May 2024: Weather Records and Temperatures Against Normal
May 2024 is settled: the figures use data received up to 9 November 2026, more than 45 days after the month ended, so the late station reports are in. This page compares May 2024 at weather stations worldwide with each station's own 1991 to 2020 May normal, ranks it against May of every year since 1951, and lists the weather records, events and storms of the month.
Data as of . Last revised (2026-11-09).
Key Facts
- May 2024 is settled; its data run to 9 November 2026.
- In May 2024, stations worldwide averaged +0.7 C (+1.2 F) against their 1991 to 2020 May normals, the warmest May in 74 ranked years from 1951 to 2024.
- The mean daily maximum in May 2024 was +0.8 C (+1.4 F) against normal and the mean daily minimum +0.6 C (+1.0 F).
- Among the continents in May 2024, Africa was the warmest against normal, at +1.5 C (+2.8 F), and Europe the coolest, at +0.2 C (+0.4 F).
- The station furthest above its May normal in May 2024 was Sylarna (Sweden), at +6.4 C (+11.5 F); the furthest below was Troicko-Pecherskoe (Russia), at -5.4 C (-9.8 F).
- Of the 8,614 stations with a full month of rain data in May 2024, 23% had less than half their normal May rain and 11% had at least twice their normal; the median station had 95% of its normal.
- 21,788 weather records were set or tied in May 2024, including 12,014 record highs and 3,951 record lows of maximum and minimum temperature, and 106 all-time records.
- In May 2024, 75% of the daily temperature records were record highs (3.0 to 1 highs to lows), against an average of 64% for May in 2014 to 2023.
- 22 extreme weather events detected by this site overlapped May 2024.
- 5 named storms had a best track position in May 2024; 3 peaked at 64 kt (119 km/h, 74 mph) or more and 0 at 96 kt (178 km/h, 110 mph) or more over their lifetime.
- The Oceanic Nino Index for AMJ 2024, the three months centred on May 2024, was +0.43: neutral, outside any El Nino or La Nina episode. NOAA's relative index (RONI) for the same season was -0.28.
- Monthly mean extent in May 2024: Arctic sea ice 12.74 million sq km (4.92 million sq mi), the 12th lowest of 46 years for May; Antarctic sea ice 9.36 million sq km (3.62 million sq mi), the 8th lowest of 46 years for May.
- Carbon dioxide at Mauna Loa averaged 426.90 ppm in May 2024, 2.90 ppm more than in May 2023.
Temperature Against Normal
May 2024, against 1991 to 2020| Band | Stations on the map |
|---|---|
| More than 3 C (5.4 F) below normal | 36 |
| 1 to 3 C (1.8 to 5.4 F) below normal | 219 |
| Within 1 C (1.8 F) of normal | 1,028 |
| 1 to 3 C (1.8 to 5.4 F) above normal | 794 |
| More than 3 C (5.4 F) above normal | 203 |
| Area | Stations | Daily maximum vs normal | Daily minimum vs normal | Mean vs normal | Rank for May (1 is warmest) |
|---|---|---|---|---|---|
| World | 6,476 | +0.8 C (+1.4 F) | +0.6 C (+1.0 F) | +0.7 C (+1.2 F) | 1st of 74 |
| Africa | 69 | +1.8 C (+3.3 F) | +1.2 C (+2.2 F) | +1.5 C (+2.8 F) | 1st of 60 |
| Asia | 320 | +1.0 C (+1.8 F) | +0.5 C (+0.9 F) | +0.7 C (+1.3 F) | 3rd of 73 |
| Europe | 1,203 | +0.4 C (+0.8 F) | +0.0 C (+0.0 F) | +0.2 C (+0.4 F) | 17th of 74 |
| North America | 4,481 | +0.5 C (+0.9 F) | +0.8 C (+1.5 F) | +0.7 C (+1.2 F) | 2nd of 74 |
| Oceania | 400 | +0.6 C (+1.0 F) | +0.5 C (+1.0 F) | +0.6 C (+1.0 F) | 8th of 74 |
| South America | 3 | +1.6 C (+2.9 F) | +0.7 C (+1.2 F) | +1.1 C (+2.0 F) | 1st of 33 |
Stations are averaged in 5 degree grid cells and the cells are weighted by the cosine of their latitude. A value and a rank need cells holding at least 50% of the weight of every cell that has ever had data for May; n/a means fewer stations have reported so far. The world includes Antarctica and islands without a continent row.
