
Dates >39 mph |
Maximum Sustained Winds | Minimum Central Pressure |
|---|---|---|---|---|
 | TS | June 5Jun 5-6 | 70 mph | 984 mb |
 | 3 | July 1Jul 1-9 | 115 mph† | 964 mb† |
 | TS | July 2Jul 2 | 40 mph | 1012 mb |
 | 1 | September 1Sep 1-8 | 90 mph | 972 mb |
 | 2 | September 3Sep 3-10 | 105 mph | 954 mb |
 | 4 | September 14Sep 14-23 | 130 mph | 932 mb |
 | TS | September 20Sep 20-26 | 65 mph | 995 mb |
 | TS | September 23Sep 23-24 | 40 mph | 1002 mb |
 | 4 | September 24Sep 24-30 | 155 mph | 937 mb |
 | 1 | October 7Oct 7-10 | 85 mph | 982 mb |
 | TS | October 11Oct 11-14 | 60 mph | 999 mb |
 | 1 | October 31-November 3Oct 31-Nov 3 | 80 mph | 988 mb |
 | 1 | November 1Nov 1-3 | 85 mph | 955 mb |
 | 1 | November 7Nov 7-11 | 75 mph | 980 mb |
| †Value occurred in the Eastern North Pacific | ||||
| Storm Type | Count | 1991-2020 Mean |
1981-2022 Rank* |
1851-2022 Record |
|---|---|---|---|---|
| Tropical Storm Winds ≥ 39 mph (34 kts) | 14 | 14.4 | 18th (tied with 3 other seasons) | 30 (2020) |
| Hurricane Winds ≥ 74 mph (64 kts) | 8 | 7.2 | 11th (tied with 5 other seasons) | 15 (2005) |
| Major Hurricane Winds ≥ 111 mph (96 kts) | 2 | 3.2 | 21st (tied with 10 other seasons) | 7 (2005, 2020) |
| Accumulated Cyclone Energy ACE×10⁴ kt² | 95.0 | 122.5 | 24th | 258.6 (1933) |
East Pacific
| Name |
Maximum CategoryMax Cat |
Dates >39 mph |
Maximum Sustained Winds | Minimum Central Pressure |
|---|---|---|---|---|
 | 2 | May 28May 28-31 | 110 mph | 964 mb |
 | 1 | June 14Jun 14-20 | 85 mph | 980 mb |
 | TS | June 17Jun 17-28 | 65 mph | 993 mb |
| 3 | July 1Jul 1-9 | 115 mph | 964 mb |
 | 4 | July 9Jul 9-17 | 140 mph | 954 mb |
 | 1 | July 16Jul 16-21 | 85 mph | 984 mb |
 | 1 | July 26-August 2Jul 26-Aug 2 | 90 mph | 975 mb |
 | TS | July 27Jul 27-31 | 60 mph | 997 mb |
 | 1 | August 7Aug 7-10 | 85 mph | 983 mb |
 | TS | August 15Aug 15 | 40 mph | 1005 mb |
 | TS | September 2Sep 2-4 | 50 mph | 999 mb |
 | 2 | September 4Sep 4-10 | 105 mph | 967 mb |
 | TS | September 16Sep 16-17 | 45 mph | 1002 mb |
 | TS | September 18Sep 18-20 | 65 mph | 992 mb |
 | TS | September 21Sep 21-24 | 65 mph | 996 mb |
 | 4 | September 29-October 3Sep 29-Oct 3 | 130 mph | 949 mb |
 | TS | October 3Oct 3-5 | 45 mph | 1004 mb |
| 1 | October 7Oct 7-10 | 85 mph‡ | 982 mb‡ |
 | 4 | October 20Oct 20-23 | 130 mph | 954 mb |
| ‡Value occurred in the North Atlantic | ||||
| Storm Type | Count | 1991-2020 Mean |
1981-2022 Rank* |
1949-2022 Record |
|---|---|---|---|---|
| Tropical Storm Winds ≥ 39 mph (34 kts) | 19 | 17.0 | 16th (tied with 4 other seasons) | 27 (1992) |
| Hurricane Winds ≥ 74 mph (64 kts) | 10 | 8.8 | 13th (tied with 5 other seasons) | 16 (1990, 1992, 2014, 2015) |
| Major Hurricane Winds ≥ 111 mph (96 kts) | 4 | 4.6 | 21st (tied with 4 other seasons) | 11 (2015) |
