Big snowstorm for western Plains - warm in the east

A potent low pressure area will develop today across the northern Rockies and swing into the central plains tonight. This system has already produced 3-7cm of wet snow over portions of southwest Alberta into northwest Montana. The storm will ramp up later today and tonight with rain changing to heavy wet snow across the Black Hills of South Dakota west into Wyoming as well as portions of North Dakota. Forecasters expect 12-24 inches (30-60cm) of wet snow by the end of Friday with strong northerly winds producing blowing and drifting snow. Power lines and trees will be subject to the heavy weight of the snow as well as the wind.

The storm will lift into the western Great Lakes by the weekend with a chance of some snow over northwest Ontario. Meanwhile here in southern Quebec and Ontario, today is day 11 of sunshine and above normal temperatures. We hit 25C (77F) in Montreal on Wednesday, and should do 22C today. Some showers are likely by late Friday into Saturday. Wet weather can also be expected to start next week, but it will remain warm for October.

We should have the development of tropical storm Karen at some point today. The National Hurricane Center is giving an area of disturbed weather and thunderstorms near the Yucatan an 80 per cent chance of development. Karen will then threaten the Yucatan as she moves into the southern Gulf. All interest along the Gulf Coast should monitor the progress of this system today and into the weekend.