| Year | Mean against the 1991 to 2020 normal |
|---|---|
| 1951 | -0.8 C (-1.4 F) |
| 1952 | -1.0 C (-1.8 F) |
| 1953 | -0.6 C (-1.1 F) |
| 1954 | -1.2 C (-2.2 F) |
| 1955 | -0.8 C (-1.5 F) |
| 1956 | -1.0 C (-1.8 F) |
| 1957 | -0.9 C (-1.6 F) |
| 1958 | -0.6 C (-1.2 F) |
| 1959 | -0.8 C (-1.5 F) |
| 1960 | -1.4 C (-2.5 F) |
| 1961 | -0.8 C (-1.4 F) |
| 1962 | -0.6 C (-1.1 F) |
| 1963 | -0.7 C (-1.2 F) |
| 1964 | -0.8 C (-1.5 F) |
| 1965 | -1.0 C (-1.7 F) |
| 1966 | -1.0 C (-1.8 F) |
| 1967 | -0.4 C (-0.7 F) |
| 1968 | -0.9 C (-1.6 F) |
| 1969 | -0.9 C (-1.6 F) |
| 1970 | -0.8 C (-1.5 F) |
| 1971 | -1.1 C (-1.9 F) |
| 1972 | -1.0 C (-1.7 F) |
| 1973 | -0.6 C (-1.2 F) |
| 1974 | -0.9 C (-1.6 F) |
| 1975 | -0.7 C (-1.2 F) |
| 1976 | -1.1 C (-1.9 F) |
| 1977 | -0.6 C (-1.0 F) |
| 1978 | -0.9 C (-1.6 F) |
| 1979 | -0.7 C (-1.3 F) |
| 1980 | -0.6 C (-1.1 F) |
| 1981 | -0.7 C (-1.2 F) |
| 1982 | -0.6 C (-1.2 F) |
| 1983 | -0.6 C (-1.1 F) |
| 1984 | -0.4 C (-0.7 F) |
| 1985 | -0.6 C (-1.2 F) |
| 1986 | -0.5 C (-0.9 F) |
| 1987 | -0.5 C (-0.9 F) |
| 1988 | -0.3 C (-0.5 F) |
| 1989 | -0.3 C (-0.6 F) |
| 1990 | -0.2 C (-0.3 F) |
| 1991 | -0.4 C (-0.7 F) |
| 1992 | -0.5 C (-0.9 F) |
| 1993 | -0.5 C (-0.9 F) |
| 1994 | -0.3 C (-0.6 F) |
| 1995 | -0.3 C (-0.6 F) |
| 1996 | -0.2 C (-0.3 F) |
| 1997 | -0.3 C (-0.5 F) |
| 1998 | -0.1 C (-0.1 F) |
| 1999 | -0.3 C (-0.6 F) |
| 2000 | -0.1 C (-0.2 F) |
| 2001 | +0.1 C (+0.2 F) |
| 2002 | -0.1 C (-0.1 F) |
| 2003 | +0.2 C (+0.3 F) |
| 2004 | -0.2 C (-0.3 F) |
| 2005 | +0.1 C (+0.2 F) |
| 2006 | -0.2 C (-0.3 F) |
| 2007 | +0.4 C (+0.7 F) |
| 2008 | -0.1 C (-0.3 F) |
| 2009 | 0.0 C (0.0 F) |
| 2010 | +0.3 C (+0.5 F) |
| 2011 | -0.1 C (-0.3 F) |
| 2012 | +0.4 C (+0.8 F) |
| 2013 | +0.3 C (+0.5 F) |
| 2014 | +0.4 C (+0.7 F) |
| 2015 | +0.4 C (+0.6 F) |
| 2016 | +0.5 C (+1.0 F) |
| 2017 | +0.1 C (+0.2 F) |
| 2018 | +0.5 C (+0.8 F) |
| 2019 | +0.2 C (+0.4 F) |
| 2020 | +0.4 C (+0.7 F) |
| 2021 | +0.4 C (+0.6 F) |
| 2022 | +0.3 C (+0.5 F) |
| 2023 | +0.1 C (+0.1 F) |
| 2024 | +0.7 C (+1.2 F) |
Furthest Above Normal
| Station | Country | Mean maximum | Maximum vs normal | Mean minimum | Minimum vs normal | Mean vs normal | Years of normal |
|---|---|---|---|---|---|---|---|
| Sylarna | Sweden | 12.8 C (55.0 F) | +7.3 C (+13.2 F) | 4.5 C (40.0 F) | +5.4 C (+9.8 F) | +6.4 C (+11.5 F) | 29 |
| Fokstua | Norway | 16.1 C (60.9 F) | +7.6 C (+13.6 F) | 4.2 C (39.6 F) | +4.5 C (+8.1 F) | +6.0 C (+10.9 F) | 30 |
