The global average land temperature reached 11.2 degrees centigrade, 0.96 degrees above the month's average, while the combined global land and sea average for May was the second highest since observations began in 1880, according to WMO.

Record high temperatures in parts of western Europe in June also fitted into an accelerating trend of extreme weather conditions in recent years, the UN's weather agency said.

But it stopped short of blaming global warming for the hot weather, and would only say in a statement released here that such extremes "might" increase as a result of climate change.

Global data for the past month was not yet available.

A WMO meteorologist explained that on a global scale exceptionally hot weather in Europe in June had to be balanced against cooler than usual weather in the eastern half of the United States.

Switzerland experienced its hottest month of June for 140 years, while peaks above 40 degrees centigrade across southern France raised temperatures to five to seven degrees centigrade above the long-term average there, WMO said

"New record extreme events occur every year somewhere in the globe, but in recent years the number of such extremes have been increasing," the statement noted.

WMO also highlighted a record 562 tornadoes during May in the United States, exceeding the previous monthly record of 399 in June 1992.

At least 1,400 people died in India in a pre-monsoon heat wave which drove temperatures up to 49 degrees centigrade, raising weekly temperatures five degrees above normal.

WMO said extremes contributed to warnings from scientists on the Intergovernmental Panel for Climate Change (IPCC) in recent years that global warming was underway.

The IPCC also found that the rise in global average land temperatures this century had accelerated three-fold since 1976.

US President George W. Bush has questioned the scientific evidence for global warming, which has been blamed on the impact of pollution from greenhouse gases produced by burning oil and coal.

SPACE.WIRE