Thursday, July 24, 2014

Much cooler - less humid air arrives in Quebec

Lightning is believed to have sparked this fire in Derby, Vermont near the border with the Eastern Townships. Strong thunderstorms Wednesday brought an end to the heat and humidity across the entire region. (WCAX 3 News)
My vacation week is slowly melting away, not much going on this year as life has kept me from my usual trek to a beach...any beach. The heat and humidity that started the week has been chased out by Wednesday's cold front. Depending where you were in the region, that front either went through with a whimper or a bang. Thunderstorms in the early part of the day swept eastern Ontario, Montreal and southern Quebec with around 10-20mm of rain and frequent lightning. The storms managed to cut power to nearly 30,000 homes mostly off island in Vaudreuil/Dorion as well as in Stormont, Dundas and Glengarry County, Ontario. What had been a sultry night with temperatures in the middle 20's quickly became refreshed with the frontal passage. The same front produced heavy thunderstorms in Vermont and New York that cut power, knocked down trees and started several fires in homes. The storms were also responsible for yet another person injured by lightning this summer, this time at a campsite in Waddignton, New York near Massena.

The front pushed the hot weather to our south and east with highs only in the middle 20's in Montreal yesterday. Meanwhile the high heat was across Atlantic Canada with several record highs recorded as the mercury hit 30 to 32C. This morning Montreal is dry and much cooler at 17C (63F), quite a change from the low 30's of Monday and Tuesday. It will be a dry day with a northwest breeze and highs near 24C (75F). Clear and cool conditions expected tonight with lows around 14C (56F). Friday and Saturday look good with sunshine and highs near 26C (79F). We will see an increase in clouds on Saturday followed by a chance of showers late in the day and into Sunday. Sadly it looks cloudy, showery and cooler as we head into the last week of July. Another pool of much cooler than normal air will cross the Great Lakes and become established by early next week.

Monday, July 21, 2014

Warm & humid - strong thunderstorms Wednesday

The yellow arrows show smoke over Ontario drifting into Quebec and New England late last week and into the weekend. The haze and smokey air is travelling along the jet stream from wildfires burning in Alberta and B.C. (NWS Burlington)
Well almost immediately after I guaranteed a spectacular weekend on Friday, mother nature began to challenge that claim, at least for some of us. A colder than normal air mass over the Great Lakes managed to produced afternoon clouds and even some scattered showers over Ontario as far east as the Ottawa Valley. However sunshine and only some high cloudiness prevailed in Montreal. Temperatures responded in the sunshine making it to 28C (83F) on Sunday for metro Montreal, while it was only 23C (73F) in the clouds in Toronto. Another shot of much cooler than normal air will arrive in Ontario and Quebec and the US Midwest by Thursday but until then it will be very warm and humid. Partial sunshine can be expected both today and Tuesday in southern Quebec with just some high clouds and perhaps some haze and smoke form the western wildfires. Highs will make it close to 30C (86F) both days. On Wednesday a cold front will arrive with clouds and showers along with the risk of a few strong thunderstorms. Highs will be cooler reaching 26C (79F). By Thursday sunshine will return with a much drier and more comfortable air mass and highs near 22C (72F).

The moist, unstable air has Toronto down to 1 kilometer visibility in fog and mist this morning, with a special weather statement in effect for much of southwest Ontario for dense fog. The fog should burn off in the next few hours, but until then travel is slow with visibility locally as low as zero on some highways.

Friday, July 18, 2014

Nothing but sunshine for southern Quebec & Ontario

A beautiful rainbow over the West Island of Montreal last night signalling the end to a brief shower and the start of a spectacular period of weather! (ValleyWX Photo)
 Vacation time is upon us for many and the weather looks nearly perfect. A ridge of high pressure is slowly moving across the Great Lakes and into Quebec today with nothing but sunshine, light winds and low humidity forecast through the entire weekend. Temperatures will range from 27-30C (81-86F), as I said perfect!

The high pressure in question will very slowly drift across Quebec and into New England this weekend and eventually off the east coast. The return southerly flow will increase the heat and humidity next week with highs moving into the low 30's, close to 90F by Monday. The same forecast holds true for northern New York, New England and most of southern Ontario. No rain is expected before Wednesday of next week at the earliest. Be safe and enjoy!

Wednesday, July 16, 2014

Perfect stretch of summer weather for Montreal

A massive tree crushes a car in
York, Maine late on Tuesday
.
Ok, so I should have left my forecast alone yesterday. But I must admit the radar looked impressive in Ontario and most of us really thought Montreal would see a decent shot of heavy rain and thunder through the middle part of the day. As with so many other days this summer in Montreal, it was not to be with only about 2-3mm, a splash in the rain gauge occurring near the noon hour. Otherwise it was a cloudy, damp day with all the big storms staying either north or south of Montreal, same old story this year.