| Klovsjohojden_A | Sweden | 16.2 C (61.2 F) | +7.0 C (+12.6 F) | 6.5 C (43.6 F) | +5.0 C (+9.1 F) | +6.0 C (+10.8 F) | 25 |
| Tannas A | Sweden | 18.0 C (64.4 F) | +7.0 C (+12.5 F) | 5.3 C (41.5 F) | +4.4 C (+7.8 F) | +5.7 C (+10.2 F) | 25 |
| Sandane | Norway | 21.4 C (70.5 F) | +7.1 C (+12.9 F) | 9.4 C (49.0 F) | +4.0 C (+7.1 F) | +5.6 C (+10.0 F) | 27 |
| Bergen/Flesland | Norway | 19.6 C (67.4 F) | +6.4 C (+11.5 F) | 10.7 C (51.3 F) | +4.7 C (+8.5 F) | +5.6 C (+10.0 F) | 30 |
| Vaernes | Norway | 21.0 C (69.7 F) | +7.2 C (+12.9 F) | 9.2 C (48.5 F) | +3.9 C (+7.0 F) | +5.5 C (+10.0 F) | 30 |
| Idre_Fjall_A | Sweden | 15.1 C (59.2 F) | +6.1 C (+11.0 F) | 6.2 C (43.1 F) | +4.8 C (+8.7 F) | +5.5 C (+9.9 F) | 29 |
| Bergen Florida | Norway | 21.2 C (70.1 F) | +6.2 C (+11.2 F) | 11.5 C (52.8 F) | +4.6 C (+8.3 F) | +5.4 C (+9.8 F) | 30 |
| Atorp | Sweden | 21.9 C (71.5 F) | +5.7 C (+10.3 F) | 9.7 C (49.5 F) | +5.0 C (+9.0 F) | +5.4 C (+9.7 F) | 30 |
Furthest Below Normal
| Station | Country | Mean maximum | Maximum vs normal | Mean minimum | Minimum vs normal | Mean vs normal | Years of normal |
|---|---|---|---|---|---|---|---|
| Troicko-Pecherskoe | Russia | 6.9 C (44.4 F) | -6.5 C (-11.8 F) | -2.6 C (27.4 F) | -4.3 C (-7.8 F) | -5.4 C (-9.8 F) | 29 |
| Kirov | Russia | 12.8 C (55.0 F) | -5.1 C (-9.2 F) | 0.7 C (33.3 F) | -5.7 C (-10.3 F) | -5.4 C (-9.8 F) | 30 |
| Aksakovo | Russia | 14.4 C (58.0 F) | -4.8 C (-8.6 F) | 1.3 C (34.4 F) | -5.8 C (-10.5 F) | -5.3 C (-9.6 F) | 30 |
| Leusi | Russia | 10.5 C (51.0 F) | -5.3 C (-9.6 F) | -0.4 C (31.3 F) | -5.2 C (-9.3 F) | -5.2 C (-9.4 F) | 30 |
| Ust Tzilma | Russia | 4.7 C (40.4 F) | -5.8 C (-10.5 F) | -3.5 C (25.7 F) | -4.4 C (-7.8 F) | -5.1 C (-9.2 F) | 30 |
| Glazov | Russia | 12.0 C (53.6 F) | -5.4 C (-9.8 F) | -0.1 C (31.8 F) | -4.7 C (-8.4 F) | -5.1 C (-9.1 F) | 25 |
| Ust-USA | Russia | 2.9 C (37.2 F) | -5.8 C (-10.4 F) | -4.7 C (23.6 F) | -4.3 C (-7.7 F) | -5.0 C (-9.0 F) | 29 |
| Petrun | Russia | 1.3 C (34.3 F) | -5.6 C (-10.2 F) | -6.6 C (20.2 F) | -4.1 C (-7.3 F) | -4.8 C (-8.7 F) | 29 |
| Ak-Bulak | Russia | 18.5 C (65.2 F) | -4.4 C (-8.0 F) | 3.7 C (38.7 F) | -5.1 C (-9.2 F) | -4.8 C (-8.6 F) | 30 |
| Vetluga | Russia | 14.4 C (57.8 F) | -4.4 C (-8.0 F) | 1.0 C (33.8 F) | -5.0 C (-9.0 F) | -4.7 C (-8.5 F) | 30 |
The lists use stations with at least 25 years behind their normal. One station does not stand for the area around it.
