| Above: The deadliest weather-related disaster of June was in Bangladesh, where the arrival of the southwest monsoon brought torrential rains that brought devastating flooding and landslides in southeastern portions of the country on June 12 – 13, killing 155 people. An additional 15 people died in the neighboring Indian states of Mizoram and Assam, bringing the total death toll to 170. Portions of Bangladesh’s power grid were destroyed, leading to widespread power outages, and total economic damage was estimated in the tens of millions of dollars. In this image, we see Bangladeshi fire fighters and residents search for victims of a landslide in Bandarban on June 13, 2017. Image credit: STR/AFP/Getty Images. |
June 2017 was the planet's third warmest June since record keeping began in 1880, said NOAA's National Centers for Environmental Information (NCEI) on Monday. NASA rated June 2017 as the fourth warmest June on record. The only warmer Junes came in El Niño years: 1998, 2015 and 2016. Minor differences can occur between the NASA and NOAA rankings because of their different techniques for analyzing data-sparse regions such as the Arctic.
Global ocean temperatures last month were the third warmest on record for any June, according to NOAA, and global land temperatures were the fourth warmest on record. Global satellite-measured temperatures for the lowest 8 km of the atmosphere were the 12th warmest or 7th warmest for any June in the 39-year record, according to the University of Alabama Huntsville (UAH) and Remote Sensing Systems (RSS), respectively.
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| Figure 1. Departure of temperature from average for June 2017, the third warmest June for the globe since record keeping began in 1880. Record warmth was observed across parts of the northern and southern Atlantic Ocean, specifically near the U.S. eastern coast, the African west coast and the southern South America east coast, central Asia and scattered across parts of Africa, western Europe, the Middle East, Brazil, and western Indian Ocean. Five of six continents had a top ten warm June, with Africa experiencing its warmest June since continental records began in 1910. No land or ocean areas experienced record cold June temperatures. Image credit: National Centers for Environmental Information (NCEI). |
Second-warmest year on record thus far
Each of the first six months of 2017 have ranked among the top three warmest months on record, giving 2017 the second highest January–June period in the 138-year record: 0.91°C (1.64°F) above the 20th century average of 13.5°C (56.3°F). This is behind the record year of 2016 by 0.16°C (0.29°F), but beats third-place 2015 by 0.05°C (0.09°F). This near-record warmth is especially remarkable given the lack of an El Niño event this year. Global temperatures tend to be warmer during El Niño years, when the ocean releases more heat to the atmosphere.
Two billion-dollar weather disasters in June 2017
Two billion-dollar weather disasters hit the Earth last month, according to the June 2017 Catastrophe Report from insurance broker Aon Benfield: a $1.4 billion severe weather outbreak in the Midwestern U.S., and a $2.4 billion flood in the Yangtze River valley of China. By the end of June, Earth had registered twelve billion-dollar weather events for 2017, which is a typical number for this point in the year. The year that ended with the most billion-dollar weather disasters in records going back to 1990 was 2013, with 41, and that year had seventeen billion-dollar disasters by the end of June. Last year, there were already 21 billion-dollar weather disasters by the end of June (that year ended up with 31 such disasters). Here are this year’s billion-dollar weather disasters through the end of June:
Flooding, Peru, 1/1 – 4/1, $3.1 billion, 120 killed
Severe Weather, Rockies, Plains, U.S., 5/8 – 5/11, $2.5 billion, 0 killed
Flooding, China, 6/22 – 6/27, $2.4 billion, 31 killed
Severe Weather, Plains, Southeast, Midwest U.S., 3/26 – 3/28, $2.2 billion, 0 killed
Severe Weather, Midwest, Plains, Southeast U.S., 3/6 – 3/10, $2.1 billion, 0 killed
Severe Weather, Midwest, Plains, Southeast MS Valley U.S., 4/28 – 5/01, $2.0 billion, 20 killed
Tropical Cyclone Debbie, 3/27 – 4/5, $2.0 billion, 14 killed
Drought, Somalia, Ethiopia, Kenya, 1/1 – 3/31, $1.9 billion, hundreds killed