| Accumulated Cyclone Energy ACE×10⁴ kt² | 117.0 | 132.8 | 21st | 318.1 (2018) |
West Pacific
| Name |
Maximum CategoryMax Cat |
Dates >39 mph |
Maximum Sustained Winds | Minimum Central Pressure |
|---|---|---|---|---|
 | 4 | April 7Apr 7-15 | 130 mph | 939 mb |
 | TS | April 10Apr 10 | 45 mph | 999 mb |
 | 1 | June 30-July 2Jun 30-Jul 2 | 85 mph | 969 mb |
 | TS | July 1Jul 1-8 | 50 mph | 988 mb |
 | TS | August 11Aug 11-14 | 45 mph | 990 mb |
 | TS | August 22Aug 22-25 | 70 mph | 985 mb |
 | 2 | August 22Aug 22-25 | 105 mph | 956 mb |
 | 5 | August 28-September 6Aug 28-Sep 6 | 160 mph | 915 mb |
 | 4 | September 7Sep 7-16 | 130 mph | 942 mb |
 | 1 | September 11Sep 11-14 | 80 mph | 976 mb |
 | 4 | September 13Sep 13-19 | 155 mph | 917 mb |
 | 5 | September 22Sep 22-28 | 160 mph | 919 mb |
 | 1 | September 26Sep 26-29 | 75 mph | 970 mb |
 | 2 | September 28-October 3Sep 28-Oct 3 | 95 mph | 975 mb |
 | TS | October 14Oct 14 | 45 mph | 999 mb |
 | TS | October 14Oct 14 | 40 mph | 998 mb |
 | 2 | October 15Oct 15-20 | 100 mph | 964 mb |
 | TS | October 18Oct 18 | 40 mph | 1004 mb |
 | 1 | October 27-November 2Oct 27-Nov 2 | 80 mph | 979 mb |
 | TS | October 31Oct 31 | 40 mph | 1000 mb |
 | TS | November 12Nov 12-13 | 40 mph | 1000 mb |
 | TS | December 11Dec 11-12 | 60 mph | 992 mb |
| Storm Type | Count | 1991-2020 Mean |
1981-2022 Rank* |
1945-2022 Record |
|---|---|---|---|---|
| Tropical Storm Winds ≥ 39 mph (34 kts) | 22 | 26.3 | 35th (tied with 3 other seasons) | 38 (1964) |
| Typhoon Winds ≥ 74 mph (64 kts) | 12 | 16.1 | 34th (tied with 3 other seasons) | 26 (1964) |
| Major Typhoon Winds ≥ 111 mph (96 kts) | 5 | 9.4 | 37th (tied with 2 other seasons) | 16 (2015) |
| Accumulated Cyclone Energy ACE×10⁴ kt² | 160.6 | 299.7 | 37th | 588.3 (1997) |
North Indian
| Name |
Maximum CategoryMax Cat |
Dates >39 mph |
Maximum Sustained Winds | Minimum Central Pressure |
|---|---|---|---|---|
 | TS | March 4Mar 4-5 | 40 mph | 996 mb |
 | 1 | May 7May 7-11 | 75 mph | 976 mb |
 | TS | August 12Aug 12-13 | 40 mph | 989 mb |
 | TS | August 18Aug 18-19 | 50 mph | 990 mb |
 | TS | October 23Oct 23-24 | 50 mph | 994 mb |
 | TS | December 8Dec 8-9 | 60 mph | 989 mb |
 | TS | December 15Dec 15-16 | 50 mph | 999 mb |
| Storm Type | Count | 1991-2020 Mean |
1981-2022 Rank* |
1972-2022 Record |
|---|---|---|---|---|
| Tropical Storm Winds ≥ 39 mph (34 kts) | 7 | 5.5 | 6th (tied with 2 other seasons) | 11 (1992) |
| Cyclone Winds ≥ 74 mph (64 kts) | 1 | 2.1 | 23rd (tied with 12 other seasons) | 6 (2019) |
| Major Cyclone Winds ≥ 111 mph (96 kts) | 0 | 1.1 | 26th (tied with 16 other seasons) | 5 (2019) |
| Accumulated Cyclone Energy ACE×10⁴ kt² | 10.6 | 24.6 | 34th | 93.0 (2019) |
