In the atmosphere, 500-millibar height pressure anomalies correlate well with temperatures at the Earth's surface. The average position of the upper-level ridges of high pressure and troughs of low pressure—depicted by positive and negative 500-millibar height anomalies on the July 2021 map, is generally reflected by areas of positive and negative temperature anomalies at the surface, respectively.
Monthly Temperature: July 2021
Temperature anomalies and percentiles are shown on the gridded maps below. The anomaly map on the left is a product of a merged land surface temperature (Global Historical Climatology Network, GHCN) and sea surface temperature (ERSST version 5) anomaly analysis. Temperature anomalies for land and ocean are analyzed separately and then merged to form the global analysis. For more information, please visit NCEI's Global Surface Temperature Anomalies page. The percentile map on the right provides additional information by placing the temperature anomaly observed for a specific place and time period into historical perspective, showing how the most current month, season or year compares with the past.
The month of July was characterized by warmer-than-average temperatures across much of the globe. Much-warmer-than-average temperatures were observed across parts of North America, northern and eastern Europe, northern Africa, the Middle East, southern Asia, northern and southern parts of Argentina, as well as the Atlantic, Pacific, and Indian oceans. Record-warm July temperatures were observed across parts of western North America, the Atlantic Ocean, Europe, northern Africa, southern Asia, and small areas across the southern Pacific and Indian oceans. The record-warm July temperatures encompassed 5.06% of the world's surface — the seventh highest July percentage for record-warm July temperatures since records began in 1951. Meanwhile, cooler-than-average conditions were present across parts of the south-central and southeastern contiguous U.S., northeastern Canada, southern Africa, northern Russia, and the southeastern Pacific Ocean. However, no land or ocean areas had a record-cold July temperature.
A positive Arctic Oscillation (AO) was present in July. The July 2021 AO value of 0.625 was the fifth highest for July since 1950. The four highest AO July values occurred in 1964 (0.734), 1989 (0.866), 1996 (0.715), and 2017 (0.634). The ridges that brought high temperature anomalies over northern Europe and northeastern Asia were associated with the positive AO.
As a whole, the July 2021 global surface temperature was the highest for July since global records began in 1880 at 0.93°C (1.67°F) above the 20th-century average of 15.8°C (60.4°F). This value surpassed the previous record set in 2016 (and subsequently matched in 2019 and 2020) by only 0.01°C (0.02°F). Because July is the warmest month of the year from a climatological perspective, July 2021 was more likely than not the warmest month on record for the globe since 1880. Nine of the 10 warmest Julys have occurred since 2010, with the last seven Julys (2015-2021) being the seven warmest Julys on record. July 1998 is the only July from the 20th century to be among the 10 warmest Julys on record. July 2021 marked the 45th consecutive July and the 439th consecutive month with temperatures, at least nominally, above the 20th-century average.
The global land-only surface temperature for July 2021 was 1.40°C (2.52°F) above the 20th-century average — the highest July land-only surface temperature on record, surpassing the previous record set in 2017, and again in 2020, by 0.17°C (0.31°F). The warmth across the global land surfaces was mainly driven by higher than normal temperatures across much of the Northern Hemisphere land, which also had its highest July temperature at 1.54°C (2.77°F), exceeding the now second warmest July set in 2012 by 0.19°C (0.34°F). Overall, the Northern Hemisphere land and ocean surface had its second warmest July on record at +1.14°C (+2.05°F). This was only 0.06°C (0.11°F) shy of tying the record warm July of 2020.
Asia's July 2021 surface temperature was 1.61°C (2.90°F) above average — the highest July temperature departure since 1910. This value was 0.23°C (0.41°F) higher than the previous record set in July 2010. Nine of Asia's 10 warmest Julys have occurred since 2005. According to the Kingdom of Bahrain Meteorological Directorate Climate Section, Bahrain had its second warmest July on record, with a mean temperature that was 1.4°C (2.5°F) above average. This was 0.4°C (0.7°F) shy of tying the record warm July set in 2017, and again in 2020. Hong Kong had its fourth warmest July on record with a temperature that was 0.9°C (1.6°F) above average.
