Friday, September 19, 2014

After the frost - a warmer weekend ahead

Not a very dramatic photo, but it does tell the story, frost on this last week of summer. The temperature dipped to 1C (33F) on L'Ile Perrot this morning with patchy frost around, two to three weeks ahead of the average date.
After we get the nonsense of this first frost out of the way, it looks like the weekend will be much warmer. Fall does not arrive until Monday but the geese are heading south this morning, and I wish I could join them. Temperatures under clear skies dropped quickly last night, but a northeast breeze saved us here in Montreal from widespread freezing temperatures. The low on L'Ile Perrot was 1C (33F) just after 4am. The mercury dropped to -1C (30F) in Cornwall, -3C (27F) in Kemptville, and a very cold -5C (23F) in St Jovite, 1 hour north of Montreal. There is patchy frost on the ground here in the city, and a coating of thin ice on some windshields including mine. Other regions around us were much colder as noted, with several hours of freezing temperatures including the Adirondacks, Laurentians, Townships and rural eastern Ontario. Lows in those regions ranged from 0 to -5C.

We will recover nicely today under sunny skies with highs near 14C (56F). Clouds will be on the increase tonight as a warm front moves into the St. Lawrence Valley. The front will bring scattered showers on Saturday, it will be windy and warmer with highs near 22C (72F). Most of the day will be dry and great for outdoor activities. By Sunday a cold front will bring more general showers, a wet and cloudy day can be expected, but it remain mild, near 22C.

Thursday, September 18, 2014

Frost Advisory for Southern Quebec - NY & Vermont

Our average frost in Montreal typically does not happen until the first week of October on average. But here we are, the last week of summer 2014, and is it not fitting that we have a frost advisory in effect. The entire region is under the advisory with the exception of metro Montreal near the St. Lawrence River and the Richelieu River Valley. A cold front has slipped south of Montreal early this morning. The front produced between 4 and 5mm of rain overnight and now a stiff northerly wind will develop along with steady or slowly falling temperatures. The high here on L'Ile Perrot was 13C (55F) at midnight and we have been falling since. It is currently a chilly 9C (49F). Look for partly sunny skies today and clear skies tonight. Temperatures will fall tonight to around 0C (32F) in most regions of southern Quebec but as cold as -2 to -4C in the Townships and Laurentians. The same cold conditions can be expected in Eastern Ontario and northern New York and Vermont. Freeze and frost advisories/warnings are in effect in those areas as well. We will see sunshine on Friday with temperatures a little warmer, near 13C (55F). Low pressure will affect Montreal over the weekend with showers developing Saturday and lasting into Sunday. It will be much milder with temperatures near 20C (68F) both days.

Monday, September 15, 2014

Below normal temperatures to continue in Montreal

The sun breaks through the clouds early Sunday morning on Mount Washington, NH. It was a sign of the seasons as cold temperatures produce rime ice and there was even some freezing rain over the weekend.
This is the last full week of summer, but if you stepped outside at any point this weekend, you would think it has checked out already. It was a weekend more suited for mid-October, with cold temperatures, lots of cloud cover, and at times heavy rain on Saturday. Saturday produced 15-25mm of rain across southern Quebec, far more than I was expecting. What should have been spotty showers, turned into a deluge through the middle afternoon. I recorded 18mm here on L'Ile Perrot. The clouds and rain kept temperatures cool with highs near 13C (55F) well below the normal of 19C (66F). Sunday was a touch better, dry, but just as cold with highs near 11C (52F) and lows near 4C (39F).

We nearly had frost early this morning here on L'Ile Perrot with the temperature bottoming out at 2.8C at 3am. The coldest readings were observed across the Townships with several reports of 0C. Clouds and fog developed after that point helping the temperature to warm a few degrees to 7C where we sit now. The week looks rather unsettled but with a very slow warming trend, and by Saturday we should be back to normal, 20C. In the short term clouds today with some sunshine and much warmer highs of 17C (63F). Overnight will be milder but with showers developing that will persist into midday Tuesday. By Wednesday skies should clear out but it will be cool once again with high in the lower teens. The next risk for frost will come by early Thursday morning as lows again head towards 0C across southern Quebec and eastern Ontario.

Thursday, September 11, 2014

After the rain - cooler weather for Quebec & Ontario

Fire crews responded to hundreds of downed trees and power lines in Calgary on Wednesday. I really hate the idea of snow pictures on the blog in September but what can you do. Mother nature continues to shock southern Alberta with snow and cold weather. (CBC News)
While the temperature edged close to 27C (81F) in Montreal on Wednesday, snow fell once again across southwest Alberta, edging into parts of the Cypress Hills in Saskatchewan and south into Montana, Idaho, Wyoming and South Dakota. 
The freak snowstorm out west knocked down hundreds of trees in Calgary under the wight of nearly 20cm (8 inches) of wet snow. This was the second snowstorm in as many days with cold temperatures running as much as 20 degrees below normal. The downed trees in many cases took down power lines creating massive power outages across southwest Alberta. The power is slowly being restored. The snow has now spread south into Montana, with up to 1 foot of wet snow forecast in some localities today.