South Indian
| Name |
Maximum CategoryMax Cat |
Dates >39 mph |
Maximum Sustained Winds | Minimum Central Pressure |
|---|---|---|---|---|
 | TS | January 23Jan 23-24 | 60 mph | 993 mb |
 | 4 | January 27-February 8Jan 27-Feb 8 | 145 mph | 932 mb |
 | TS | February 4Feb 4-6 | 50 mph | 992 mb |
 | TS | February 13Feb 13-15 | 60 mph | 995 mb |
 | 4 | February 16Feb 16-24 | 130 mph | 941 mb |
 | 4 | February 25-March 3Feb 25-Mar 3 | 130 mph | 946 mb |
 | 3 | March 8Mar 8-12 | 115 mph | 959 mb |
 | 4 | March 23-April 1Mar 23-Apr 1 | 135 mph | 938 mb |
 | TS | April 24Apr 24-27 | 60 mph | 984 mb |
| Storm Type | Count | 1991-2020 Mean |
1981-2022 Rank* |
1956-2022 Record |
|---|---|---|---|---|
| Tropical Storm Winds ≥ 39 mph (34 kts) | 9 | 10.5 | 31st (tied with 1 other season) | 16 (1997) |
| Cyclone Winds ≥ 74 mph (64 kts) | 5 | 6.1 | 26th (tied with 4 other seasons) | 11 (2019) |
| Major Cyclone Winds ≥ 111 mph (96 kts) | 5 | 3.5 | 5th (tied with 1 other season) | 9 (2019) |
| Accumulated Cyclone Energy ACE×10⁴ kt² | 88.8 | 94.3 | 24th | 186.9 (1994) |
Australia
| Name |
Maximum CategoryMax Cat |
Dates >39 mph |
Maximum Sustained Winds | Minimum Central Pressure |
|---|---|---|---|---|
 | TS | November 22Nov 22-24 | 45 mph | 988 mb |
 | TS | December 1Dec 1-9 | 40 mph | 999 mb |
 | 1 | December 11Dec 11-15 | 80 mph | 980 mb |
 | TS | December 31-January 1Dec 31-Jan 1 | 65 mph | 988 mb |
 | 1 | January 9Jan 9-12 | 75 mph | 986 mb |
 | TS | January 31-February 1Jan 31-Feb 1 | 40 mph | 998 mb |
| 4 | February 25-March 3Feb 25-Mar 3 | 130 mph‖ | 946 mb‖ |
 | TS | February 25-March 2Feb 25-Mar 2 | 60 mph | 988 mb |
 | TS | March 2Mar 2 | 40 mph | 1001 mb |
 | TS | March 13Mar 13-17 | 70 mph | 989 mb |
 | 2 | March 20Mar 20-24 | 100 mph | 967 mb |
 | TS | May 7May 7-11 | 70 mph | 982 mb |
| ‖Value occurred in the South Indian | ||||
| Storm Type | Count | 1991-2020 Mean |
1981-2022 Rank* |
1956-2022 Record |
|---|---|---|---|---|
| Tropical Storm Winds ≥ 39 mph (34 kts) | 12 | 10.7 | 11th (tied with 5 other seasons) | 19 (1999) |
| Tropical Cyclone Winds ≥ 74 mph (64 kts) | 4 | 4.8 | 21st (tied with 4 other seasons) | 9 (1992, 1996) |
| Major Tropical Cyclone Winds ≥ 111 mph (96 kts) | 1 | 2.4 | 24th (tied with 12 other seasons) | 6 (2015) |
| Accumulated Cyclone Energy ACE×10⁴ kt² | 26.5 | 59.5 | 38th | 111.3 (1999) |
Southwest Pacific
| Name |
Maximum CategoryMax Cat |
Dates >39 mph |
Maximum Sustained Winds | Minimum Central Pressure |
|---|---|---|---|---|
| 1 | December 11Dec 11-15 | 80 mph** | 980 mb** |
 | TS | January 10Jan 10-15 | 60 mph | 980 mb |
 | 2 | February 9Feb 9-12 | 100 mph | 956 mb |
 | TS | March 3Mar 3-4 | 45 mph | 987 mb |
 | TS | April 4Apr 4-8 | 60 mph | 989 mb |
 | TS | May 18May 18-22 | 40 mph | 1002 mb |
