Tuesday, January 06, 2009

Winter Storm Warning

5pm UPDATE: I am happy with the forecast to this point. It appears we are on track for a major storm. Low pressure in the lower Mississippi Valley will move northeast and pass just south of Ontario and Quebec. Snow will spread into the region overnight from west to east and reach Montreal by daybreak. The snow may mix with freezing rain along the American border. Snowfall amounts will range from 15-30cm with a good 20cm expected in Kemptville and closer to 25cm for Montreal and Cornwall (the Seaway). Winds will be a factor in the St. Lawrence Valley and along the 401 corridor gusting from 30-60km/h causing blowing snow and reduced visibilities. Warnings are in effect for all our regions in Ontario, Quebec, northern New York and New England. Travel will be impacted by this system. Be prepared for very poor road conditions all day Wednesday and into Wednesday night. All precipitation will taper to flurries on Thursday.

12:00PM Update: Watches have been upgraded to warnings across all regions except areas along the immediate St. Lawrence River and Lake Ontario. Snow is expected to overspread the area this evening from the south and persist much of Wednesday with 15-20cm expected. The uncertainty along the St. Lawrence and points south is due to the type of precipitation expected which may lower the accumulations. Ice may mix with the snow over those areas. Travel will begin to deteriorate overnight, with the most intense snow occurring Wednesday from mid morning to mid afternoon. Travel may become quite difficult in snow and some blowing snow. It will turn colder with flurries on Thursday.

Winter storm watches are being hoisted across New York, New England, Ontario and Quebec as a new winter storm takes shape over the Gulf States. The low pressure area is forecast to move towards the St. Lawrence Valley on Wednesday before giving way to a new low along the eastern seaboard. The combination of the two systems will spread snow into the Kemptville area after midnight tonight with several centimetres expected by morning. The snow will reach Ottawa and Montreal overnight. On Wednesday all regions will receive steady snow with a mix along the St. Lawrence River and Great Lakes. Look for 10-20cm of snow in most regions. Travel on Wednesday will not be impossible but if you can delay or postpone do so.

Next statement around noon.

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