Wednesday, September 30, 2015

Major east coast rain as Joaquin forms in Atlantic

A poorly timed cold front produced heavy rain and snarled traffic during the Tuesday evening commute in Montreal. (ValleyWX)
 Tuesday was very warm across southern Quebec, perhaps the last really muggy day of 2015. Temperatures reached 25C (77F) in Montreal, well above the normal high of 17C (63F). A cold front plowed into the St. Lawrence Valley during the evening commute with very heavy rain. Nearly 20mm fell in less than one hour in Montreal, with 35mm as of 7am this morning. As much as 51mm fell in Kemptville, Ontario with the frontal passage. Light rain continues in Montreal this morning, but the heavy rain has settled south along the US border and into New England. The front has stalled over those regions and is acting like a conveyor transporting copious amounts of tropical moisture into the northeast. Rainfall may exceed 100mm (4 inches) from Pennsylvania and New York into southern New England and the Maritimes. Numerous flood watches and warnings are on place including heavy rain warnings for the Eastern Townships. High pressure will slowly clear out southern Quebec over the next 24 hours, but it will be much cooler along with stiff northwest winds up to 50km/h. Low temperatures in Montreal will drop to 5C (41F) with highs around 14C (56F).

The current NHC forecast track for Joaquin.
Tropical Storm Joaquin
Another major player in the flood potential shaping up along the east coast will be the future track of tropical storm Joaquin. The storm developed in the Atlantic this week and is located 240 miles east northeast of the Bahamas this morning. Joaquin has 70 mph winds but is strengthening and will likely reach hurricane status today. Joaquin is expected to drift west southwest over the next 24 hours before moving north. The storm may impact portions of the eastern US and Canada beginning as early as Sunday with torrential rain. One forecast model has the storm approaching northern New England and southern Quebec by late Monday. Another has it remaining over the Atlantic. This storm will have to be monitored very closely, especially for coastal regions from North Carolina to Nova Scotia. The National Hurricane Center forecast models have Joaquin reaching Category 2 strength with winds in excess of 100mph. With most of the area from the middle Atlantic north being saturated with the current rain event, the potential for major flooding is very real.

Monday, September 28, 2015

A more fall like weather pattern for Montreal

A ship passes under the full harvest moon around 7pm along the St. Lawrence Seaway off L'Ile Perrot. (ValleyWX)
The lunar eclipse begins shortly after 8pm last evening. This photo was taken from L'Ile Perrot. (ValleyWX)
It was a beautiful night to watch the rising of the harvest moon and the total lunar eclipse on Sunday evening. The celestial event, 30 years in the making, did not dissapoint. I went to Pointe-du-Moulin on the tip of L'Ile Perrot and took the photos you see above and below. I was using my old reliable Canon Power Shot 35mm Digital with the zoom maxed out. It was a perfect night, warm temperatures for late September and just a light breeze lapping the waves against the shore, simply stunning.

The lunar eclipse reaches totality just after 10pm last evening. This photo was taken from L'Ile Perrot. (ValleyWX)
After what was basically an extension of summer during the month of September in Montreal, we are looking at a more seasonable weather pattern over the next few days. Monday and Tuesday will be cloudy with scattered showers and warm temperatures near 23C (73F). By late Tuesday a cold front will cross the region and tap into moisture moving up the east coast. Expect steady rain to develop by late in the day Tuesday and continue overnight. Amounts may exceed 25mm over Ontario, Quebec and New England. Skies will slowly clear Wednesday but it will turn much cooler with highs only in the middle teens. Temperatures will average below normal to end the week with even a risk of frost on a couple of nights as lows fall into the 2 to 4C (36-40F) range. More rain and cooler weather is possible to end the week. We may have just seen the last of the really warm air until next spring.

Sunday, September 27, 2015

Lunar Eclipse Update
Excellent fall weather continues for much of southern Quebec this weekend. Temperatures have trended a touch cooler, especially the overnight lows. We start the morning at a chilly 5C (41F) here on L'Ile Perrot with just a hint of frost on some roof tops. Some rural areas in eastern Ontario and southern Quebec were as low as 1C (33F) with a light ground frost. It will warm rapidly today under a light southerly flow with high temperatures near 24C (76F). This will be the last really warm day for quite some time as cooler weather and showers are forecast this week.

