WASHINGTON • The US saw the warmest June since 1895 last month. It surpassed the 1933 record and capped a six-month period which saw eight weather-related disasters that caused US$1 billion (S$1.35 billion) in damage or more each.
The average June temperature across the 48 contiguous states was 22 deg C, the National Centres for Environmental Information said in a report on Thursday.
The first six months were also the third-warmest in the US, while Alaska experienced its hottest six months on record, breaking a mark set in 1981.
Global temperatures were the highest in the 20th century for the first five months of the year after the world posted its two hottest years in 2014 and 2015.
There is so much heat in the atmosphere following the El Nino that started last year that 2016 could well set a new all-time high.
"This was the warmest first five months for the global surface by a wide margin," said Mr Jake Crouch, a climate scientist for the agency. "We expect those record warm temperatures to persist even though El Nino is over."
El Ninos, which can occur every two or three years, warm the surface of the Pacific, which in turn tends to raise global temperatures.
While the phenomenon does not cause climate change, it can contribute to warming. El Nino ended earlier this year. From June last year to May this year, the world had its warmest 12-month period, according to Mr Kevin Trenberth, a distinguished senior scientist with the National Centre for Atmospheric Research.
While he doubts the second half of 2016 will be as warm, it could still end up setting a record.
Hot, dry conditions across the West "entrenched" the drought in California, now in its fifth year, according to the report.
It also helped spur several major wildfires, including Southern California's Erskine fire that charred nearly 19,500ha, destroyed 280 homes and killed two people. The Northern and Central Plains, Midwest and North- east were also hot and dry, while Massachusetts, Rhode Island, Nebraska, South Dakota and Wyoming had little rain last month.
Just over 44 per cent of the US is abnormally dry or in some form of drought, according to the US Drought Monitor in Lincoln, Nebraska.
Meanwhile, rains last month caused floods in West Virginia that killed at least 23 people and destroyed 1,500 homes.
The Mid-Atlantic states, South-west and Southern Plains all had above-average rain for the month. June rainfall for the US was 6.25cm, 1.2cm below the 20th century average. For the year, precipitation was 39.6cm, 0.7cm above average.