After days of anticipation, the chances of snow accumulation this weekend have disappeared. But some model predictions suggest that the threat of a winter storm, with significant icy precipitation, is increasing next week.
Rainfall on Saturday and Sunday does not have the impact. Saturday's event will probably make us forget the south, as precipitation can not even reach the north of the district. Our southern region, in particular, could see light rain or snow not accumulate, mainly in the morning, but it is essentially a non-event.
A slight disturbance westward Sunday could bring light rain showers in the afternoons and evenings. We can not exclude a bit of mixed precipitation, mainly in our coldest regions, but that should not be much.
From Tuesday to Thursday
The period from Tuesday to Thursday late presents a meteorological threat for the winter that must be monitored. It could become a major storm with a significant accumulation of snow and / or ice, especially in our coldest regions.
The models predict strong pressure on southeastern Canada, perched in a suitable location to introduce cold air into the region, while low pressure, coming from the Gulf of Mexico, results in a great deal of pressure. moisture northward as it emerges from the south.
European and American models suggest that snow could form late Tuesday night early Wednesday morning as the storm approaches.
The question is how long does the snow last Wednesday before eventually moving to ice and rain.
The US model predicts a faster transition, with light snowfall before a brief period of mixed precipitation and then rainfall. Its forecasts would mean more of a minor weather event in winter.
The European model however suggests that the cold air will hold longer. It predicts heavy snowfall Wednesday afternoon, especially north and west of the district, before a long period of slush and freezing rain that can last until Wednesday night. .
The predictions of the European model, at face value, would represent a snow and ice event with a high impact for the region. In his modeling system of 50 simulations, 80% predict at least three inches of snow in the immediate area before switching to ice and / or rain.
The predictions of the Canadian model, not shown, are in a way a mixture of American and European models, more oriented towards American models.
On the basis of past performances, we would look for the time at the European model forecast, more winter, although many may change with the storm in five days.
Forecast forecasting depends on the rate at which precipitation is moving relative to the cold high pressure system in the north, which weakens and slides towards the east. If the maximum stays in place while rainfall covers the area, our chances of having a disruptive winter storm increase. Reduce height and drag quickly east, and the storm could turn into rain, except in the colder areas north and west of the city, where ice could be formed.
The only thing we are sure of is that a storm will rise on the area late Tuesday, which will spread the precipitation until Wednesday. And the amount of rainfall will probably be substantial.
The details will come to light over the next few days. Stay tuned for updates.