Tonight is the big super harvest moon (see story below). The largest and closest full moon of the year, will rise in Montreal at 6:36pm. The eclipse will begin around 8:45pm, reaching totality near 10:30pm. The weather looks perfect here in Montreal with clouds remaining to our south and west. Nothing but clear skies are expected, at least until midnight, when clouds will begin to increase.

Huge waves pound coastal highway 12 in Kitty Hawk, North Carolina. (OBX Voice)
Those clouds are part of a large coastal storm that has been moving up the eastern seaboard. The system has brought heavy rain, high winds and round after round of high tides and coastal flooding from the Carolinas north. The combination of the supermoon and this storm are flooding portions of the Outer Banks of North Carolina. Tides can run as much as 30 percent above normal during a supermoon. Those tides along with the storm are pushing the Atlantic Ocean over the dunes and flooding portions of State Highway 12. Flooding has also been reported in South Carolina and along the coast northward into New Jersey.

Wednesday, September 23, 2015

Fall equinox, harvest supermoon plus a lunar eclipse

A stunning photo of the full supermoon from October 2014
What a celestial week it will be across North America. First, fall arrived in the Northern Hemisphere at 4:21 AM eastern time this morning. We have been greeted with another spectacular day to start the new season with the mercury pushing 25C (77F) this afternoon. It will be sunny all week and into the weekend as our record breaking September continues to unfold. When all is said and done this may turn out to be the warmest and brightest September ever for Montreal.

That brings us to another spectacular and rare event that is set to take place this weekend. A full lunar eclipse will occur during the evening of Sunday, September 27th, visible across North and South America, Europe and Africa. It will occur with the moon in perigee, or the closest to Earth on its orbit during the entire year. This is known as a supermoon and this year it will coincide with the full harvest moon as well. The harvest moon is the first full moon that occurs after the Autumnal Equinox. It is already known as a big and bright moon, but this year it is expected to be 15 to 30 percent brighter depending on your location.

Only 5 times in recent history has this type if an event occurred with all the above mentioned factors in line; 1910, 1928, 1946, 1964 and 1982. The full harvest moon will rise at 6:42pm in Montreal Sunday night,  and will begin to dim at 8:11pm. The lunar eclipse will reach totality at 10:11pm. A lunar eclipse is safe to watch, so grab your camera and find a dark location, preferably away from the city lights.

Monday, September 21, 2015

Beautiful end to summer 2015

A perfect end to summer is expected across southern Quebec, Ontario and New England.
Ontario, Quebec and New England will have a spectacular end to the summer and start to fall 2015. The warm and muggy air of last week was replaced by a cooler more seasonable airmass on Sunday after the passage of a cold front Saturday night. That front bought a modest amount of rainfall with as much as 12mm (0.5 inches) reported in southern Quebec. Isolated thunderstorms accompanied the front in Montreal Saturday evening, but no severe weather was reported. Strong high pressure is now in control of the weather with nothing but sunshine and warm temperatures all week. Across the entire region, expect highs in the 21 to 24C (70-75F) range with overnight lows from 5 to 9C (40-50F). The longer nights mean we may see some morning dew and fog around locally. This morning temperatures are the coolest they have been since last spring, L'Ile Perrot is at 6.7C (44F), while St. Anicet is only 3C (39F).

Looking ahead we have a rather spectacular celestial event on the night of September 27th. The full harvest moon will also be a "supermoon" and go through a total lunar eclipse. I will have much more on that later this week.

Thursday, September 17, 2015

Perfect late summer weather to continue for Montreal

This NOAA water vapor image clearly shows the ridge of high pressure over the northeast US that is responsible for our perfect late summer weather. Sunshine and well above normal temperatures will prevail into Saturday for Montreal, while the clouds and rain remain well to our north and across the southeast US coast..
 Montreal is well on its way to another record high today as the temperature has already surpassed the long term average for the date, and it is only 10am. Montreal is currently 23C (73F) with a forecast high of 29C (85F) expected under sunny skies. The record high for today established in 1942 is 28.9C.

