Winter Roars Into Ontario This Week With Freezing Rain Threat; Snow Squalls Could Dump Up to 50cm of Snow

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While winter has gotten off to a slow start across Southern Ontario, with many areas only seeing their first snowfall within the past week or two, it seems that change is on the way. November is shaping up to go out like a lion, as Mother Nature makes up for lost time.

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A significant pattern shift is expected to bring the threat of freezing rain late Monday across Central and Eastern Ontario. This will be followed by multiple weaker systems across the Great Lakes region and colder air flooding into the province.

That colder air will set the stage for what could become our first major snow squall event later this week and into the weekend. In some typical snowbelt areas, snowfall could be measured in feet (30+ cm) by this time next week!

Let’s break down what is shaping up to be a very dynamic and active forecast over the next five to seven days, starting with the freezing rain threat.

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Freezing Rain Risk: Monday into Tuesday

PRECIPITATION TYPE - MAP FROM WEATHERBELL

A system is expected to move into Southwestern Ontario and the Golden Horseshoe beginning Monday afternoon. With temperatures forecasted to stay well above freezing in these areas, precipitation will fall as rain.

However, as the system moves northeast into Central and Eastern Ontario after midnight, it will encounter a stubborn layer of colder air near the surface. Temperatures hovering near or just below freezing may allow some of the rain to fall as freezing rain overnight into early Tuesday morning.

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There remains some uncertainty about how widespread this pocket of cold air will be. Higher-elevation areas of Central and Eastern Ontario, including Bancroft, Barry’s Bay, and Algonquin Park, are most likely to experience freezing rain. It’s also possible for freezing rain to extend westward to Muskoka and Parry Sound, and eastward into the Ottawa Valley, including the City of Ottawa.

For Bancroft, Barry’s Bay, and Algonquin Park, ice accretion totals could reach 2-4 mm by Tuesday morning, though any ice will quickly melt after sunrise as temperatures rise above freezing by late morning. In Muskoka and the Ottawa Valley, a thin layer of ice on untreated surfaces is possible, which could make for a slow Tuesday morning commute. There is a slight chance of school bus cancellations in affected areas.

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Northern Ontario: Heavy Snowfall Ahead

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Northern Ontario will experience heavy snow from this same system, as colder air dominates in the region. Light to moderate snowfall is expected to begin in Northwestern Ontario by early Monday afternoon, gradually spreading eastward into the evening and overnight.

Snow will continue across Northern Ontario throughout Tuesday, with the heaviest snowfall expected near the Quebec border in Northeastern Ontario. Snowfall will gradually ease later on Tuesday and into early Wednesday but could persist near James Bay in a zone extending from Hearst to Lansdowne House.

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Over three days, snowfall totals will generally range from 10 to 20 cm across Northern Ontario. Far Northern Ontario near James Bay could see totals exceeding 20 cm by Thursday, while lake-enhanced snowfall southeast of Lake Superior, including Sault Ste. Marie, could push totals closer to 30 cm.

Thunder Bay is expected to see slightly less snow, as the city may end up in a drier part of the system. Forecasts currently suggest snowfall amounts of 5 to 10 cm in this area.

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Southern Ontario: Cold Air and Lake Effect Snow

PRECIPITATION TYPE - MAP FROM WEATHERBELL

As the system moves out of Southern Ontario late Tuesday, a surge of cold air will follow in its wake. This will briefly activate the lake effect snow machine around Lake Huron and Georgian Bay beginning Tuesday evening and lasting into Wednesday.

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At this time, temperatures are expected to hover near the freezing mark, which could limit significant accumulation. The most likely target zone for this initial burst of lake effect snow includes areas east of Georgian Bay, such as Parry Sound, Huntsville, and Bracebridge. These areas could see 10-15 cm, with localized amounts of up to 20 cm by the time snow bands taper off Wednesday evening.

For higher elevations southeast of Owen Sound, including Hanover, Markdale, Shelburne, and Orangeville, up to 5-10 cm of snow is possible, as cooler temperatures in these areas will allow snow to accumulate more easily. Surrounding regions, including parts of the Greater Toronto Area, may see just a few light flurries.

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End of the Week: A Snow Squall Event Looms

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Lake effect snow will temporarily pause as another system slides through the Great Lakes region. However, this system appears to stay largely south of the border, bringing only a few flurries or light showers to areas near Lake Erie and the Golden Horseshoe early Thursday.

As we approach the weekend, Southern Ontario will see its coldest air of the season so far, with overnight lows plunging to several degrees below freezing across much of the province.

