Polar vortex gives way to ‘milder’ weather

THE polar vortex that locked the US Midwest in sub-zero weather and led to the deaths of at least 21 people will give way to milder, snow-melting temperatures this weekend.

Temperatures should reach the mid 40s to low 50s Fahrenheit (4-5ºC), forecasters said, after a record-breaking cold snap that stopped postal service and shuttered schools and businesses.

The polar vortex is an icy cap of air that usually swirls over the North Pole. Changing air currents caused it to slip down through Canada and into the US Midwest this week.

“The cold air isn’t pushing off anywhere, it’s just sort of evaporating,” said Brian Hurley, a meteorologist with the National Weather Service’s Weather Prediction Center in College Park, Maryland.

“So we’re going from 21 below zero (Fahrenheit) in Chicago Thursday morning to near 50 above on Monday,” he said. “It’ll feel like a heat wave”.

Meanwhile in other extreme weather, Australia sweltered through its hottest month on record last month and the summer of extremes continued with wildfires razing the drought-parched south and flooding in expanses of the tropical north.

Australia’s Bureau of Meteorology confirmed the January record on yesteday as parts of the northern hemisphere had record cold.

Australia’s scorching start to the year – in which the mean temperature across the country for the first time exceeded 30ºC – followed Australia’s third-hottest year on record. Only 2005 and 2013 were warmer than 2018, which ended with the hottest December on record.

Heat-stressed bats dropped dead from trees by the thousands in Victoria state and bitumen roads melted in New South Wales during heatwaves last month. |

| TARA WALTON CANADIAN PRESS WATER flows over the frozen American Falls, seen from the Canadian side in Niagara Falls, Ontario this week.