That four-letter word is back across parts of Quebec - SNOW!

The calm after the storm on Friday, October 2. Morning rain and gusty winds gave way to a spectacular sky by day's end. (ValleyWeather)

A strong cold front has cut across the province early Monday morning, ushering in the coldest airmass of the season so far, on gusty northwest winds. High temperatures have been reached already, around 13C (55F), with the mercury expected to fall into the single digits, as low as 5C (41F) by Tuesday morning for Montreal. Along with the chilly air will be northwest winds in the 30-50km/h range. Parts of the province north of Montreal, including the higher elevations of the northern Laurentians may see the first snowflakes of the year, as well as the mountain peaks towards the Vermont border.

Don't panic just yet in Montreal, but now is the time to plan. I have my winter tire appointment booked already at Gordons in NDG, no point in avoiding the inevitable.  There is often a sharp contrast from September into October across Quebec and Ontario. September for the most part is just another summer month now. Weather conditions change rather abruptly in October, with the average high dropping from 16C (61F) at the start of the month, down to 9C (49F) by Halloween. Average lows drop to near the freezing point by months end.

More construction in Montreal as this ghoulish crew assembles a Halloween display on Ile Perrot. October weather is in sharp contrast to September, with frost, northwest winds and usually our first snowflake or two occurring. Time will tell what a Super El Nino October has in store for Montreal. (ValleyWeather)

This past September was not unusually warm, but we still managed an average temperature of 16.6C, which was 0.6 degrees above normal at Trudeau Airport in Montreal. September was very dry across the province of Quebec, with many regions running significant moisture deficits. Montreal measured only 50.6mm of rain, most of that falling on September 8-9. The long-term average is 89.2mm.

Montreal can expect a variable week, blustery and chilly to start, a brief warm up midweek, followed my clouds and cooler temperatures by Friday. Typical October weather for southern Quebec, with a vibrant mix of sun and clouds against the backdrop of vivid foliage that is starting to spread quickly. 

Clouds and showers are possible midweek, but no major weather systems are expected. The gusty northwest winds will likely prevent frost from forming in Montreal on Monday and Tuesday, but regions northwest of the city may see frost Tuesday morning.