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.v4) anomaly analysis as described in Huang et al. (2016). 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.
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 April 2017 map—is generally reflected by areas of positive and negative temperature anomalies at the surface, respectively.
The combined global average temperature over the land and ocean surfaces for April 2017 was 0.90°C (1.62°F) above the 20th century average of 13.7°C (56.7°F)—the second highest April temperature since global records began in 1880, trailing 2016 by 0.17°C (0.31°F) and ahead of 2010 by 0.0.7°C (0.13°F). April 2017 also marks the 388th consecutive month that the globally-averaged temperature across the world's land and ocean surfaces was nominally above the 20th century average. December 1984 was the last time a monthly temperature was below average at -0.09°C (-0.16°F). Overall, April 2017 tied with March 2015, August 2016, and January 2017 as the 12th highest monthly global land and ocean temperature departure from average on record (1,648 monthly records).
Warmer-than-average temperatures during the month were observed across much of the world's land surfaces, with the most notable warm temperature departures from average across the Northern Hemisphere higher latitudes, specifically across much of central and eastern Asia, Alaska and the eastern half of the contiguous U.S., where temperatures were 3.0°C (5.4°F) above average or higher. Several locations across Russia's Far East had record warm temperatures during April 2017. Near- to cooler-than-average temperatures were observed across the northwestern contiguous U.S., much of Canada, central South America, Scandinavia, central and eastern Europe, western Russia, central and southeastern Asia, and much of Australia. The most notable cool anomalies were observed across northern Canada, where temperatures were 2.0°–3.0°C (3.6°–5.4°F) below average or lower. No land areas had a record cold April. According to NCEI's Regional Analysis, North America, Africa, and Asia had a top 10 warm April, while Europe had its coolest April since 2003. The average global temperatures across land surfaces was 1.37°C (2.47°F) above the 20th century average of 8.1°C (46.5°F)—tying with 2000 and 2010 as the fourth highest April temperature in the 138-year record, behind 2016 (1.87°C / 3.37°F), 2007 (1.52°C / 2.74°F), and 2012 (1.50°C / 2.70°F).
Select national information is highlighted below. Please note that different countries report anomalies with respect to different base periods. The information provided here is based directly upon these data:
- North America had cooler-than-average temperatures across the northwestern contiguous U.S. and much of Canada, while Alaska, the rest of the contiguous U.S. and Mexico had warmer- to much-warmer-than-average conditions during April 2017. Overall, the April 2017 average temperature for North America was +1.22°C (+2.20°F), tying with 1941 and 1977 as the tenth highest April temperature since continental averages began in 1910.
- According to NCEI's National Climate Report, the contiguous U.S. had warmer- to much-warmer-than-average conditions across much of the eastern half of the nation, resulting in the warmest April since 2012 and the 11th warmest since national records began in 1895.
- Alaska and Mexico also had warmer-than-average conditions during the month. Alaska's April 2017 temperature was 3.7°C (6.6°F) above average and the sixth highest April temperature in the state's 93-year record.
- In contrast, much of Canada experienced near- to cooler-than-average conditions, with temperatures -2.0°C (-3.6°F) below average or cooler.
- Temperatures varied across Europe during April 2017, with cooler-than-average conditions across much of Europe, with the exception of western Europe. Overall, April 2017 was the coolest April since 2003.
- April 2017 average temperature for Spain was 14.9°C (58.8°F) or 1.9°C (3.4°F) above the 1981–2010 average. This was the fourth highest April temperature since 1965.
- The United Kingdom's mean temperature was 8.0°C (46.4°F) and 0.6°C (1.1°F) above the 1981–2010 average. Mean maximum and minimum temperatures were above average, ranging 0.5°C (0.9°F) to 1.5°C (2.7°F) above average.
- Cooler-than-average conditions dominated the western half of Europe. Several countries reported that April 2017 was cooler than March 2017. Austria's national temperature for April was 0.2°C (0.4°F) below the 1981–2010 average—the coolest April in nine years.
- Much of Asia was engulfed by warmer- to much-warmer-than-average temperatures during April 2017, with several locations across Russia's Far East experiencing record warmth. Averaged as a whole, Asia had its eighth highest April temperature in the 108-year record.
- Bahrain's April 2017 mean temperature was 27.6°C (81.7°F), which is 2.6°C (4.7°F) above average. This was the highest mean temperature for April since national records began in 1902. The previous record was 27.4°C (81.3°F) set in 2000 and then again in 2014. The nation's mean maximum temperature of 32.0°C (89.6°F) was the third highest for April since 1946, behind 2000 (33.1°C / 91.6°F) and 2001 (32.5°C / 90.5°F), and the mean minimum temperature of 24.1°C (75.4°F) tied with 2010 as the highest for April since 1946.
- Drier-than-average conditions were present across much of Spain during April 2017, receiving only 40% of average precipitation (65 mm). This was the driest April in the 21st century.
- France was also very dry during April 2017. Averaged as a whole, France's precipitation deficit was greater than 50%. This resulted in France having one of the ten driest April since 1959, comparable with 2007 and 2010.
- Much of the United Kingdom had below-average precipitation. April 2017 precipitation was 48% of average—the tenth driest April since national records began in 1910.
- Peterson, T.C. and R.S. Vose, 1997: An Overview of the Global Historical Climatology Network Database. Bull. Amer. Meteorol. Soc., 78, 2837-2849.
- Huang, B., V.F. Banzon, E. Freeman, J. Lawrimore, W. Liu, T.C. Peterson, T.M. Smith, P.W. Thorne, S.D. Woodruff, and H-M. Zhang, 2016: Extended Reconstructed Sea Surface Temperature Version 4 (ERSST.v4). Part I: Upgrades and Intercomparisons. J. Climate, 28, 911-930.