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A dominant westerly to northwesterly wind is expected to develop Friday and persist into the weekend. This setup will create ideal conditions for intense snow squalls off Lake Huron, Lake Superior, and Georgian Bay starting Friday afternoon and lasting through the weekend.

These snow squalls could bring significant snowfall totals, blowing snow, and near-zero visibility to localized areas in the snowbelt. Travel could become difficult or even dangerous in the hardest-hit regions.

Based on the current forecasted wind direction, regions including Kincardine, Owen Sound, Hanover, Midland, Oro, Orillia, and Gravenhurst are likely to see the heaviest impacts. This also extends up into Northern Ontario around the Lake Superior shoreline with Sault Ste. Marie in the bullseye. Some locations within this zone could receive up to 50 cm of snow by the end of the weekend.

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Snow Squall Uncertainty

It’s important to note that snow squalls are highly localized events, and not everyone will experience intense snowfall totals. One area may receive significant snow accumulations, while locations just a few kilometres away might see only a dusting.

Confidence is high that some sort of snow squall event will occur, but exact locations will depend on the finer details of wind direction and temperatures.

CREDIT: Environment CANADA

Environment Canada has also mentioned the potential for significant snow squalls later this week:

The first significant lake effect snow of the season is likely beginning Friday. This has the potential to be a highly disruptive and prolonged event for areas near Lake Huron, Georgian Bay and eastern Lake Superior. While confidence is medium to high that lake effect snow and blowing snow will occur, confidence in exact locations to be affected as well as snowfall accumulations is low. As is normally the case in these situations, snowfall amounts will be highly variable. Some areas may see well in excess of 50 cm by the end of the weekend. - Environment Canada

Stay tuned for updated forecasts in the coming days as higher-resolution models provide more details. We’ll refine the snow squall forecast and pinpoint areas most at risk.

Season’s First Snowfall Possible for Wide Swath of Southern Ontario Starting Late Wednesday

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Over the past week, calm conditions have dominated the weather story across Southern Ontario. This pattern has also brought a return to more seasonal temperatures typical for this time of year, a noticeable shift from the unseasonably warm weather that lingered into early November.

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One notable absence so far this season is snow—a staple of November in Southern Ontario. While some regions, especially higher elevations in Central Ontario, the Ottawa Valley, and the Dundalk Highlands, experienced their first flurries as early as September and October, much of Southern Ontario has yet to see its first snowfall.

That, however, could soon change with the arrival of multiple weather systems in the coming days, bringing colder air and the potential for wet flurries as early as Wednesday evening and into Thursday and Friday.

The good news for those not yet ready to embrace winter is that significant accumulation isn’t expected with this initial blast of wintry weather. Temperatures are forecast to hover just above freezing, which will likely limit accumulation as any snow melts upon contact with the wet and relatively warm ground left behind by earlier rainfall.

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In addition to the season’s first flurries, a slow-moving system will stall over the Great Lakes region, pulling in moisture from another system over New England. This setup will lead to ample precipitation, with heavy rain expected to persist into the start of the weekend. Eastern Ontario is poised to bear the brunt of this rainfall, with totals ranging from 25 to 50 mm between Wednesday and Saturday.

SIMULATED RADAR - MAP FROM WEATHERBELL

The rain is expected to begin on Wednesday afternoon, with the initial band of heavy rain arriving in Deep Southwestern Ontario and areas near the Lake Erie shoreline by dinnertime.

This line of precipitation may also bring embedded, non-severe thunderstorms and wind gusts of 70-80 km/h. While most gusts are expected to remain below the severe threshold, isolated gusts near 90 km/h are possible, particularly over the Niagara region during the early evening hours.

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PRECIPITATION TYPE - MAP FROM WEATHERBELL

As this line of rain races across Southwestern Ontario and into the Golden Horseshoe, colder air will begin rushing in from the west. However, there is some disagreement among models regarding how quickly temperatures will drop and how rapidly the precipitation will move. Some projections suggest a sharp cooldown, with temperatures in Southwestern Ontario nearing freezing by Wednesday evening.

If this happens, rain could transition to wet snow in areas such as Sarnia, London, Goderich, Kitchener, Guelph, and Orangeville. However, with earlier rainfall and temperatures still above freezing, any snow is likely to melt on contact. Elevated areas northwest of the GTA, particularly the Dundalk Highlands, may see light accumulation of up to 2-4 cm overnight into Thursday morning.