Severe Weather, South U.S., 2/27 - 3/2, $1.9 billion, 4 killed
Severe Weather, Midwest U.S., 6/11, $1.4 billion, 0 killed
Severe Weather, South U.S., 1/18 - 1/23, $1.3 billion, 21 killed
Winter Weather, Plains, Southeast, Midwest, Northeast U.S., 3/13 - 3/15, $1.0 billion, 11 killed
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| June Billion-Dollar Disaster 1. A line of severe thunderstorms known as a bow echo raced across eastern South Dakota, southern Minnesota and into Wisconsin and the Upper Peninsula of Michigan with wind gusts of 60-80 mph and large hail on June 11, leaving multiple people injured and knocking out power to over 90,000 customers. The Minneapolis – St. Paul metro region had substantial wind and hail damage to homes, businesses, and vehicles. Total economic losses were expected to approach $1.4 billion. Above, we see Peonies before and after the June 11, 2017 hailstorm, north of St. Paul, Minnesota. Image credit: Minnesota State Climatology Office. |
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| June Billion-Dollar Disaster 2. Flooding in nine southern Chinese provinces from June 22-27 – caused by seasonal Mei-yu rains – claimed at least 31 lives and damaged or destroyed more than 130,000 homes. A burst of convective activity on the rainband prompted torrential downpours that affected a vast swath of the Yangtze River Basin from June 22- 25. Across the provinces of Sichuan, Yunnan, Chongqing, Guizhou, Hubei, Hunan, Anhui, Jiangxi, and Zhejiang economic losses reached CNY15.8 billion (USD2.35 billion). Additional flooding in the south from a separate pulse of the seasonal rains led to another CNY400 million (USD60 million) in damage. Above: a flooded street in Changsha, Hunan province on July 2, 2017. Days of torrential rain in Hunan province raised the water level of the Xiangjiang river to exceed its record flood level. Image credit: STR/AFP/Getty Images. |
No El Niño or La Niña conditions expected into winter
In its July 13 monthly advisory, NOAA’s Climate Prediction Center (CPC) stated that neither El Niño nor La Niña conditions were present in the Eastern Pacific (ENSO-neutral conditions existed), and these neutral conditions were expected to persist into the Northern Hemisphere winter (50 – 55% chance.) Sea surface temperatures (SSTs) in the benchmark Niño 3.4 region (in the equatorial Pacific) were about 0.5°C above average over the past week; SSTs of 0.5°C or more above average in this region are required to be classified as weak El Niño conditions, with the 3-month average SSTs holding at these levels for five consecutive months (with an accompanying El Niño-like atmospheric response). A surge of enhanced east-to-west blowing trade winds is predicted for the west-central Pacific over the next two weeks, and these stronger-than-average trade winds will interfere with any progression towards El Niño.
NOAA forecasters gave a 35 - 45% chance of an El Niño event occurring this year—a slight downgrade from their previous month’s forecast, which gave a 35 - 50% chance. El Niño conditions tend to suppress Atlantic hurricane activity by bringing strong upper-level winds to the tropical Atlantic, creating high wind shear that tears storms apart. A reduction in the odds of El Niño boosts the odds of an active Atlantic hurricane season.
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| Figure 2. Sea surface temperatures (SSTs) in the benchmark Niño 3.4 region (in the equatorial Pacific) have been hovering at about 0.5°C above average for most of June and early July, right at the 0.5°C above average threshold for weak El Niño conditions. Image credit: Levi Cowan, tropicaltidbits.com. |
Arctic sea ice extent sixth lowest on record for June
Arctic sea ice extent during June 2017 had the sixth lowest extent in the 38-year satellite record, according to the National Snow and Ice Data Center (NSIDC). The total volume of the ice was at record low levels for June in 2017, and sea ice extent was virtually tied with the extent observed in June 2012, which ended up the lowest sea ice extent on record in September. The GFS model is predicting that low pressure and cloudy skies will predominate in the Arctic over the coming two weeks, which should keep ice extent from reaching a record low for the month.