Much of the world's oceans also had warmer- to much-warmer-than-average conditions during April 2017, with several locations across the western, central, and southeastern Pacific Ocean, Indian Ocean, and Atlantic Ocean experiencing record warm temperatures. No ocean areas had record cold April temperatures. Overall, the global sea surface temperature for April 2017 was 0.73°C (1.31°F) above the 20th century average of 16.0°C (60.9°F) and the second highest April temperature since records began in 1880. This value is 0.05°C (0.09°F) less than the record year set in 2016, but 0.07°C (0.13°F) higher than 2015.
ENSO-neutral conditions prevailed across the equatorial Pacific Ocean during April 2017. According to NOAA's Climate Prediction Center, ENSO-neutral and El Niño are equally favored during the Northern Hemisphere summer and fall (Southern Hemisphere winter and spring) 2017. This forecast focuses on the ocean surface temperatures between 5°N and 5°S latitude and 170°W to 120°W longitude, called the Niño 3.4 region.
(out of 138 years)
|Land||+1.37 ± 0.11||+2.47 ± 0.20||Warmest||4th||2016||+1.87||+3.37|
|Ties: 2000, 2010|
|Ocean||+0.73 ± 0.14||+1.31 ± 0.25||Warmest||2nd||2016||+0.78||+1.40|
|Land and Ocean||+0.90 ± 0.13||+1.62 ± 0.23||Warmest||2nd||2016||+1.07||+1.93|
|Land||+1.58 ± 0.15||+2.84 ± 0.27||Warmest||5th||2016||+2.08||+3.74|
|Ocean||+0.76 ± 0.13||+1.37 ± 0.23||Warmest||2nd||2016||+0.82||+1.48|
|Land and Ocean||+1.07 ± 0.13||+1.93 ± 0.23||Warmest||2nd||2016||+1.30||+2.34|
|Land||+0.80 ± 0.11||+1.44 ± 0.20||Warmest||14th||2016||+1.32||+2.38|
|Ocean||+0.72 ± 0.15||+1.30 ± 0.27||Warmest||2nd||2016||+0.77||+1.39|
|Land and Ocean||+0.73 ± 0.14||+1.31 ± 0.25||Warmest||2nd||2016||+0.85||+1.53|
The most current data can be accessed via the Global Surface Temperature Anomalies page.
The global land and ocean surface temperature during January–April 2017 was 0.95°C (1.71°F) above the 20th century average of 12.6°C (54.8°F). This was the second highest such period since records began in 1880, behind 2016 by 0.19°C (0.34°F) and ahead of 2015 by 0.10°C (0.18°F).
The year-to-date global land surface temperature was also the second highest on record at 1.64°C (2.95°F) above average. This value is 0.39°C (0.70°F) less than the record January–April 2016, but 0.18°C (0.32°F) higher than the now third warmest such period set in 2015. The average global ocean surface temperature for the year-to-date was also second highest in the 138-year record at 0.70°C (1.26°F), behind 2016 by 0.11°C (0.20°F) and 0.08°C (0.14°F) higher than 2015. As illustrated in the temperature departure from average and percentiles maps, much of the world's land and ocean surface experienced warmer- to much-warmer-than-average April temperatures, with several locations across the southern and southeastern contiguous U.S., Mexico, eastern Russia, eastern Australia, western, central, and eastern Pacific Ocean, western Indian Ocean, and across the southern Atlantic Ocean experiencing record warmth. No land or ocean areas had record cold temperatures during April 2017. According to NCEI's Regional Analysis, five of six continents had a top nine warm April, with Europe having its coolest April since 2013 and tying with 1975 as the 14th warmest April on record.
(out of 138 years)
|Land||+1.64 ± 0.16||+2.95 ± 0.29||Warmest||2nd||2016||+2.03||+3.65|
|Ocean||+0.70 ± 0.16||+1.26 ± 0.29||Warmest||2nd||2016||+0.81||+1.46|
|Land and Ocean||+0.95 ± 0.16||+1.71 ± 0.29||Warmest||2nd||2016||+1.14||+2.05|
|Land||+1.90 ± 0.21||+3.42 ± 0.38||Warmest||2nd||2016||+2.30||+4.14|
|Ocean||+0.73 ± 0.15||+1.31 ± 0.27||Warmest||2nd||2016||+0.86||+1.55|
|Land and Ocean||+1.17 ± 0.17||+2.11 ± 0.31||Warmest||2nd||2016||+1.40||+2.52|
|Land||+0.97 ± 0.14||+1.75 ± 0.25||Warmest||6th||2016||+1.34||+2.41|
|Ocean||+0.68 ± 0.16||+1.22 ± 0.29||Warmest||2nd||2016||+0.79||+1.42|
|Land and Ocean||+0.73 ± 0.16||+1.31 ± 0.29||Warmest||2nd||2016||+0.87||+1.57|
The most current data can be accessed via the Global Surface Temperature Anomalies page.
The maps below represent precipitation percent of normal (left, using a base period of 1961–1990) and precipitation percentiles (right, using the period of record) based on the GHCN dataset of land surface stations. As is typical, precipitation anomalies during April 2017 varied significantly around the world. April 2017 precipitation was generally drier than normal across Alaska, the southwestern contiguous U.S., Mexico, northeastern Brazil, southwestern and northern Europe, Australia, and scattered across southern, central, and eastern Asia. Wetter-than-normal conditions were notable across the eastern half of the contiguous U.S., southern South America, eastern Europe, and across northern and southeastern Asia.
Select national information is highlighted below. (Please note that different countries report anomalies with respect to different base periods. The information provided here is based directly upon these data):