Meanwhile Montreal basked in warm sunshine, even a touch humid ahead of strong cold front that already started across the region this morning. That front brought clouds and showers overnight with about 7mm of rain here on L'Ile Perrot. Radar shows more showers off to the west in Ontario so the threat will remain into early afternoon before ending. Winds are picking up as well ahead of the cold front, out of the southwest up to 50km/h. They will gust to 70km/h in the St. Lawrence Valley by the middle afternoon and diminish this evening. The temperatures of 17 to 20C this morning will remain nearly stationary for most of the day perhaps gaining a degree or two if the sun pops out this afternoon. It will clear this evening with cool lows down to 8C (47F). Look for a fall like day Friday with partly cloudy skies and temperatures near 17C (63F).

On Wednesday the aforementioned cold front brought heavy rain and thunderstorms to southern Ontario. As much as 100mm (4 inches) of rain fell in Amherstburg, 64mm in Windsor, 67mm in London and 27mmm in Toronto.

The 9-11 Memorial in New York City. Please take time to remember today.

Tuesday, September 09, 2014

Perfect weather in Montreal - snow in Calgary

Crazy summer snow in Calgary on Monday as between 10-20cm of wet snow fell. More is forecast Tuesday night before a warming trend arrives. (The National Post).
While it was 25C (77F) with bright sunshine in Montreal on Monday, snow was falling across central and southern Alberta. Southern Quebec had a nearly perfect weather day, moderate temperatures, low humidity and bright sunshine. It was clear and calm overnight for viewing the full harvest moon, a super moon at that. The weather will hold today as high pressure crests over the region. Temperatures will once again warm to 25C. Clouds will begin to move into the region on Wednesday as a cold front approaches from the west. It will be windy with a steady rain and much cooler temperatures on Thursday, 18C (65F) before an October like air mass arrives for Friday into the weekend. Temperatures on the weekend will be down to 5 to 8C at night and only 16 to 18C during the day.

That same front produced a breezy, unseasonably cold day with snow on Monday in Alberta. Accumulations of 20cm was reported in northwest Calgary, 18cm fell at Bow Valley,  9cm at the airport in Calgary, while Edmonton had 2cm. Frost and cold temperatures followed the snow with Calagry at -1 (30F) this morning. Another Pacific front will bring more snow tonight across the foothills of Alberta. Environment Canada has posted another snowfall warning for the city of Calgary with a forecast 10-15cm possible from late Tuesday into Wednesday morning. Temperatures will range from -1 to 3C. A big warm up is forecast by the weekend with highs near 24C (76F) by Saturday!

Monday, September 08, 2014

Fall is in the air

A shot of lightning illuminates my otherwise very dark street at 10pm Friday night. The storms produced the most vivid lightning of the season here on L'Ile Perrot. (ValleyWX)
It was a decent Sunday across southern Quebec after a stormy Friday and wet Saturday. Around 20mm of rain fell here on L'Ile Perrot through Saturday afternoon, most of that in thunderstorm activity late Friday. Much less fell at Trudeau Airport with about 8mm. Friday was hot with temperatures between 31C and 33C (88-92F) in Montreal. The storms on Friday were intense at times with frequent lightning and gusty winds. Behind the front much cooler and dry air moved into the region with temperatures down to 10C (50F) by Sunday morning, and again this morning with patchy fog around. The start of the week looks perfect with seasonable temperatures and sunshine.

Looking ahead we see more of a fall like pattern developing across Canada as the week prevails. The warm and humid air has been pressed to the south and is being replaced by a northwest flow of cooler air here in Quebec. Temperatures through Wednesday will be around 24C (76F) for highs with cool nights down to 10C (50F). By Thursday a cold front will introduce showers and much colder air.

How cool will it get? Well this morning radar and traffic cameras across central and southwest Alberta are showing snow. Parts of west Edmonton into Spruce Grove are down to the freezing point with a slushy accumulation of snow, yes snow in the summer! The snow is falling on the back side of a low pressure area moving into Saskatchewan. Snow is forecast as far south as Calgary into this evening with 5cm possible. Across the foothills, warnings are in effect for up 15cm of wet snow from Banff to Jasper and west to the B.C border. Elsewhere frost and freezing temperatures will occur including in Saskatchewan where the harvest is well underway.

I don't expect it to get that cold in Montreal, but we will have single digit overnight lows by Friday and into next weekend with daytime highs only in the middle teens.

Friday, September 05, 2014

Hazy hot day - cooler weekend

Hearing from a few of my friends and colleagues that they are ready for fall. What? To each their own I suppose, but we clearly need more summer, it arrived late, it was just like that, and now it appears to be taking an early exit, especially across the west. Snow and frost across Alberta already this week with more cold weather in store for next week.

NOAA update showing the expected cold weather next week.

That being said we are in for a very warm day with near record breaking warmth in Quebec and we should see some new records posted in Ontario. Temperatures are already in the mid 20's and we are looking at 29 to 33C (85-92F) for most regions. The record high for Montreal is 33.3C set in 2008, we have an outside chance of it in the city but the airport has been notoriously cool this summer, as already stated in previous blogs, so just reaching 30C (86F) at Trudeau may be a lofty goal. It will also be windy today out of the southwest ahead of the sharp cold front, gusting to 60km/h in the St. Lawrence Valley. The forecast heat and humidity has prompted warnings across southwest Ontario and special weather statements here in Quebec. Humidex values may approach 40C by this afternoon.

Sunshine and humidity will build, with increasing clouds by late in the day. Thunderstorms will develop along that potent cold front later this afternoon in Ontario and across Quebec by late this evening. Some of the storms may be severe in Ontario. On Saturday, skies will slowly clear and it will be much cooler with highs of 21C (70F). Sunday looks sunny and seasonable with overnight lows of  10C (50F) and highs near 22C (72F).