Antarctic sea ice extent second lowest on record for June
Sea ice surrounding Antarctica was at unprecedented lows in recent months, setting an all-time monthly minimum extent record each month during the five-month period November 2016 – March 2017. However, monthly Antarctic sea ice extent in both April, May and June of 2017 were the second lowest on record for their respective months. But by the end of June 2017, Antarctic sea ice was at record-low extent again. A recent study by John Turner and colleagues links the recent Antarctic sea ice decline to a series of strong storms accompanied by long periods of warm winds from the north. These changing weather conditions are associated with large shifts in the Southern Annual Mode (SAM) index.
Notable global heat and cold marks set for June 2017
Hottest temperature in the Northern Hemisphere: 53.7°C (128.7°F) at Ahwaz, Iran, 29 June
Coldest temperature in the Northern Hemisphere: -28.2°C (-18.8°F) at Summit, Greenland, 6 June
Hottest temperature in the Southern Hemisphere: 38.0°C (100.4°F) at Picos, Brazil, 10 June
Coldest temperature in the Southern Hemisphere: -83.9°C (-119.0°F) at Concordia, Antarctica, 20 June
(Courtesy of Maximiliano Herrera.)
Major weather stations that set (not tied) new all-time heat or cold records in June 2017
Hanoi Lang Observatory (Vietnam) max. 41.5°C, 3 June; beaten again with 41.8°C on 4 June
Hanoi Ha Dong (Vietnam) max. 42.0°C, 3 June; beaten again with 42.5°C on 4 June
Lang Son (Vietnam) max. 40.8°C, 4 June
Dera Ismail Khan (Pakistan) max. 51.0°C, 4 June
Mezaira (United Arab Emirates) max. 52.5°C, 16 June; New national record high
Zahedan (Iran) max. 43.4°C, 23 June
Ahwaz (Iran) max. 53.7°C, 29 June; New national record high (under standard conditions); also the new highest temperature ever recorded in Asia in June
(Courtesy of Maximiliano Herrera.)
Two all-time national heat records set in June 2017
As noted above, two nations (Iran and the United Arab Emirates) set their all-time records for hottest temperature in recorded history in June 2017. As of July 17, eight nations have set or tied all-time national heat records in 2017, and two have set or tied all-time cold records. Most nations do not maintain official databases of extreme temperature records, so the national temperature records reported here are in many cases not official. I use as my source for international weather records researcher Maximiliano Herrera, one of the world's top climatologists, who maintains a comprehensive list of extreme temperature records for every nation in the world on his website. If you reproduce this list of extremes, please cite Maximiliano Herrera as the primary source of the weather records.
All-time national heat records set or tied in 2017:
Iran: 128.7°F (53.7°C), at Ahwaz, 29 June
United Arab Emirates: 126.5°F (52.5°C), at Mezaira, 16 June
Oman: 123.4°F (50.8°C), at Qurayyat on 30 May and at Joba on 31 May (tie)
Pakistan: 128.3°F (53.5°C), at Turbat on 28 May (tie)
Guinea: 113°F (45.0°C), at Koundara, 29 March (tie)
Ghana: 110.8°F (43.8°C), at Navrongo, 26 March
Chile: 113°F (45.0°C), at Cauquenes, 26 January
Cocos Islands (Australia): 91.2°F (32.9°C), at Cocos Island Airport, 23 February
All-time national cold records set in 2017:
United Arab Emirates: 22.3°F (-5.4°C) at Jabel Jais, 3 February
Qatar: 34.7°F (1.5°C) at Abu Samra, 5 February
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