| **Value occurred in the Southwest Pacific | ||||
| Storm Type | Count | 1991-2020 Mean |
1981-2022 Rank* |
1956-2022 Record |
|---|---|---|---|---|
| Tropical Storm Winds ≥ 39 mph (34 kts) | 6 | 7.1 | 17th (tied with 9 other seasons) | 16 (1998) |
| Tropical Cyclone Winds ≥ 74 mph (64 kts) | 2 | 3.8 | 28th (tied with 8 other seasons) | 10 (1998) |
| Major Tropical Cyclone Winds ≥ 111 mph (96 kts) | 0 | 1.9 | 34th (tied with 8 other seasons) | 6 (2003) |
| Accumulated Cyclone Energy ACE×10⁴ kt² | 18.8 | 50.4 | 33rd | 128.8 (1998) |
Global
| Name |
Maximum CategoryMax Cat |
Dates >39 mph |
Maximum Sustained Winds | Minimum Central Pressure |
|---|---|---|---|---|
| TS | December 31-January 1Dec 31-Jan 1 | 65 mph | 988 mb |
| 1 | January 9Jan 9-12 | 75 mph | 986 mb |
| TS | January 10Jan 10-15 | 60 mph | 980 mb |
| TS | January 23Jan 23-24 | 60 mph | 993 mb |
| 4 | January 27-February 8Jan 27-Feb 8 | 145 mph | 932 mb |
| TS | January 31-February 1Jan 31-Feb 1 | 40 mph | 998 mb |
| TS | February 4Feb 4-6 | 50 mph | 992 mb |
| 2 | February 9Feb 9-12 | 100 mph | 956 mb |
| TS | February 13Feb 13-15 | 60 mph | 995 mb |
| 4 | February 16Feb 16-24 | 130 mph | 941 mb |
| 4 | February 25-March 3Feb 25-Mar 3 | 130 mph | 946 mb |
| TS | February 25-March 2Feb 25-Mar 2 | 60 mph | 988 mb |
| TS | March 2Mar 2 | 40 mph | 1001 mb |
| TS | March 3Mar 3-4 | 45 mph | 987 mb |
| TS | March 4Mar 4-5 | 40 mph | 996 mb |
| 3 | March 8Mar 8-12 | 115 mph | 959 mb |
| TS | March 13Mar 13-17 | 70 mph | 989 mb |
| 2 | March 20Mar 20-24 | 100 mph | 967 mb |
| 4 | March 23-April 1Mar 23-Apr 1 | 135 mph | 938 mb |
| TS | April 4Apr 4-8 | 60 mph | 989 mb |
| 4 | April 7Apr 7-15 | 130 mph | 939 mb |
| TS | April 10Apr 10 | 45 mph | 999 mb |
| TS | April 24Apr 24-27 | 60 mph | 984 mb |
| 1 | May 7May 7-11 | 75 mph | 976 mb |
| TS | May 7May 7-11 | 70 mph | 982 mb |
| TS | May 18May 18-22 | 40 mph | 1002 mb |
| 2 | May 28May 28-31 | 110 mph | 964 mb |
| TS | June 5Jun 5-6 | 70 mph | 984 mb |
| 1 | June 14Jun 14-20 | 85 mph | 980 mb |
| TS | June 17Jun 17-28 | 65 mph | 993 mb |
| 1 | June 30-July 2Jun 30-Jul 2 | 85 mph | 969 mb |
| 3 | July 1Jul 1-9 | 115 mph | 964 mb |
| TS | July 1Jul 1-8 | 50 mph | 988 mb |
| TS | July 2Jul 2 | 40 mph | 1012 mb |
| 4 | July 9Jul 9-17 | 140 mph | 954 mb |
| 1 | July 16Jul 16-21 | 85 mph | 984 mb |
| 1 | July 26-August 2Jul 26-Aug 2 | 90 mph | 975 mb |
| TS | July 27Jul 27-31 | 60 mph | 997 mb |
 | TS | July 29Jul 29-31 | 50 mph | 995 mb |
| 1 | August 7Aug 7-10 | 85 mph | 983 mb |
| TS | August 11Aug 11-14 | 45 mph | 990 mb |
| TS | August 12Aug 12-13 | 40 mph | 989 mb |
| TS | August 15Aug 15 | 40 mph | 1005 mb |
| TS | August 18Aug 18-19 | 50 mph | 990 mb |
| TS | August 22Aug 22-25 | 70 mph | 985 mb |