Tho storms managed to dump 20-30mm of rain is some portions of the Townships,  notably near Granby. They also produced very heavy rain across New Hampshire with flooding observed as well as severe weather over portions of coastal Maine and New Hampshire. York, Maine was particularly hard hit with trees crashing onto homes and cars late in the afternoon. Power poles were also snapped across the Seacoast with numerous outages.

HEAT & HUMIDITY BUILD
The forecast for southern Quebec is looking great as we head into the upcoming weekend and the start of a very busy summer vacation period in this province. There is a slight risk of a few showers today, but otherwise sunny through next Monday. Temperatures will be around 25C (77F) for highs today into Saturday with lows near 16C (61F). Temperatures will rise this weekend and into next week along with the humidity, with daytime highs easily reaching 30C (86F) by Sunday and perhaps 32C (90F) early next week.

Tuesday, July 15, 2014

Strong thunderstorms with heavy rain for Montreal

I know I promised quiet weather this week for metro Montreal, but first we have to get through Tuesday. What looked like only scattered showers from a low pressure area and cold front is turning into a rather large area of heavy rain with embedded thunderstorms this morning. Heavy rain warnings have now been posted for the St. Lawrence Valley from Kingston to the Ontario/Quebec border. A severe thunderstorm watch for pretty much the same reason is now in effect for metro Montreal and southwestern Quebec. The front is moving into very moist, unstable and humid air and will trigger heavy downpours. Between 25-75mm (1-3 inches) of rainfall is possible in a very short period of time today from about 11am unti late afternoon for Montreal. Temperatures will be muggy near 25C. (77F). The weather should begin to dry out and cool off by Wednesday morning.

Monday, July 14, 2014

Decent weather week for Montreal - record heat in BC

A quiet weather patter is setting up for the week ahead across southern Quebec and Ontario. Sunshine today will allow temperatures to warm to near 26C (79F). There is a little humidity leftover from the 13mm of rain on Sunday, but it should remain clear and dry. Weak low pressure along with a frontal boundary will cross the St. Lawrence Valley on Tuesday with scattered showers and perhaps a thunderstorm. It will be another mild day, around 24C (76F). The frontal passage will allow for some September like air to stream across the Great Lakes with a couple of days of natural air conditioning forecast. Temperatures will be in the low to middle teens at night and perhaps 21C (70F) during the day from Wednesday into Friday. As the high drifts offshore into the Atlantic, much warmer and increasingly humid air will move into southern Quebec by next weekend with sunshine and highs in the upper 20's to near 30C (86F) by Saturday.

Dense smoke from forest fires like this one near Kakisa in the NWT is lowering air quality across western Canada. (CBC News)
WESTERN HEATWAVE
The big weather news this week will be the hot and humid weather across the Pacific Northwest, BC and Alberta. Parts of interior B.C. near Osoyoos hit a record 40C (104F) on Sunday, Lytton also set a record at 41.1C (106F) with hot air streaming north from the deserts of the southwestern US. The hot weather will prevail all week with forecast highs from 35C to 40C (95-102F) through Friday. The hot, windy weather and lightning strikes have increased the forest fire threat with nearly 140 fires burning in the Northwest Territories alone. Over 50 fires are burning in British Columbia. The fires have sent a plume of smoke south and east across portions of Alberta, Saskatchewan and Manitoba over the last week producing very poor air quality. The record highs forecast this week in B.C. will not help the situation.

Friday, July 11, 2014

Bright Saturday - humid, showery Sunday for Montreal

The weekend is upon us once again on this Friday morning, we start the day in Montreal at a pleasant 16C (61F) on our way to 27C (81F). Nothing but sunshine and low humidity today as high pressure crests over the region. Clear tonight with lows around 17C (63F). Saturday looks sunny once again but with cloudy periods as winds pick up out of the southwest and the humidity begins to creep up. Temperatures will be warm as well, 30C (86F).

On Sunday the weather pattern begins to change as a deep trough develops over the Great Lakes with energy moving down the St. Lawrence Valley by Tuesday. A warm front draped across southern Quebec will be the focus for showers and thunderstorms from Sunday afternoon through Tuesday night. Some of the storms could be strong on Monday with heavy rain possible. It will clear out by Wednesday next week. Temperatures will be near or slightly below normal for the period at 25C (77F).