Warm west - cool east

Waterspouts are possible over the Great Lakes again today.

It is another chilly morning here on L'Ile Perrot with the temperature sitting at 15C (59F) after an overnight low of 13C (55F) around 6am this morning. We have some sunshine around as well as some mist and fog. As I have said all week, it feels more like a September morning than late July. Sadly my favorite month of the year is over, and it will end on a cool note with highs forecast near 21C (70F). A rather vigorous upper air disturbance will provide enough lift for scattered showers and thunderstorms today as it drifts from Ontario into New England. Some of the storms may have small hail and heavy rain. On Wednesday several decent storms affected the Ottawa Valley with over 23mm of rain for the nations capital. We may see similar amounts today, but not for everyone, they will be scattered in nature. Showers will taper off this evening followed by a partly sunny Friday and a little warmer, up to 25C (77F). The threat for some thunderstorms will still exist Friday afternoon for Montreal. The weekend at this time looks sunny and warm. Let hope it holds.

The cool weather this morning stretches all the way down to the Gulf of Mexico with record lows at Pensacola, Florida of 64F and Mobile, Alabama at 63F, one degree off their coldest July morning on record. The cool air aloft has produced numerous showers and thunderstorms over the Great Lakes, several that produced waterspouts on Wednesday. The threat is there again today especially over Lake Erie. Waterspouts are similar to tornadoes but generally weaker. They can certainly upset smaller watercraft.

Meanwhile it is warm in the west with temperatures once again soaring into the middle 30's. Bow Island, Alberta hit 35.2C (96F) on Wednesday while Calgary was 32C (90F). Calgary also had a rare heat burst in the early morning hours of Wednesday. Heat bursts occur from collapsing thunderstorms. Around 1am, a gusty southwest winds hit 85km/h at the airport with a dry dewpoint of 1C (humidity was less than 15%). Meanwhile the mercury shot up to 29C (85F), almost desert like.

Feels like September

I am not certain where our summer went but I hope it returns soon. Officially at Trudeau Airport, Montreal has managed only four 30C (86F) days this summer, two each in June and July. Only one day over 32C (90F) has occurred, that was July 1st. Last year we managed nine 30C or warmer days in July alone.

Major flooding in Chester, Vermont on Monday. (Chester Fire Department)

 It was just a cold, miserable day on Monday across southern Quebec. Our temperature only managed to reach 18C (65F) for a high and that was early in the day. Most of the afternoon we were stuck at 16C (60F) with a cold northeast wind and rain. I recorded 11.7 mm of rain on L'Ile Perrot with a two day total of 27 mm. Other regions to our south had much more with 25-50mm (1-2 inches) falling from the Townships south into Vermont. In southern Vermont major flooding occurred around Chester and Andover in Windsor County. The rain swelled rivers damaging roads and bridges as well as several homes. Power was cut to over 1000 customers. The low pressure responsible for the lousy weather is now in northern Maine with high pressure building in briefly today. Partly cloudy skies can be expected from eastern Ontario into Montreal along with milder highs of 23C (73F), still well below normal. Wednesday and Thursday will see more clouds with the chance of a shower or thunderstorm as the upper low remains nearly stationary over the Gulf of St. Lawrence. Temperatures will warm slightly to 25C (77F) but we will have the ever present chance of a shower or thunderstorm into the weekend.

Rainy & cool start to the week

A rather vigorous low pressure area for late July is centered near Rochester, NY this morning. The system has a large area of rain and thunderstorms pivoting around it, and that area will move into southern Quebec and eastern Ontario this morning as the low moves towards Sherbrooke. It should be a rainy and cool Monday with even the chance for thunderstorms, temperatures will only be near 20C (68F) today and down to 15C (59F) tonight. The rain will be rather impressive with 25-30mm, around 1 inch generally throughout the region. Heavy rain is forecast across the Townships along with embedded thunderstorms. A rainfall warning is in effect for the Beauce and Eastern Townships where 60mm could fall. The rain should end by midnight. The rest of the week looks unsettled with showers and thunderstorms possible with a very slow warming trend.