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PRECIPITATION TYPE - MAP FROM WEATHERBELL

By Thursday morning, most of the moisture will shift into Central and Eastern Ontario, with the centre of the low-pressure system stalled over Lake Huron. Meanwhile, a secondary system over New England will provide additional moisture, enhancing precipitation over Eastern Ontario throughout the day.

Temperatures in parts of Eastern Ontario, particularly southwest of Ottawa and in higher elevations, will hover near the freezing mark, creating a chance for wet flurries. Closer to the international border extending into the Ottawa region, heavy rain will likely continue.

Precipitation is expected to persist overnight Thursday and linger into Friday, with the heaviest rain focused on Eastern Ontario. In Central and Southwestern Ontario, lingering showers are possible Friday morning and afternoon, though they won’t be as intense as in the east.

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For rainfall totals, Eastern Ontario, including Kingston and Ottawa, can expect 25 to 50 mm by Saturday. The rest of Southern Ontario will likely see 10 to 25 mm, though isolated pockets could receive closer to 30-40 mm during thunderstorm activity.

Higher elevations in Eastern Ontario, particularly near Bancroft, may see persistent snow showers that could result in minor accumulation of up to 2-5 cm by Friday morning. However, with temperatures so close to freezing, it’s uncertain how much snow will stick.

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Looking ahead to the weekend, there’s good news for those not ready for snow. Earlier model predictions suggested a significant cooldown that could trigger lake-effect snow. However, the latest data indicates the cooldown won’t be as intense as initially thought.

While some lake-effect showers are still possible along the Lake Huron shoreline and southeast of Georgian Bay on Saturday, it likely won’t be cold enough for those showers to fall as snow.

What's in a Name? Choosing the Right Tires to Drive you Through Canadian Winters

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Tread patterns of summer, all season and winter tires. Image courtesy of discount tire.

Now that it’s the first week of November, many Canadians are starting to think about putting winter tires on their vehicles. There have been pockets of unseasonable warmth across the country in October and the start of November, the inevitable chill of winter is in the air, and many have already seen snow fall.

While winter tires are recommended throughout the country, they are mandatory in Quebec from December 1st to March 15th, and from October 1st to April 30th on certain British Columbia highways. Additionally, studded tires are allowed almost nationwide, with the exception of residents of Southern Ontario.

Insurance companies across the country offer discounts for installing winter tires as an incentive to encourage drivers to reduce the risk of accidents. So what makes winter tires that much better in the cold and snow than summer tires and where do all season and all weather tires fit into the mix?

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With the right tools, it can be pretty easy to change your own tires!

Summer Tires

Summer tires are designed to handle both wet and dry road conditions with their wide tread and soft rubber. These tires also usually have deeper grooves that improve traction on wet roads and reduce hydroplaning, making them ideal for the wet spring and summer months.

Winter Tires

Like their name suggests, winter tires have been designed for winter roads. They are made with rubber that stays flexible at temperatures below 7°C (45°F), the magic number at which other tires become stiff and lose traction, greatly reducing their performance. Furthermore, winter tires have different tread patterns that are meant to divert water and slush to the sides, as well as little slits called sipes that increase the overall grip of the tires and helping them maintain contact with icy road surfaces. Over the past several years, tire manufacturers have started to include additional small particles, like crushed glass or walnut shells, that act as little studs on the surface of the tire for extra grip.

Performance of All Season Tires vs Winter Tires with decreasing temperatures. Image courtesy of Discount Tire.

All Season & All Weather Tires

Some people argue that winter tires aren’t necessary if they have all season tires on their vehicle. Unfortunately, this is a slight misnomer because while these tires can handle a bit of cold and snow, they fail to handle heavier snowfalls that are common in Canadian winters. All season tires, unfortunately, sacrifice traction in wet conditions that would be found in summer tires and some of the flexibility and grip seen with winter tires in order for the tread to last longer. Realistically, these should be called 3 season tires as opposed to all season. So while they’re not the best option for winter driving in Canada, all season tires are definitely a better choice than regular summer tires.

All weather tires, not to be confused with all season tires, are a true year-round tire designed to handle Canadian winters. Unlike all season tires, these tires remain soft and flexible well below 7°C. The tread pattern on all weather tires is a combination of all season and winter tires, making them better suited for driving through heavier snow than all season tires. While they still don’t match the performance of a true winter tire, all weather tires are the best option for those who don’t want the hassle of swapping out their tires twice per year or simply do not have the space to store an extra set. Their versatility truly makes all weather tires a middle of the road tire (pun intended) for Canadian drivers.

The three-peak mountain snowflake symbol found on winter and all weather tires. Image courtesy of Canadian tire.