On Wednesday the temperature reached 28C (83F) at Trudeau Airport breaking the previous record of 26.8C (80F) set in 1991. The normal high for this time of year is 19C (66F). Strong high pressure centered along the Atlantic coast is responsible for the perfect late summer weather, and it will remain in place through Saturday. Late Saturday a cold front will bring some rain that will last into Sunday. Sunday will be cooler at 20C, but still above normal. Looking ahead to next week, sunshine and warm weather will return once again as we welcome Autumn on September 23rd. Temperatures will again reach the middle 20's. No cold air in in sight through the end of the month and even into early October for southern Quebec.

Monday, September 14, 2015

Warm weather returns this week to Quebec & Ontario

It was a wet and at times stormy weekend in Montreal as a rather strong early fall storm system swept across the Great Lakes. It remains over northern New England this morning, slowly moving northeast away from the region. The system brought as much as 50mm of rain to parts of Quebec including 34.2mm here on L'Ile Perrot, 44mm to Trudeau Airport and 48mm at St Jovite. The rain was accompanied by cooler temperatures. A few breaks in the cloud cover Sunday afternoon in Montreal set up some isolated thunderstorms. A few were strong with heavy rain and plenty of lightning.

The system in question will slowly move away from Quebec today with showers expected this morning, slowly tapering off this afternoon. It will be another cool day with breezy conditions and high near 20C (68F). The good news for those who are not ready to say goodbye to summer, is we are in for a great stretch of weather. The last official week of summer 2015 will feature wall to wall sunshine with temperatures well above normal. Starting Tuesday highs will be in the middle 20's (77-80F) approcing 30C (86F) by Friday. Lows will be around 14C (57F). Scattered fog is possible in the pre-dawn hours each night.

Fire to flood: Wildfires are raging across portions of western North America and particularly in California. The fires have destroyed thousands of acres of land and hundreds of homes. California has been hot and bone dry for months. It is expected that the strengthening El Nino will bring widespread winter storms and heavy rain to the same region by the start of 2016. (AP Photo)

While the weather was wet in the east this weekend, it remains bone dry across portions of California and the west. Wildfires have spread across five states including hard hit California. Numerous homes were destroyed as thousands of firefighters battle the blazes.

Friday, September 11, 2015

Cool wet weather arrives for the weekend

A cool, wet weekend is forecast for southern Quebec and New England.
 After record high temperatures and a very pleasant start to September, Montreal and portions of Ontario, Quebec and New England are in for a fall preview. A rather potent area of low pressure is forecast to develop today across the southern Appalachians and deepen as it moves northeast into New England. The system will bring an area of rain to Montreal along with cooler temperatures by late Saturday.

Friday will be a nearly perfect day with abundant sunshine and temperatures near 24C (76F). It will remain clear overnight with a low of 12C (54F). On Saturday clouds will increase from south to north with rain developing in the evening. It will be a little cooler with a high near 22C (72F). Saturday night and Sunday the rain will cover the entire region with perhaps over 25mm falling. Cooler temperatures will also prevail with lows in the middle teens and highs Sunday no better than 19C (66F). The start of next week will remain unsettled and cool before we see a return to sunshine and above normal temperatures by Wednesday into Friday.

Heavy rain along the US east coast produced flash flooding. The picture above is from Staten Island, New York on Thursday, September 10. (AccuWeather)

Early this morning heavy rain continues to fall across eastern New England and Atlantic Canada in response to low pressure located near New York City. This storm did not affect southwest Quebec, but did produce record rainfall from Philadelphia to New York City on Thursday. Anywhere from 1 to 4 inches of rain occurred (25-100mm) producing flash flooding in many locations and establishing numerous one day record rainfall totals. Those included Philadelphia with 4.76 inches and JFK in New York City with 1.18 inches.