On Sunday Montreal had about 17mm of rain, mostly in thunderstorms to start the day and scattered showers in the evening. We managed a muggy high of 25C (77F).

Thunderstorms produced major flooding in Toronto last evening with several roads impassable. (Global News)

The same system drenched southern Ontario on Sunday with 50-100mm (2-4 inches) of rain in thunderstorms. High winds cut power, trees fell on homes and cars and even a funnel cloud was reported in the southwest. Flooding occurred last evening on several major GTA highways including the 401. The OPP took to Twitter to recommend drivers stay off the roads and definitely not drive through standing water. The photo shows above some did not head that advice.

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.

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.

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!

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.

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.

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.

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).

High winds leave 100,000 Quebec homes in the dark

A massive tee was just one of hundreds toppled across western New York on Tuesday afternoon. (Syracuse.com)

A powerful line of thunderstorms and strong winds raced across Ontario, New York, Quebec and Vermont on Tuesday afternoon. The storms fueled by high heat and humidity, it reached 31C (88F) in Montreal, knocked down trees and power lines across a wide area. Thousands of homes went dark and remained that way for hours.

The carnage started in central and western New York early in the afternoon as significant damage from strong winds and isolated tornadoes was reported around Syracuse. In Madison County, NY, 4 people were killed after their homes were flattened by wind and thunderstorms. Power outages to over 250,000 homes and businesses were reported from Ohio and Pennsylvania into New York and Vermont by late afternoon. The front hit Montreal around 9pm Tuesday night with winds gusting between 70-90km/h across the entire metro region and Laval. Hydro Quebec reported over 100,000 customers in the dark across the province, 65,000 just in metro Montreal. Hard work overnight by the utility has dropped that number to 16,000 this morning.

Hydro Quebec was busy overnight restoring power to 100,000 Quebec homes and businesses. Between thunderstorms and tropical storm Arthur, the utility has had a crazy busy week. (CJAD)

Here on L'Ile Perrot around 12mm (0.5") of rain fell with the storms between 7 and 9pm, there was very little lightning, and winds over 50km/h. The front has broken the suffocating humidity, humidex readings were as high as 37C (100F) on Tuesday. Today will be cloudy with breaks, windy and cooler with highs near 24C (76F), and less humid. The heat and humidity will break until Saturday when it will begin to build again.

Warm & humid Tuesday for southern Quebec

Several times this summer it looked like Montreal was in line for strong to severe thunderstorms, but fortunately they have not materialized, at least in the city proper. Just this month alone there have been at least three days, including Monday, where the parameters and ingredients were right for thunderstorms. But like the previous two days, none developed on Monday in Montreal. The main area of thunderstorms once again moved across portions of Ontario and into central New York and southern Vermont. We did however have showers for a big portion of the day with a light rainfall of 5-10mm in most metro locations, just enough to water the lawn. There were some reports of 20-30mm closer to the US border and just across it in Vermont.

The warm front the caused the showers Monday is now well east of the region with Montreal in the warm sector. Temperatures are already in the middle 20's, look for warm, muggy highs of 29C (85F) today. A rather vigorous cold front will cross the region late this evening with showers and thunderstorms possible in Ontario, Quebec and New York from the supper hour to around midnight. Lows tonight will be around 20C (68F) with highs on Wednesday at 25C (77F). Some showers may linger into Wednesday but there will also be a few glimpses of sun.Thursday into the early portion of the weekend looks good with plenty of sunshine and seasonably warm. It will become more humid with thunderstorms by Sunday.

A photo of just some of the damage on the farm of Ray Derdall near Outlook, Saskatchewan. He also had major damage done to his home. (Star Phoenix)

SASKATCHEWAN TORNADOES
Environment Canada was out investigating the weekend tornadoes across Saskatchewan. Six tornadoes were reported between 2:30 and 4pm Saturday afternoon. The strongest occurred near Outlook, and was an estimated EF2 capable of winds between 178-217km/h. Major damage was reported on one farm near Outlook.