| 2 | August 22Aug 22-25 | 105 mph | 956 mb |
| 5 | August 28-September 6Aug 28-Sep 6 | 160 mph | 915 mb |
| 1 | September 1Sep 1-8 | 90 mph | 972 mb |
| TS | September 2Sep 2-4 | 50 mph | 999 mb |
| 2 | September 3Sep 3-10 | 105 mph | 954 mb |
| 2 | September 4Sep 4-10 | 105 mph | 967 mb |
| 4 | September 7Sep 7-16 | 130 mph | 942 mb |
| 1 | September 11Sep 11-14 | 80 mph | 976 mb |
| 4 | September 13Sep 13-19 | 155 mph | 917 mb |
| 4 | September 14Sep 14-23 | 130 mph | 932 mb |
| TS | September 16Sep 16-17 | 45 mph | 1002 mb |
| TS | September 18Sep 18-20 | 65 mph | 992 mb |
| TS | September 20Sep 20-26 | 65 mph | 995 mb |
| TS | September 21Sep 21-24 | 65 mph | 996 mb |
| 5 | September 22Sep 22-28 | 160 mph | 919 mb |
| TS | September 23Sep 23-24 | 40 mph | 1002 mb |
| 4 | September 24Sep 24-30 | 155 mph | 937 mb |
| 1 | September 26Sep 26-29 | 75 mph | 970 mb |
 | TS | September 26Sep 26-27 | 45 mph | 998 mb |
| 2 | September 28-October 3Sep 28-Oct 3 | 95 mph | 975 mb |
| 4 | September 29-October 3Sep 29-Oct 3 | 130 mph | 949 mb |
| TS | October 3Oct 3-5 | 45 mph | 1004 mb |
 | TS | October 6Oct 6-9 | 45 mph | 998 mb |
| 1 | October 7Oct 7-10 | 85 mph | 982 mb |
| TS | October 11Oct 11-14 | 60 mph | 999 mb |
| TS | October 14Oct 14 | 45 mph | 999 mb |
| TS | October 14Oct 14 | 40 mph | 998 mb |
| 2 | October 15Oct 15-20 | 100 mph | 964 mb |
| TS | October 18Oct 18 | 40 mph | 1004 mb |
| 4 | October 20Oct 20-23 | 130 mph | 954 mb |
| TS | October 23Oct 23-24 | 50 mph | 994 mb |
| 1 | October 27-November 2Oct 27-Nov 2 | 80 mph | 979 mb |
| 1 | October 31-November 3Oct 31-Nov 3 | 80 mph | 988 mb |
| TS | October 31Oct 31 | 40 mph | 1000 mb |
| 1 | November 1Nov 1-3 | 85 mph | 955 mb |
 | TS | November 3Nov 3-5 | 40 mph | 1004 mb |
| 1 | November 7Nov 7-11 | 75 mph | 980 mb |
| TS | November 12Nov 12-13 | 40 mph | 1000 mb |
| TS | December 8Dec 8-9 | 60 mph | 989 mb |
| TS | December 11Dec 11-12 | 60 mph | 992 mb |
| TS | December 15Dec 15-16 | 50 mph | 999 mb |
 | 4 | December 18Dec 18-31 | 155 mph | 922 mb |
 | TS | December 22Dec 22 | 45 mph | 994 mb |
| Storm Type | Count | 1991-2020 Mean |
1981-2022 Rank* |
1972-2022 Record |
|---|---|---|---|---|
| Tropical Storm Winds ≥ 39 mph (34 kts) | 88 | 88.0 | 18th (tied with 1 other season) | 106 (2020) |
| Tropical Cyclone Winds ≥ 74 mph (64 kts) | 40 | 47.8 | 33rd (tied with 1 other season) | 59 (1990, 2018) |
| Major Tropical Cyclone Winds ≥ 111 mph (96 kts) | 17 | 25.7 | 38th (tied with 1 other season) | 39 (2015) |
| Accumulated Cyclone Energy ACE×10⁴ kt² | 556.6 | 784.3 | 39th | 1,148.5 (1992) |
Data Description