Countries
| Country | Stations | Mean vs normal |
|---|---|---|
| Sweden | 179 | +3.5 C (+6.3 F) |
| Estonia | 21 | +3.0 C (+5.5 F) |
| Norway | 72 | +2.8 C (+5.1 F) |
| South Africa | 21 | +2.4 C (+4.4 F) |
| Mexico | 12 | +2.4 C (+4.2 F) |
| Netherlands | 31 | +2.3 C (+4.2 F) |
| Finland | 122 | +2.3 C (+4.1 F) |
| United Kingdom | 56 | +2.1 C (+3.8 F) |
| Germany | 317 | +2.0 C (+3.6 F) |
| Algeria | 9 | +1.8 C (+3.2 F) |
| Niger | 10 | +1.7 C (+3.0 F) |
| Czech Republic | 6 | +1.5 C (+2.7 F) |
| China | 174 | +1.4 C (+2.4 F) |
| Belarus | 11 | +1.3 C (+2.3 F) |
| Morocco | 6 | +1.3 C (+2.3 F) |
| Puerto Rico [United States] | 15 | +1.3 C (+2.3 F) |
| Thailand | 25 | +1.2 C (+2.2 F) |
| Indonesia | 16 | +1.0 C (+1.9 F) |
| Italy | 6 | +0.8 C (+1.4 F) |
| India | 17 | +0.7 C (+1.3 F) |
| France | 47 | +0.6 C (+1.0 F) |
| Australia | 391 | +0.6 C (+1.0 F) |
| Kyrgyzstan | 5 | +0.4 C (+0.8 F) |
| United States | 4,440 | +0.4 C (+0.8 F) |
| Spain | 85 | +0.4 C (+0.7 F) |
| Ukraine | 26 | +0.1 C (+0.2 F) |
| Turkey | 10 | -0.1 C (-0.2 F) |
| Switzerland | 8 | -0.1 C (-0.2 F) |
| Iran | 5 | -0.3 C (-0.6 F) |
| Romania | 21 | -0.6 C (-1.1 F) |
| Russia | 156 | -0.7 C (-1.3 F) |
| Turkmenistan | 15 | -0.7 C (-1.3 F) |
| Uzbekistan | 15 | -0.8 C (-1.5 F) |
| Kazakhstan | 24 | -1.1 C (-1.9 F) |
Rain Against Normal
8,614 stations, May 2024| Band | Stations on the map |
|---|---|
| Under 50% of normal | 579 |
| 50 to 90% of normal | 519 |
| 90 to 110% of normal | 267 |
| 110 to 200% of normal | 613 |
| 200% or more of normal | 171 |
| Under 50% | |
|---|---|
| 50 to 90% | |
| 90 to 110% | |
| 110 to 200% | |
| 200% or more |
Of the 8,614 stations with a full month of rain data in May 2024, 23% had less than half their normal May rain and 11% had at least twice their normal; the median station had 95% of its normal. A station month needs 28 days of rain data, because a total from fewer days is too low, and a normal of at least 10 mm.