Meanwhile the cleanup continues in the Maritimes from Tropical Storm Arthur. There are still 65,000 homes and businesses without power in New Brunswick alone. It will take until the weekend to restore all customers.

In southern Manitoba major flooding continues along the Assiniboine River. Sandbagging efforts are well underway to try to alleviate some of the expected flooding in Brandon.

Strong thunderstorms possible for Montreal today - Arthur's aftermath

Above: I had friends visiting New Richmond on the Gaspe Coast this past weekend and they sent me photos of some of the tree damage from Arthur. Below: Hydro Quebec crews busy in the Gaspe restoring power to thousands. They will also send 40 crews to New Brunswick to help. (ValleyWX Photos)

  It was a very busy and wild weather weekend from coast to coast in Canada. Whether it was heat and humidity, fierce thunderstorms, strong winds or hurricane Arthur, we had a little bit of everything. Montreal remained on the western edge of Tropical Storm Arthur with high cloud cover and very gusty northwest winds. The winds across southern Quebec were in the 40-60km/h range most of the weekend. This resulted in scattered power outages across the region.

MONTREAL THUNDERSTORMS
Today we can expect a frontal boundary to slice into a humid air mass giving southern Quebec the possibility of strong thunderstorms. The main threat for Montreal would be from heavy rain and perhaps gusty winds up to 80km/h. The storms should begin by noon and last into the early evening. It will be warm and muggy with highs near 26C.

Fredericton, New Brunswick was hard hit by Arthur with numerous trees down and power out. (CBC News)

Tropical Storm Arthur
Arthur is now history this morning, dissipating over the far north Atlantic. The storm crossed the Nova Scotia coast early on Saturday morning with winds over 100km/h and heavy rain. While flooding and a small storm surge did occur, the big news was the wind. A peak gust to 139km/h (87mph) was reported in Greenwood, Nova Scotia, and winds well in excess of 100km/h occurred across a wide area of New Brunswick, P.E.I and eastern Quebec. Thousands of trees were toppled across Atlantic Canada and Quebec, many hitting homes and taking down power lines. The wind knocked power out to over 250,000 homes in Quebec and the Maritimes. Over 135,000 in New Brunswick alone making it the largest power outage in that provinces history. NB Power reports 155 crews restoring power with another 40 arriving from Hydro Quebec today. It may take until Thursday for all power to be fully restored.

Outlook, Saskatchewan tornado

Severe weather across the country this weekend from tropical storm Arthur on the east coast to tornadoes in Saskatchewan and Manitoba. The video above from The Weather Network shows a large tornado near Outlook, Saskatchewan.

Hurricane Arthur hits Atlantic Canada and the Gaspe

Flooding from Arthur in Yarmouth, Nova Scotia on Saturday morning. (CBC News)

The heavy rain and strong winds of now post topical storm Arthur are spreading across the Maritimes and eventually into Newfoundland this weekend. The western edge of the storm actually sent clouds into Montreal as well as gusty winds up to 50km/h from the broad circulation of the storm, but little else. The heavy rain and winds in excess of 100km/h are occurring across Nova Scotia, PEI and New Bruinswick as well as the Gaspe Coast. The center of what is left of once hurricane Arthur is currently located near the mouth of the Bay of Fundy, moving northeast at 23mph. Most of the heavy rain is occurring across Maine and New Brunswick this morning. Flooding has also been reported along the south coast of Nova Scotia. Yarmouth recorded a wind gust to 103km/h this morning, and nearly 150,000 homes are without power in the Maritimes. Several trees have already fallen onto homes with damage reported.

Rainfall will reach 100-150mm (4-6 inches) across portions of New Brunswick and the Gaspe/Lower North Shore of eastern Quebec today. Arthur will move into the Gulf of St Lawrence later this evening and into Newfoundland Sunday, slowly releasing its grip on Atlantic Canada.

On Friday Arthur pounded North Carolina before moving across the coastal waters of New England. Very heavy rain along the western edge of the tropical system along with a cold front produced nearly 200mm of rain in southeast Massachusetts. New Hampshire also had heavy rain and even a waterspout on Lake Winnepesaukee.

