Thursday, April 29, 2021

Extended period of wet weather forecast for Montreal

Rainy, damp weather is anticipated for the next 5 to 7 days across southern Quebec, with the only break coming on Saturday. The forecast rainfall will help return the region to near-normal precipitation for April.

We are making up for lost time in Montreal, after a very dry March and first half of April, the rain has returned to southern Quebec. Cooler, wet weather is anticipated on Friday and into early next week. On Wednesday, 5.4mm of rain fell at Trudeau Airport, bringing the monthly precipitation up to 47.2mm. The month started with 13 consecutive dry days. The normal precipitation for the month is 82.2mm, which usually includes 12.9cm of snow. Snow however has been sparse this Spring, Montreal has only received a 7.6cm of snow since March 1st.  

Thursday is expected to be mostly cloudy, with a few sunny breaks and a mild high temperature of 17C (63F). Clouds will thicken this afternoon and rain will begin this evening as low pressure moves from the Ohio Valley to theAtlantic coast. Abundant moisture is forecast to spread northward across New York and New England today and into southern Quebec. Expect a steady rain overnight in Montreal, tapering to showers Friday afternoon. Rainfall amounts will range from 20 to 30mm across southern Quebec, bringing Montreal very close to the normal precipitation for April. 

Showery, foggy weather will persist into the evening hours across the region, with even a few flurries mixing in at the higher elevations along the US border. Low temperatures will remain close to 10C (50F). The high will be much cooler on Friday, remaining steady near 10C, but dropping slowly in the afternoon. Winds will become quite strong from the west up to 60km/h in the afternoon. It will be a blustery, cold, damp day to start May.

Nicer weather returns for the first half of the weekend, with Saturday being the best day of the next 5 or 6 days. Expect partly sunny skies, but breezy and cool, with a high of only 10C (50F). Rain returns on Sunday, with scattered showers forecast for Monday through Wednesday.

Friday, April 23, 2021

Warmer weather to follow record snowfall in Montreal

The 5cm of snow that fell on Montreal on Wednesday was the most on April 21 in over a century. (ValleyWeather Photo)

After a very warm spring to date, residents of southern Quebec and Ontario were shocked by several centimetres of snow that fell on Wednesday and Thursday. It is not often the case here in Montreal that more snow falls in April than in March, but that is how the weather turned out in 2021. The 5cm of wet snow that fell on the city Wednesday set a new daily record. There has not been that much snow on April 21 in over 100 years, dating back to 1905. The 2cm of snow that remained on the ground Thursday morning, was the deepest snow measured at Trudeau Airport for any April 22 since 1955. Only 2.2cm of snow fell in Montreal the entire month of March.

Brief, intense snow squalls swept across the island of Montreal on Thursday morning. The quick burst of snow caught many motorists off guard, with numerous accidents reported, especially off-island to the west. (ValleyWeather Photo)

Snow squalls on Thursday morning were actually more disruptive than Wednesday's snow, especially in the western portion of Montreal and off island towards the Ontario border. A quick layer of snow coated roads and produced black ice during the morning commute. There were several major accidents reported. The snow showers tapered off in the afternoon, but the weather remained windy and cold.

Conditions have improved greatly on Friday, as the snow has melted, and temperatures are into the low teens. Low pressure remains to our northeast, so the winds are still gusting up to 50km/h. High pressure will give us a sunny, much warmer Saturday, with highs back into the upper teen and light winds.

A frontal boundary will approach southern Quebec on Sunday, with a renewed chance for showers and perhaps a thunderstorm. Temperatures will be near normal, with a high of 15C. We can expect temperatures to be cooler on Monday, but quickly warm back up to the upper teens and even lower 20s next week.

Monday, April 19, 2021

Spring snow on the way for Southern Quebec

Workers defy gravity as they begin to break up the winter snow piled several storeys high at the St Laurent dump on Thimens Boulevard. Colder weather this week and even the potential for some snow by Wednesday, should temporarily slow the melting process. (ValleyWeather Photo)

If you are one of the few who had hoped to see snowflakes fly just one more time in Montreal, then you are in luck. Otherwise, turn away now from this forecast. After what has been a fairly warm month, we are looking at the potential for accumulating snow this Wednesday.

The coastal system that impacted southern Quebec and new England on Friday, produced quite a bit of wet snow across the Townships and interior New England, however precipitation remained as rain for Montreal, with 25-35mm falling across the city. Colder air settled into southern Quebec for the weekend, under partly cloudy skies.

The storm in question is expected to develop south of the Great Lakes and move just south of Montreal on Wednesday. Colder air filtering into the region will change the rain to snow late Wednesday. (AccuWeather.com)

We are in for a mild start to the week, reaching 17C (63F) in Montreal on Monday, before a frontal system arrives late in the day. A few showers are possible this evening along with a rumble or two of thunder. Cooler, windy weather is forecast for Tuesday, with highs near 10C (50F) and winds up to 50km/h. The weather will turn quite active on Wednesday, as low pressure approaches from the Ohio Valley. The storm is expected to move across the southern Great Lakes and into northern New England on Thursday. A narrow swath of wet snow is forecast to fall along and just north of the storms track impacting southern Ontario and Quebec. At this time, rain is expected Wednesday in Montreal, changing to wet snow during the evening hours and ending early Thursday. Amounts are very difficult to predict at this time of year, and will depend heavily on when the changeover occurs as well as local elevation. There is a chance of 5 to 10cm of slushy wet snow along and just north of the St. Lawrence River.