The data in this report are derived from NCEI's IBTrACS dataset (Knapp et al. 2010; Schreck et al. 2014). IBTrACS tropical cyclone track and intensity data from agencies and sources around the globe. In this report, data from NOAA's National Hurricane Center (NHC) are used for the North Atlantic and East Pacific. The other basins use data from the U.S. Military's Joint Typhoon Warning Center (JTWC).
Historical values use the "best track" data that have been analyzed by forecasters after the season using all available data. Operational procedures and observing systems have changed with time and between regions, which makes these data heterogeneous. Intensity data are generally the most reliable since the early 1970s in the Atlantic (Landsea and Franklin 2013) and since the mid-1980s in other regions (Chu et al. 2002). The number of short-lived storms (≤2 days) has also increased since around 2000 due to improvements in observations and analysis techniques (Landsea et al. 2010).
Values for the current year are provisional values from the operational forecast advisories. IBTrACS obtains these from NCEP's TC Vitals, the NCAR Tropical Cyclone Guidance Project, and NHC provisional data. These values are subject to change during the post-season best track analysis. They also only include 6-hourly storm fixes, which means they may miss special advisories at landfall, peak intensity, etc.
The tropical cyclone seasons in the Southern Hemisphere begin in July and end in June, while the Northern Hemisphere seasons are counted from January to December. Storms are counted in all basins, months, and years in which they occur, which means some storms may appear more than once. However, the global totals only include each storm one time.
References
- Chu, J.-H., C. R. Sampson, A. S. Levine, and E. Fukada, 2002: The joint typhoon warning center tropical cyclone best-tracks, 1945–2000. Naval Research Laboratory, Reference Number NRL/MR/7540-02-16, 22 pp., https://www.metoc.navy.mil/jtwc/products/best-tracks/tc-bt-report.html.
- Knapp, K. R., M. C. Kruk, D. H. Levinson, H. J. Diamond, and C. J. Neumann, 2010: The International Best Track Archive for Climate Stewardship (IBTrACS). Bull. Amer. Meteor. Soc., 91, 363–376, https://doi.org/10.1175/2009BAMS2755.1.
- Landsea, C. W., and J. L. Franklin, 2013: Atlantic Hurricane database uncertainty and presentation of a new database format. Mon. Wea. Rev., 141, 3576–3592, https://doi.org/10.1175/MWR-D-12-00254.1.
- ——, G. A. Vecchi, L. Bengtsson, and T. R. Knutson, 2010: Impact of duration thresholds on Atlantic tropical cyclone counts. J. Climate, 23, 2508–2519, https://doi.org/10.1175/2009JCLI3034.1.
- Schreck, C. J., K. R. Knapp, and J. P. Kossin, 2014: The Impact of Best Track Discrepancies on Global Tropical Cyclone Climatologies using IBTrACS. Mon. Wea. Rev., 142, 3881–3899, https://doi.org/10.1175/MWR-D-14-00021.1.