Arthur blasts the Outer Banks of North Carolina

Calm before Arthur: Mariners lock down boats in Nova Scotia prior to the arrival of Arthur. (CBC Nova Scotia)

The 120 mile long chain of barrier islands located off the North Carolina coast known as the Outer Banks, took a direct hit from Hurricane Arthur overnight. The low lying area is prone to flooding and that is what we are seeing this morning with water covering the only north south route, State Highway 12, under several feet of sand and water. Arthur made landfall last evening further south over mainland North Carolina near Beaufort Inlet and then crossed Hatteras Island back into the Atlantic Ocean. Peak winds across the Outer Banks were either side of 100mph overnight. The storm has since raced northeast at over 20mph and is now located off the coast in the Atlantic northeast of Kitty Hawk. Widespread power outages have also been reported but the very early assessment by emergency management has not reported any major damage or injuries so far with the exception of washed out roads. Hatteras and Ocarcoke Islands remain closed to visitors at this time. Rain and wind will slowly ease and seas subside today.

Winds whip waves across the Manteo/Nags Head Causeway in Eastern North Carolina Friday morning. The Outer Banks remain closed on this July 4th after Arthur pounded the region overnight. (13 News Now Weather)

Arthur will now move well off the Atlantic coast and brush Cape Cod before moving into Nova Scotia early Saturday morning. A tropical storm watch is in effect for coastal regions of Nova Scotia, New Brunswick and PEI. Rainfall of over 100mm, 100km/h winds and a storm surge can be expected starting late tonight and lasting into Saturday afternoon. Landfall of Arthur will likely occur near the Bay of Fundy early Saturday morning with the system crossing Nova Scotia and then heading into Newfoundland while weakening somewhat by Sunday. It will be a rainy, windy and wild weekend in Atlantic Canada.

Hurricane Arthur to impact Atlantic Canada

On Wednesday Montreal reached 30C again with the showers and thunderstorms remaining south of Montreal as expected. A few thunderstorms moved across the Ottawa Valley late last night but again they manged to miss metro Montreal. Today will be warm and humid once again but this should be the last day for this current spell. A cold front will introduce clouds and showers by the middle afternoon with perhaps some thunder. Temperatures will be cooler today at 27C (81F) due to precipitation and cloud cover. Showers tonight and early Friday with much cooler weather expected, lows near 17C and Friday highs around 22C, natural air conditioning.

The location of Hurricane Arthur at 5am Thursday, July 3, as well as the anticipated track northeast towards Nova Scotia by this upcoming weekend.

HURRICANE ARTHUR
The first named hurricane of the 2014 season is located about 340 miles southwest of Cape Hatteras, North Carolina this morning. NOAA Hurricane Hunters had the storm reaching hurricane strength (category 1) of 75mph this morning at 5AM. A strengthening of the storm is forecast and winds could reach 85-95mph today. The system is moving towards the north at 9mph. A hurricane warning is in effect for the North Carolina coast as far north as Virginia Beach. Mandatory evacuations started this morning along the Outer Banks of North Carolina, particularly Hatters and Ocracoke Islands. As I mentioned yesterday, I am very familiar with the geography of the Outer Banks and any type of storm is problematic for the low lying barrier islands. Airing on the side of caution, and on the eve of the 4th of July weekend, evacuations were ordered. The initial affects of the storm will be rising surf and wind late this afternoon. Up to 150mm (6 inches) of rain along with winds in excess of 100mph are possible by early Friday. In addition, a storm surge of  2-4 feet is possible with coastal flooding expected.

By late Friday and into the weekend the system will accelerate northeast towards Nova Scotia with landfall as a category 1 hurricane or strong tropical storm likely on Saturday very close to Halifax according to computer models. Heavy rain, strong winds and a storm surge are expected for portions of Nova Scotia, PEI and perhaps the Gulf of St. Lawrence in Quebec and New Brunswick. The details will be more refined and watches or warnings posted later today or early Friday.