Wettest Against Normal
| Station | Country | Rain | Normal | Percent of normal | Years of normal |
|---|---|---|---|---|---|
| Moruya (the Lagoon) | Australia | 282.0 mm (11.1 in) | 46.7 mm (1.8 in) | 603% | 29 |
| Honolulu Intl AP | United States | 124.6 mm (4.9 in) | 20.8 mm (0.8 in) | 598% | 30 |
| Araluen Lower (Araluen Rd) | Australia | 209.0 mm (8.2 in) | 35.2 mm (1.4 in) | 595% | 26 |
| Wilhelmina Rise 721 | United States | 319.8 mm (12.6 in) | 54.6 mm (2.1 in) | 585% | 28 |
| Hillston Airport | Australia | 161.5 mm (6.4 in) | 28.4 mm (1.1 in) | 570% | 29 |
| Culburra Treatment Works | Australia | 480.6 mm (18.9 in) | 86.2 mm (3.4 in) | 558% | 28 |
| Huntsville | United States | 627.5 mm (24.7 in) | 113.5 mm (4.5 in) | 553% | 30 |
| Booligal (Belmont) | Australia | 133.2 mm (5.2 in) | 24.3 mm (1.0 in) | 547% | 29 |
| Batemans Bay - Buckenbowra | Australia | 226.7 mm (8.9 in) | 41.5 mm (1.6 in) | 546% | 30 |
| Wilcannia (Reid St) | Australia | 108.9 mm (4.3 in) | 20.0 mm (0.8 in) | 545% | 30 |
Driest Against Normal
| Station | Country | Rain | Normal | Percent of normal | Years of normal |
|---|---|---|---|---|---|
| Hamilton Island Airport | Australia | 0.0 mm (0.00 in) | 97.5 mm (3.8 in) | 0% | 26 |
| Gosnells City | Australia | 0.0 mm (0.00 in) | 87.4 mm (3.4 in) | 0% | 25 |
| Whiskeytown Rsvr | United States | 0.0 mm (0.00 in) | 71.8 mm (2.8 in) | 0% | 28 |
| Fairymead Sugar Mill | Australia | 0.0 mm (0.00 in) | 57.9 mm (2.3 in) | 0% | 27 |
| Lynton | Australia | 0.0 mm (0.00 in) | 48.7 mm (1.9 in) | 0% | 28 |
| North Shields (Port Lincoln Ae | Australia | 0.0 mm (0.00 in) | 41.3 mm (1.6 in) | 0% | 28 |
| Ornskoldsvik | Sweden | 0.0 mm (0.00 in) | 37.8 mm (1.5 in) | 0% | 30 |
| Ponciano Arriaga Intl | Mexico | 0.0 mm (0.00 in) | 36.6 mm (1.4 in) | 0% | 25 |
| Mundoora (Barunga North) | Australia | 0.0 mm (0.00 in) | 36.3 mm (1.4 in) | 0% | 30 |
| Pope Ridge | United States | 0.0 mm (0.00 in) | 36.2 mm (1.4 in) | 0% | 30 |
Weather Records
21,788 set or tied in May 202421,788 weather records were set or tied in May 2024, including 12,014 record highs and 3,951 record lows of maximum and minimum temperature, and 106 all-time records.
| Record high minimum temperature | |
|---|---|
| Record daily precipitation | |
| Record high maximum temperature | |
| Record low minimum temperature | |
| Record low maximum temperature | |
| Record daily snowfall | |
| Record snow depth |
| Daily | |
|---|---|
| Monthly | |
| All-time |
May Against the Ten Years Before
| Year | Record highs, percent of highs and lows |
|---|---|
| 2014 | 66.5% |
| 2015 | 63.6% |
| 2016 | 70.5% |
| 2017 | 60.4% |
| 2018 | 90.5% |
| 2019 | 46.3% |
| 2020 | 61.1% |
| 2021 | 52.3% |
| 2022 | 63.2% |
| 2023 | 68.8% |
| 2024 | 74.9% |
In May 2024, 75% of the daily temperature records were record highs (3.0 to 1 highs to lows), against an average of 64% for May in 2014 to 2023.
The Top 10 Records of May 2024
| Date | Station | Country | Record | Value | Significance |
|---|---|---|---|---|---|
| 2024-05-22 | Newton Rigg | United Kingdom | All-time precipitation | 81.5 mm (3.2 in) | 98 of 100 (Exceptional) |
| 2024-05-09 | Ust-Maja | Russia | Monthly precipitation | 61.0 mm (2.4 in) | 90 of 100 (Exceptional) |
| 2024-05-08 | Goldbutte 7 N | United States | All-time precipitation | 102.9 mm (4.1 in) | 86 of 100 (Exceptional) |
| 2024-05-21 | Fremont | United States | Monthly precipitation | 160.5 mm (6.3 in) | 83 of 100 (Exceptional) |
| 2024-05-31 | Augsburg | Germany | All-time precipitation | 98.2 mm (3.9 in) | 83 of 100 (Exceptional) |
| 2024-05-09 | Lebanon 7 N | United States | All-time precipitation | 179.6 mm (7.1 in) | 81 of 100 (Exceptional) |
| 2024-05-31 | Llano | United States | Monthly precipitation | 199.9 mm (7.9 in) | 81 of 100 (Exceptional) |
| 2024-05-02 | Roermond | Netherlands | Daily precipitation | 36.6 mm (1.4 in) | 80 of 100 (Exceptional) |
| 2024-05-03 | Allerton | United States | Daily precipitation | 92.2 mm (3.6 in) | 80 of 100 (Exceptional) |
| 2024-05-06 | Monticello | United States | Daily precipitation | 91.4 mm (3.6 in) | 80 of 100 (Exceptional) |
Countries With the Most Records
| Country | Records | Highs | Lows |
|---|---|---|---|
| United States | 9,539 | 4,025 | 2,658 |
| Australia | 1,616 | 596 | 212 |
| Germany | 884 | 395 | 1 |
| Russia | 818 | 333 | 331 |
| Netherlands | 715 | 107 | 0 |
| Finland | 709 | 609 | 73 |
| Sweden | 696 | 630 | 14 |
| Norway | 686 | 632 | 4 |
| China | 618 | 494 | 33 |
| Mexico | 396 | 388 | 1 |
| India | 364 | 274 | 40 |
| United Kingdom | 345 | 275 | 9 |
| Indonesia | 333 | 322 | 11 |
| Japan | 296 | 146 | 28 |
| Thailand | 273 | 235 | 6 |
Events and Storms
5 named storms had a best track position in May 2024; 3 peaked at 64 kt (119 km/h, 74 mph) or more and 0 at 96 kt (178 km/h, 110 mph) or more over their lifetime.