Tuesday, September 08, 2015

September heatwave almost over for Montreal

Lightning illuminates the sky over L'Ile Perrot late last evening. The storms produced heavy rain and strong winds and provided some relief from a sultry day. (ValleyWeather Photo)
 That was one of the warmest Labour Day Weekends across southern Quebec and Ontario in quite some time. Montreal flirted with record highs both Sunday and Monday as the mercury hit 31C (88F) and 32C (90F) respectively, missing the record high by tenths of a degree. Other parts of the region were as warm as 34C (94F) and I recorded the second warmest day of the summer on L'Ile Perrot as the temperature hit 33C (91F) on Monday. The hot weather was accompanied by high humidity which helped to push the humidex value to 41C (106F) in Montreal Monday afternoon. These temperatures are well above the normal high for early September of 21C (70F). Even the overnight lows have remained warm in the low 20's in Montreal.

It was a spectacular Labour Day holiday to cruise the canal and boardwalk in Sainte-Anne-de-Bellevue. What a way to end the summer. (ValleyWeather Photo)
It was back to school and work Tuesday heralding the end of another summer. Despite that, it was another warm and very humid day reaching 28C (83F) so far this afternoon. It will remain warm and muggy overnight with lows remaining in the low 20's. Wednesday should be the last day of this heatwave as we are forecasting a cold front to arrive in southern Quebec late in the day. Hazy sunshine will give way to some welcome showers and thunderstorms with a high of 30C (86F).

Last night some air mass thunderstorms produced severe weather from eastern Ontario across metro Montreal. The storms prompted a tornado warning from Winchester, Ontario south into the Seaway Valley. In Montreal vivid lightning, strong gusty winds and torrential rain swept the region around 10pm. The storm deposited the first rainfall of September at my home on L'Ile Perrot where 18mm fell in under 30 minutes. Winds gusted up to 110km/h with the storms knocking out power to over 23,000 hydro Quebec customers. Those affected were mainly in the Lanuadiere region, but 5000 were affected in metro Montreal as well.

Friday, September 04, 2015

Spectacular Labour Day weekend weather

Summer 2015 is ending on a high note across much of Eastern Canada and the northeast US. Sunshine and much above normal temperatures are forecast across the entire region.

A weak backdoor cold front brought in a little cooler and dryer air overnight in Montreal. No precipitation fell in the city and we have had none so far this month. After a 28C (84F) high on Thursday we dropped to 14C (58F) this morning. High pressure will re-establish itself along the Eastern Seaboard into the upcoming holiday weekend with nothing but sunshine forecast through Sunday. Temperatures will rise from a high of 25C (77F) today to as warm as 32C (90F) on Monday, which is well above normal for early September. The normal high in Montreal is 22C (72F). The threat for precipitation will increase by late Monday in the form of showers and thunderstorms as a frontal boundary crosses the Great Lakes. The weather will remain very warm and humid into Tuesday before we see any appreciable cooling.

Incidentally despite the warm weather, the leaves are rapidly changing colour and in some cases even falling off the trees. As we have learned in the past, cooler weather and frost accelerates this process but it is the change in daylight that actually generates it and moves the colour along. The leaves would change colour even if is stayed hot into October.

Wednesday, September 02, 2015

Summer warmth well into September for Montreal

A spectacular rainbow over Montreal late last week. Summery weather is forecast for at least the next week. (ValleyWeather)
Welcome to meteorological fall. I love September, in recent years the month has been a perfect mix of summer warmth, but with cooler nights for sleeping. It was not always that way for me, as a child it meant going back to school, and I loved summer too much. It seems that back when I was younger the start of September almost always introduced cooler fall weather. But in recent years, whether through global warming or other factors, September has become an extension of summer.

That brings us to September 2015 and an incredible spell of weather. High pressure is forecast to dominate the weather right through the upcoming Labor Day weekend. Each morning begins the same way with low clouds and fog developing. This is a result of the humid air and longer nights. Once the clouds burn off we can expect sunshine. The sunny weather will last into the weekend. The only glitch will be a weak backdoor cold front overnight tonight that will bring the threat for showers and thunderstorms. Thursday and Friday will be a touch cooler and less humid. High temperatures through the next week will range in the middle to upper 20's with lows in the upper teens. The extended forecast is showing a very warm September with above normal temperatures and below normal precipitation for southern Quebec.