Record high 33C for Montreal

A heat warning remains posted by Environment Canada for southwest Quebec as heat index values approach 37C (100F) once again this afternoon. Tuesday was the warmest Canada Day ever in Montreal as the mercury officially hit 33.2C (91.7F) at Trudeau Airport. The previous record was 32.5C from 1963. It remained warm overnight dropping only into the low 20's,  we are sitting at 26C (79F) already at 8am this morning. Temperatures will be a degree or two cooler today but remaining humid with highs near 31C (88F). The record today, also from 1963, is 34.4C.

The forecast for the most part was dry on Canada Day for Montreal with thunderstorms remaining over the Laurentians and Ottawa Valley or well south of Quebec in central New York. The storms were fast moving but did produce some wind damage across the lower Laurentians. Today's risk for storms is rather low for Montreal with the main dynamic south of the city across New York and Vermont and perhaps into the Sherbrooke area.It will remain hazy and humid in southern Quebec into Thursday with lows tonight near 22C and highs Thursday once again approaching 30C. A trough will bring showers and thunderstorms late Thursday with cooler and dryer weather arriving by late Friday. The weekend looks sunny with near normal temperatures.

A spectacular visible image of a strengthening tropical storm Arthur east of Florida this morning. Note the thunderstorm tops bubbling high into the atmosphere. (NOAA)

ARTHUR
Tropical storm Arthur developed as expected on Tuesday and now has 60mph winds. The deepening storm with impressive convection is located a few miles off the Florida coast about 495 miles south of Charleston, South Carolina, moving north at 6 mph. This morning tropical storm warnings are in affect along the Florida coast, with a hurricane watch posted along the fragile North Carolina coast including the Outer Banks south of Oregon Inlet. Arthur is forecast to intensify into a minimal hurricane while approaching North Carolina by Friday. Heavy rain and high surf will be the primary threat at this time. I have vacationed on Hatteras Island since 1991 and this region is highly vulnerable to flooding from both the ocean and sound. Beyond the Carolina's the storm could bring high winds and rain to Nova Scotia and PEI by this weekend.

Warmest day of 2014 for Montreal - strong storms likely

Happy Canada Day.

We are warm and very humid this morning in Montreal as temperatures start the day in the mid 20's. Currently I have 25C on L'Ile Perrot but with an 83 per cent humidity, it feels quite uncomfortable. A heat warning is in effect for eastern Ontario and southwest Quebec. Temperatures will warm under hazy sunshine to 33C (92F) today with heat index values close to 38C (100F) for metro Montreal and the surrounding region. As always try to limit extreme outdoor activities and drink plenty of water. Temperatures will remain warm tonight, dropping to 23C and warm again on Wednesday at 30C. It should turn cooler and less humid by Thursday.

SEVERE THUNDERSTORMS
The other threat today will come in the form of strong thunderstorms. A cold front moving into Ontario and Quebec will trigger these storms, and with plenty of moisture and energy available they could be quite strong. The threat will begin early this afternoon in western Quebec and Ontario, and spread towards metro Montreal by the supper hour. Already this morning a severe thunderstorm watch has been posted north and west of Montreal. With today being a holiday and many outdoor activities scheduled, it is important to be aware of any potential severe weather and warnings that may be issued later today for Montreal. The main threat will be strong winds and possible hail. There is also the risk of an isolated tornado in regions northwest of Montreal and across southern Ontario.

The current forecast track of Arthur may take it towards Nova Scotia by the weekend. (NHC)

Tropical Storm Arthur
Forecasters at the National Hurricane Center in Florida are tracking the first tropical system of the young 2014 season in the Atlantic basin. Depression one will likely become tropical storm Arthur today as winds reach 39mph. The storm is forecast to slowly develop just off the US southeast coast. It is forecast at this time to remain just offshore with heavy rain (3-5 inches) and rough surf expected on the coast from northeast Florida to North Carolina. The potential is there for Arthur to become a hurricane by the weekend near the Outer Banks. We will have to watch this system closely as the potential is there for some weather to affect Atlantic Canada by the weekend. At this time the New England beaches look to be spared from a direct hit, however the surf will be rough.