| Storm | Basin | Lifetime peak wind | Category at peak |
|---|---|---|---|
| Maliksi | Western North Pacific | 35 kt (65 km/h, 40 mph) | Tropical storm |
| Remal | North Indian | 60 kt (111 km/h, 69 mph) | Tropical storm |
| Ewiniar | Western North Pacific | 90 kt (167 km/h, 104 mph) | Category 2 |
| Ialy | South-West Indian | 65 kt (120 km/h, 75 mph) | Category 1 |
| Hidaya | South-West Indian | 80 kt (148 km/h, 92 mph) | Category 1 |
May 2024 in Context
These values come from other sources and the site's own analysis pages. They are context for May 2024; this page does not say that any of them caused the temperatures or records above.
How These Numbers Are Made
Each station's mean daily maximum and minimum temperature for May 2024 is compared with its own mean for May in 1991 to 2020, from months with at least 20 days of both. A station needs 20 such years for a normal. The mean is the average of the two differences. A station month more than 15 C (27 F) from its normal in either element is treated as a data error and left out.
For the world and each continent, stations are averaged within 5 degree grid cells and the cells are averaged weighted by the cosine of their latitude, so dense networks do not outweigh sparse ones. A continent uses the stations of its own countries. A year gets a value and a rank only when its cells hold at least 50% of the weight of all the cells that have ever had data for May, the rule of the climate pages. This is a station based view: places without stations are not covered, and it is not a gridded temperature analysis.
Records are the site's public ledger: one record per observation, set or tied, at its broadest timescale. The ten year comparison uses daily temperature records only, ties excluded. The numbers and sentences on this page are generated by code from the station data; none of them is typed in by hand.
Download the Data
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Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Source: International Best Track Archive for Climate Stewardship (IBTrACS) v04r01, NOAA National Centers for Environmental Information, doi:10.25921/82ty-9e16. Some agency values come from third parties such as JMA, IMD and BoM. (NOAA NCEI terms (citation requested)) Source: NOAA Climate Prediction Center, Oceanic Nino Index (ONI) and Relative Oceanic Nino Index (RONI). Episodes and strength classes are computed by World Extreme Weather Monitor and are not NOAA products. (US Government work, public domain (NWS disclaimer)) Source: Fetterer, F., Knowles, K., Meier, W. N., Savoie, M., Windnagel, A. K. and Stafford, T. (2025). Sea Ice Index, Version 4 (G02135). Boulder, Colorado USA. National Snow and Ice Data Center. doi:10.7265/a98x-0f50. Yearly extremes, ranks, trends and the climatology are computed by World Extreme Weather Monitor from the daily extent files and are not NSIDC products. (NSIDC data use and citation policy (public domain government funded data, citation required)) Source: NOAA Global Monitoring Laboratory, Earth System Research Laboratories (gml.noaa.gov/ccgg/trends). Mauna Loa CO2 data are from NOAA and Scripps (before 1974 the monthly values come from the Scripps Institution of Oceanography). The global means of CO2, methane and nitrous oxide are from the NOAA GML cooperative air sampling network (methane and nitrous oxide: Lan, Thoning and Dlugokencky, doi:10.15138/P8XG-AA10). (US Government open data (NOAA GML, citation requested)) Data as of 2026-11-09. Temperatures against normal, ranks and records are computed by this site from station data and are not official.