Europe had its second warmest July (tied with 2010), with a temperature departure of +2.37°C (+4.27°F). This was only 0.10°C (0.18°F) shy of tying the warmest July set in 2018. Across Europe, the United Kingdom's July 2021 temperature of 16.6°C (61.9°F) was 1.5°C (2.7°F) above average and tied as the fifth highest July temperature since national records began in 1884. According to the Copernicus Climate Change Service, Helsinki, Finland had its second warmest July on record, behind 2010. During the end of the month, a severe heat wave affected parts of southern Europe, with several locations recording temperatures above 40.0°C (104.0°F). Minimum temperatures were also above average. According to preliminary reports, the Kalymnos Island, Greece, reported a minimum temperature of 34.3°C (93.7°F) on July 31—if verified, it would be the highest minimum July temperature on record in Europe and the second highest for all months.
Meanwhile, North America, South America, Africa, and Oceania had a top 10 warm July.
Australia's July 2021 mean temperature was 1.77°C (3.19°F) above average, which is the fourth warmest July in the nation's 112-year record. Regionally, South Australia, Western Australia, and the Northern Territory had a top three warm July on record. Queensland had it seventh warmest July on record.
New Zealand's July 2021 temperature was 1.1°C (2.0°F) above average and tied as the sixth warmest July on record.
(out of 142 years)
|Land||+1.40 ± 0.27||+2.52 ± 0.49||Warmest||1st||2021||+1.40||+2.52|
|Ocean||+0.75 ± 0.14||+1.35 ± 0.25||Warmest||6th||2019||+0.83||+1.49|
|Land and Ocean||+0.93 ± 0.19||+1.67 ± 0.34||Warmest||1st||2021||+0.93||+1.67|
|Land||+1.54 ± 0.21||+2.77 ± 0.38||Warmest||1st||2021||+1.54||+2.77|
|Ocean||+0.90 ± 0.13||+1.62 ± 0.23||Warmest||6th||2020||+1.13||+2.03|
|Land and Ocean||+1.14 ± 0.21||+2.05 ± 0.38||Warmest||2nd||2020||+1.20||+2.16|
|Land||+1.05 ± 0.13||+1.89 ± 0.23||Warmest||5th||2017||+1.34||+2.41|
|Ocean||+0.63 ± 0.15||+1.13 ± 0.27||Warmest||4th||2016||+0.70||+1.26|
|Land and Ocean||+0.70 ± 0.15||+1.26 ± 0.27||Warmest||5th||2016, 2019||+0.75||+1.35|
The most current data can be accessed via the Global Surface Temperature Anomalies page.
Year-to-date Temperature: January–July 2021
The January–July 2021 global surface temperature of 0.81°C (1.46°F) above average tied with 2018 as the sixth highest such period in the 142-year record. Looking ahead, the year 2021 is very likely to rank among the ten warmest years on record, according to a statistical analysis done by NCEI scientists.
During January–July 2021, warmer-than-average conditions were observed across much of the globe, with record-warm January–July temperatures across parts of the Pacific Ocean, Africa, and southern Asia. Near- to cooler-than-average temperatures were present across parts of the eastern Pacific Ocean, the south-central and southeastern contiguous U.S., the North Atlantic Ocean, central Russia, and the southern oceans. However, no land or ocean areas had a record-cold January–July temperature.
Regionally, Africa had its third warmest January–July period since continental records began in 1910. Only January–July of 2010 and 2016 were warmer. North America, South America, and Asia had a top 10 warm January–July on record. Meanwhile, Oceania had its coolest year-to-date since 2012.
