Weather tracker: North-west US hit by snow ahead of eastern heatwave

Unseasonal snow fell in parts of the north-west US after a strong cold front moved in from the northern Pacific, bringing an abrupt change to a region that had been experiencing high summer temperatures amid drought. Temperatures from the Canadian border to California have been widely 5-10C below the norm since Friday, and more than 10C below in some parts farther north, a pattern expected to remain for much of the coming week.

The front delivered the first significant rainfall in weeks to several north-west areas and, across the Rocky mountains in Idaho, Montana and Wyoming, combined with the unseasonal cold to produce snowfall at unusually low elevations. Whereas the summer snow line typically sits at about 3,300 metres (11,000ft), snow fell as low as 1,800 metres on Sunday, with more due to fall on Monday and several inches expected to accumulate at higher altitudes.

Counterintuitively, the cold front has heightened the wildfire danger.

United States, Northwest US

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