When looking for tires to get you through the winter, it is recommended to chose either a proper winter tire or an all weather tire, so long as it has the three-peak mountain and snowflake symbol on the sidewall. This is an industry standard symbol which indicates that the tire meets strict regulations for winter performance; becoming mandatory on all winter tires beginning in 2018, transitioning away from just using the M+S (Mud and Snow) designation.

Further Reading

https://www.canadiantire.ca/en/how-to/automotive/how-to-choose-winter-tires.html

https://www.continental-tires.com/ca/en/tire-knowledge/winter-tire-laws-in-canada/

https://www.continental-tires.com/ca/en/tire-knowledge/winter-tire-markings/

https://www.discounttire.com/learn/tires-below-45

https://www.discounttire.com/learn/winter-summer-allseason

Note: The author formerly received payments from “Big Tire” however, this article was not funded.

Trick-or-Treat: A Potential Spooky ‘Headless’ Comet Could Be Visible Across Canada Around Halloween

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It's been a spectacular year for skywatchers across Canada, with events like solar eclipses, supermoons, and vibrant northern lights lighting up the night. Now, it looks like we might be in for another treat—a "headless" comet could make an appearance just in time for Halloween.

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October seems to be the month of comets, with Comet Tsuchinshan-ATLAS gracing the early evening skies recently. Many stargazers caught glimpses of the comet, which was visible in the western sky just after sunset. Although it has since faded from naked-eye visibility, you can still catch it with a telescope, and it will remain somewhat visible into early November.

But the cosmic show isn’t over yet. A second comet, called Comet ATLAS (C/2024 S1), may arrive just in time for Halloween, and it comes with a spooky twist—it could appear "headless." The comet’s name might sound familiar because it was discovered by the same ATLAS asteroid tracking system, known for spotting objects that could potentially impact Earth.

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The main difference between this upcoming comet and the earlier one lies in its path. While the first comet passed safely between Earth and the Sun, around 40 million miles from the Sun, this new comet will come much closer, potentially within 700,000 miles of the Sun's surface. Because of this close approach, scientists predict that the comet’s head—its bright core—might disintegrate due to the Sun's intense heat, leaving just a faint, trailing tail visible from Earth.

To understand what makes a comet appear "headless," it's important to know a bit about its structure. Comets are made up of a nucleus, or core, composed of rock, dust, and frozen gases. When they approach the Sun, the heat causes the frozen gases to vaporize, forming a glowing coma around the nucleus and a tail that extends away from the Sun. If the nucleus disintegrates, the glowing head might vanish, leaving behind only a ghostly tail, hence the term "headless comet."

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ESTIMATED BRIGHTNESS OF COMET - SOURCE: sKYWALK.SPACE

The exact visibility of this comet remains uncertain. It will come closest to Earth on October 24th as it travels toward the Sun, reaching its closest point to the Sun, known as perihelion, on October 28th. There’s even a chance it could be bright enough to see during the day, potentially appearing as bright as Venus from 7:12 AM to 8:06 AM (ET) in the east-southeastern sky.

However, those in the Northern Hemisphere may struggle to spot it due to its position low in the sky near the Sun, making it difficult to see without obstruction from sunlight or clouds.

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NASA offers some tips for spotting the comet during this close approach. To view it safely, you should block the Sun with an object such as a building or tree, then scan the lower left of the Sun's position in the sky. Be cautious and never use binoculars or telescopes, as accidentally focusing on the Sun can cause serious eye damage.

If the comet survives its close encounter with the Sun, it could become visible in the night sky around Halloween. This would provide skywatchers with a unique opportunity to see a potentially "headless" comet, with a long, wispy tail but no visible nucleus. The darkness of the moonless night sky could offer ideal conditions for observing this unusual celestial visitor, making it a fitting cosmic event for the spooky season.

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There is always the possibility that the comet disintegrates completely, leaving nothing visible to the naked eye. But if it endures, it will gradually fade after November 1st, requiring binoculars or a telescope for further observation. Unlike earlier this month, when a supermoon washed out the sky, the absence of a full moon could make for an even more impressive show, assuming the comet survives.

Stay tuned for updates as we keep an eye on this intriguing comet.

Why the Northern Lights Are Appearing More Frequently: NASA and NOAA Confirm Solar Maximum

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Visible light images from NASA’s Solar Dynamics Observatory highlight the appearance of the Sun at solar minimum (left, Dec. 2019) versus solar maximum (right, August 2024). During solar minimum, the Sun is often spotless. Sunspots are associated with solar activity, and are used to track solar cycle progress. Credit: NASA/SDO

During a recent teleconference, experts from NASA, NOAA, and the International Solar Cycle Prediction Panel confirmed that the Sun has entered its solar maximum, a period of heightened solar activity expected to last through the next year.