While we have not had much in the way of snow since late February, it is not that unusual for Montreal to have snow in April. As a mater of fact the reverse is actually true, it has been rather rare in 2021 to not have any snowfall during March and April. A quick look at the statistics form Trudeau Airport shows that you have to go back to 2005 to find a year with no snow in Montreal in April.

Temperatures will be cold on Wednesday and Thursday, expect highs around 3C (37F) and low temperatures at or just below the freezing point. With the very mild weather we have experienced over the last two weeks, many trees and shrubs have started to bud or flower. The wet snow, frost and cold will not be good for any flowering plants. The good news is that temperatures will warm again quickly into next weekend, with highs back into the middle teens.

Wednesday, April 14, 2021

Rainy - cooler weather on the horizon for Montreal

Weather conditions have been extremely dry across southern Quebec, with only 0.4mm of precipitation falling at Trudeau Airport since April 1st. We do need the rain, and can expect 20 to 30mm on Thursday and Friday. The clouds and precipitation will result in much cooler temperatures than we have had recently.

The weather so far this April has been spectacular. Over the past week in Montreal, temperatures have been well above the long-term average, along with abundant sunshine. We can thank a blocking pattern over the North Atlantic that has managed to keep any adverse weather at bay. The storm track has been primarily to our west over central Ontario as well as across Atlantic Canada. Those regions have had a miserable April to date. Heavy snow and cold weather is occurring across the Prairies, while heavy rain, freezing rain and snow battered Newfoundland this week.

The weather however has been exceptionally dry in Montreal, with no precipitation since the wee hours of April 1st. For the month to date, a paltry 0.4mm of rain has fallen, along with a trace of snow. That is all about to change as an upper level low is forecast to move across northern New England over the next 24 hours. A general increase in clouds tonight, will be followed by rain on Thursday, persisting into Friday. We can expect a widespread soaking rainfall, with 20 to 30mm possible for Montreal. A second area of low pressure at the surface is expected to develop and move along the eastern seaboard into Maine on Friday. This storm system may even produce a period of wet snow across New England. Winter storm watches have been hoisted for southern Vermont as well as portions of New Hampshire and Maine. I am not expected any snow in Montreal.

The clouds and precipitation will however result in much cooler temperatures across southern Quebec, more inline with what you would expect for mid-April. Over the last week daytime highs have been running in the mid-teens to low 20s. The normal high and low for Montreal should be 11C (52F) and 1C (33F) respectively. On Thursday the high will be 10C (50F), even cooler Friday, with a high of 7C (45F). The weekend will remain unsettled and cool, with clouds and showers Saturday and perhaps some partial clearing by Sunday. There is even a risk of scattered frost this weekend in Montreal, as lows dip to near the freezing point.

Monday, April 05, 2021

Near-perfect early spring weather for Montreal

A spectacular spring sunset over the St. Lawrence River. The lack of precipitation this spring, combined with a very slow thaw, has resulted in no flooding to date. Water levels are being monitored, but are actually forecast to drop over the next few days on both the Lake of Two Mountains and Lac St. Louis.
High pressure will dominate the weather picture for the upcoming week across southern Quebec. Stubborn low pressure over Nova Scotia will ensure a damp, cool week for Atlantic Canada and portions of eastern Quebec, while allowing high pressure to remain stationary over our region. Some shower activity may even drift westward into the Eastern Townships. As far as Montreal is concerned, we will have nothing but sunshine, along with increasing warmth.

Our snowstorm forecast for last Thursday turned out to be a non-event, as the system remained well to the east of Montreal. Portions of the Townships and Vermont reported as much as 10cm of snow, while Montreal managed less than 1cm. The sun returned by the end of the day followed by a very pleasant weekend, cold Friday and Saturday, but warming up nicely on Sunday.

The forecast for the week ahead is simple, sunny skies, with no precipitation expected. High temperatures will start the week in the lower teens, but rise to near 20C by Friday. Overnight lows will be 2 to 6C. 

The low relative humidity and gusty winds forecast for Monday, will mean an increase in fire danger. There is an abundance of dry leaves and other combustable material present, and any fire may quickly become out of control. Many areas are advising against outdoor burning, including southwestern Quebec, eastern Ontario and all of New York and Vermont.

The weather has been extremely dry across southern Quebec so far this spring. Only 2.2cm of snow fell in Montreal in March, a new record low. The previous record was 2.6cm set in 2009. Total precipitation for the month of March was 50mm, well below the normal of 69.1mm. So far April has only yielded 2.4mm. No rain is forecast through at least Saturday.