(out of 142 years)
|Land||+1.32 ± 0.18||+2.38 ± 0.32||Warmest||6th||2016||+1.76||+3.17|
|Ocean||+0.62 ± 0.17||+1.12 ± 0.31||Warmest||7th||2016||+0.84||+1.51|
|Land and Ocean||+0.81 ± 0.18||+1.46 ± 0.32||Warmest||6th||2016||+1.09||+1.96|
|Land||+1.54 ± 0.20||+2.77 ± 0.36||Warmest||4th||2016||+1.98||+3.56|
|Ocean||+0.76 ± 0.17||+1.37 ± 0.31||Warmest||6th||2020||+0.98||+1.76|
|Land and Ocean||+1.06 ± 0.18||+1.91 ± 0.32||Warmest||6th||2016, 2020||+1.35||+2.43|
|Land||+0.75 ± 0.14||+1.35 ± 0.25||Warmest||16th||2019||+1.28||+2.30|
|Ocean||+0.53 ± 0.18||+0.95 ± 0.32||Warmest||11th||2016||+0.76||+1.37|
|Land and Ocean||+0.56 ± 0.17||+1.01 ± 0.31||Warmest||12th||2016||+0.83||+1.49|
The maps shown below represent anomalies (left, using a base period of 1961–1990) and percent of normal (right, using the same base period) based on the GHCN dataset of land surface stations. As is typical, precipitation anomalies during July 2021 varied significantly around the world.
Significantly below-average precipitation occurred across northwestern contiguous U.S. to the Canadian Prairies, much of Argentina, northeastern and southern Europe, and parts of Australia and eastern and southern Asia. Significantly above-normal precipitation occurred in southern and northeastern parts of the United States, northern parts of South America, and parts of Europe, eastern Asia, and southern Australia.
Several locations across southern Europe had drier-than-average conditions during the month. The dry conditions combined with very warm temperatures helped with the development and spread of dangerous wildfires in the region by the end of the month. According to media reports, destructive wildfires affected parts of southern and southwestern Turkey, forcing residents to evacuate. Devastating wildfires also affected parts of northeastern Spain. For the month as a whole, Spain had below-average July precipitation, receiving only 57% of normal July precipitation.
Parts of western Europe had torrential rains that caused deadly floods during July 13–15, with some locations receiving at least twice their normal monthly precipitation in only three days. According to preliminary reports, over 140 fatalities across western Germany and Belgium were attributed to the devastating floods. The high flood levels were also responsible for damaging homes in the affected regions.
Much of northern Austria had wetter-than-average conditions during July 2021, with several locations receiving twice their normal July precipitation. Heavy rain fell across parts of northern Austria during July 17–18, setting several new precipitation records. Of note, Kufstein (northwestern Austria) set a new 48-hour precipitation record when a total of 163 mm (6.4 inches) fell during that time. The Wien-Hohe Warte station set a new 3-hour precipitation record when it received 80 mm (3.1 inches) of rain during that period of time. Meanwhile, southern Austria had below-average July precipitation, with deficits ranging between 20%–50% below average. Overall, Austria's July 2021 precipitation total was 25% above average and the wettest July since 2016.
According to the World Meteorological Organization, Zhengzhou, in the Henan province, China, received 382 mm (15.0 inches) — a little over half of its average annual precipitation of 641 mm (25.2 inches) — in only six hours on July 20 and more than 640 mm during a short period of four days. The copious rain prompted dangerous floods and over 20 fatalities were attributed to the heavy rain.
Drier-than-average conditions engulfed much of Argentina during the month. According to Argentina's Servicio Nacional Meteorológico, about 75% of the Paraná basin was in moderate to exception drought, which encompasses about 70 million ha. Also, about 75% of the Paraguay river basin was also suffering some type of drought as of August 3. Precipitation total for southern Argentina was 200 mm below the 1981–2010 average during the three-month period of May through July. Lack of snow across Patagonia was also reported, with some locations reporting their lowest values since 2000.
Australia, as a whole, had near-average precipitation during July 2021. Regionally, the Northern Territory had the largest rainfall precipitation deficit at 88% below average.
Global Precipitation Climatology Project (GPCP)
The following analysis is based upon the Global Precipitation Climatology Project (GPCP) Interim Climate Data Record. It is provided courtesy of the GPCP Principal Investigator team at the University of Maryland.
