Assessing the Global Climate in April 2018

The global land and ocean temperature departure from average for April 2018 was the third highest for April in the NOAA global temperature dataset record, which dates back to 1880. The year-to-date (January-April) global temperature was the fifth warmest such period in the 139-year record.

This monthly summary, developed by scientists at NOAA's National Centers for Environmental Information, is part of the suite of climate services NOAA provides to government, business, academia and the public to support informed decision-making.

April 2018 Temperature

• The April temperature across global land and ocean surfaces was 1.49°F above the 20th century average of 56.7°F and the third highest for April in the 1880-2018 record. Only April 2016 (+1.94°F) and 2017 (+1.60°F) were warmer. Nine of the 10 warmest Aprils have occurred since 2005. April 2018 also marks the 42nd consecutive April and the 400th consecutive month with temperatures, at least nominally, above the 20th century average.

• The April globally averaged land surface temperature was 2.36°F above the 20th century average of 46.5°F. This was the ninth highest April land global temperature in the 139-year record.

  • Warmer-than-average conditions engulfed much of Europe during April 2018. Several central European countries had a record or near-record warm April. Averaged as a whole, Europe had its warmest April temperature since 1910.

  • Argentina had its highest April temperature since 1961, while Australia had its second highest April temperature since 1910.

  • Cooler-than-average conditions were present across much of North America, tying with 1918 as the 15th coldest April since continental records began in 1910.

• The April globally averaged sea surface temperature was 1.17°F above the 20th century monthly average of 60.9°F – the fourth highest April global ocean temperature since records began in 1880, trailing behind 2016 (+1.42°F), 2017 (+1.30°F) and 2015 (+1.19°F).

April 2018 Sea Ice and Snow Cover

• The April average Arctic sea ice extent was the second smallest in the 39-year record at 378,000 square miles (6.8 percent) below the 1981-2010 average, according to analysis by the National Snow and Ice Data Center using data from NOAA and NASA. Only the April Arctic sea ice extent in 2016 was smaller. Record-low sea ice was observed in the Bering Sea with below-average sea ice in the Barents Sea.

• Antarctic sea ice extent during April was 320,000 square miles (12.3 percent) below the 1981-2010 average, the fifth smallest April extent on record. Antarctic sea ice rapidly expanded during the first half of April, but slowed later in the month.

• According to data from NOAA and analyzed by the Rutgers Global Snow Lab, the Northern Hemisphere snow cover extent during April was 710,000 square miles above the 1981-2010 average. This ranked as the 10th largest April extent in the 52-year period of record and was the largest since 2013. The North American April snow cover extent was the fourth largest on record and largest since 2013, while the Eurasian snow cover extent was near average.

Year-to-Date (January–April 2018)

• The year-to-date temperature across global land and ocean surfaces was 1.37°F above the 20th century average of 54.8°F. This was the fifth highest for January-April in the 139-year record. The 2018 year-to-date value was 0.70°F lower than the record high set in 2016 and was the coolest such period since 2014. The years 2015-2017 rank among the three warmest January-April periods on record.

• The year-to-date globally averaged land surface temperature was 2.21°F above the 20th century average of 40.5°F and was the sixth highest for January-April in the record. This was also the smallest January-April global land temperature departure from average since 2014.

• The year-to-date globally averaged sea surface temperature was 1.06°F above the 20th century average of 60.7°F – also the fifth highest for January-April in the 1880-2018 record. This value was also the smallest January-April global ocean temperature departure since 2014.

For a more complete summary of climate conditions and events, see our April 2018 Global Climate Report.