The Global Precipitation Climatology Project (GPCP) monthly data set is a long-term (1979-present) analysis (Adler et al., 2018) using a combination of satellite and gauge information. An interim GPCP analysis completed within ~10 days of the end of the month allows its use in climate monitoring.
The global precipitation map for July 2021 (Fig. 1, top panel) shows the large area of intense rainfall associated with the Asian monsoon stretching across the Indian sub-continent, the Himalayas, China and Japan, and the Indian and Western Pacific Oceans. It is certainly the dominant feature of this month. The other tropical rain features, including the ITCZs in the Pacific and Atlantic and Africa and South America have also moved near their northernmost positions. The dry zones in the sub-tropics have also shifted in the same direction. This seasonal shift brings the dry season to much of the land areas south of the Equator.
The anomaly maps (magnitude and percentage in the middle and bottom panels of Fig. 1) also have some strong features associated with the Asian monsoon, with positive anomalies dominating over India and China and surrounding waters, indicating a strong start to this year's monsoon in this region. The strongest and largest positive anomaly in this area is in the western Pacific and extending into eastern China. This feature on the monthly scale is the result of a number of rain systems, some frontal related in the early part of the month and a series of mostly weak tropical cyclones over the water. However, slow-moving Typhoon In-fa late in the month organized east of Taiwan and moved slowly onto the China coast and progressed inland with copious rainfall. This event was just the latest heavy rainfall event in eastern China for the month that resulted in very serious flooding in various locations there.
In addition to the flooding in China, floods and landslides resulted in significant loss of life across the globe this month with over 900 deaths in over 100 flood events across 20 countries (FloodList: https://floodlist.com/asia/world-floods-july-2021). The worst loss of life occurred in western Germany and Belgium with over 100 dead, with the associated monthly rainfall evident in the anomaly maps, although much weaker and with a smaller scale than the features in China. Heavy rain also contributed to floods in India (especially just east of the Ghats Mountains in central India), in the foothills of Nepal and in Sudan and Ethiopia and also a devastating landslide in Japan associated with 250 mm of rain. Some of these events, e.g., the rain feature associated with the Japan landslide, are of such small scale that they are not obvious in the anomaly maps at coarse scale (monthly, 2.5° latitude/longitude of the analysis).
Although not of the same large scale as the Asian monsoon, North America has its own summer monsoon with its main moisture source the eastern-most Pacific Ocean along the western coast of Mexico and rainfall in July–August spreading northward through the Mexican mountains into the southwest U.S. For this July, the rainfall, especially in Arizona and New Mexico (and even southwest Colorado) has helped alleviate the on-going drought there to some degree. This effect shows up in the anomaly maps as the positive feature over the area and as an extension of the positive anomaly over the southeast U.S. This monsoon rainfall also greatly reduced the wildfire occurrences in the region so far this season, but also led to some flash flooding. However, further to the west and northwest, over California and northward in Canada, negative rainfall anomalies predominate and the wildfires there have been devastating and produced prodigious amounts smoke that have affected wide swaths of the U.S.
Most of Canada was drier than normal and over northern Eurasia there was an alternating pattern of positive and negative anomalies and where there was a relative lack of precipitation, wildfires were evident, for example in Siberia. Drought and continued lack of rain in southeast Brazil. Even Hawaii is suffering from drought and its negative anomaly for July has not helped the situation. Connected somewhat to the current situation in Hawaii, but also to longer-time-scale changes, i.e., global warming, the ITCZ in the eastern half of the Pacific and the surrounding subtropics to the north and south show, for this July, a dominating pattern of the core of the ITCZ having a positive anomaly and areas to the north and south having negative anomalies. This is a good example of wet areas getting wetter and dry areas getting drier, showing up here in one month, but also showing up in trends over decades. Although disconnected from more complicated land areas this area may point to this trend toward extremes and indicates the importance of monitoring ocean areas and globe as a whole.
Background discussion of long-term means, variations and trends of global precipitation can be found in Adler et al. (2017).
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