The solar cycle reaches this peak roughly every 11 years, during which the Sun shifts from a relatively calm state to a much more active phase characterized by increased magnetic activity and a higher number of sunspots. These sunspots, which are cooler areas on the Sun’s surface caused by intense magnetic fields, can trigger powerful solar eruptions that significantly impact space weather.

This surge in solar activity doesn’t just make for an interesting spectacle; it can also have practical consequences on Earth. Solar flares and eruptions during this time can interfere with communications, disrupt GPS signals, and even affect power grids. They can also pose potential hazards to satellites and astronauts in orbit.

But for skywatchers, there is an upside: the solar maximum period also brings more frequent and spectacular aurora displays. The increased solar storms energize the Earth’s magnetosphere, producing stunning Northern Lights that light up the night sky.

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The Solar Cycle 25 forecast, produced by the Solar Cycle 25 Prediction Panel, which is co-chaired by NASA and NOAA. Sunspot number is an indicator of solar cycle strength - the higher the sunspot number, the stronger the cycle. Credit: NOAA’s Space Weather Prediction Center

This past May, a powerful series of solar flares and coronal mass ejections (CMEs) resulted in one of the most intense geomagnetic storms seen in decades, setting the stage for breathtaking aurora displays visible across Canada. For many, it was a rare opportunity to experience the vivid greens, reds, and purples dancing across the sky.

If you didn’t catch those May displays or other recent aurora events, there’s no need to worry. With the Sun currently in its solar maximum, NASA and NOAA anticipate ongoing solar and geomagnetic storms in the coming months, which means there will be many more chances to witness the auroras.

Although the Sun is already in an active phase, pinpointing the exact peak of this cycle will take time as scientists closely monitor the number and intensity of sunspots and solar eruptions.

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Exciting research efforts are also underway to better understand the Sun's behavior during this dynamic period. NASA is preparing for a major milestone in solar exploration, with the Parker Solar Probe set to make its closest approach to the Sun in December 2024. This mission, along with other initiatives, aims to deepen our knowledge of space weather and its effects on our planet.

Here at Instant Weather, we’re committed to keeping you informed about significant solar activity and providing timely alerts for aurora viewing opportunities across Canada. As the Sun continues to show off during this solar maximum, be sure to stay tuned for updates and get ready for more spectacular light shows in the sky.

‘Strong’ Geomagnetic Storm Takes Aim at Earth; Northern Lights May Dazzle the Skies Across Canada on Thursday & Friday

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One of the most powerful solar flares in recent years erupted from the sun on Tuesday evening, classified as an X7.1 flare. Initially, it was unclear whether this flare had produced a coronal mass ejection (CME), which is a large expulsion of plasma and magnetic field from the sun’s corona.

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However, data that came in later confirmed that a CME was indeed produced and, more importantly, appears to be Earth-directed. This means that the CME is expected to impact our planet, setting off the possibility of a ‘strong’ geomagnetic storm and potentially bringing the northern lights much farther south than usual across Canada to close out the week.

The exact timing of the CME's arrival, however, remains somewhat uncertain. Forecast models suggest it could arrive anywhere between late Thursday and early Saturday. The CME might even come in multiple waves, according to the latest data.

If this happens, we could be in for two consecutive nights of auroras lighting up the skies—if the conditions align perfectly! While the Northern Lights are never guaranteed, the next couple of nights offer a decent chance to catch a breathtaking display, depending on where you are located.

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The Space Weather Prediction Center (SWPC) has issued a Geomagnetic Storm Watch, with the CME expected to reach Earth between Thursday and Saturday. Based on the latest observations, this CME could trigger G1 (minor) to G3 (strong) geomagnetic storm conditions.

The SWPC’s latest forecast predicts that a 'strong' (G3) geomagnetic storm may unfold late Thursday evening into the early overnight hours, followed by a potentially more prolonged geomagnetic storm ranging from ‘moderate’ (G2) to ‘strong’ (G3) on Friday night into Saturday morning.

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A G2 to G3 storm is strong enough to make the northern lights visible across much of Canada, especially if conditions are just right. In the past, storms of this magnitude have allowed the auroras to be seen as far south as Southern Ontario, and in some cases, even into the northern United States. In fact, the SWPC notes the possibility of the auroras being visible as far south as parts of the lower Midwest and Oregon in the U.S.

That said, space weather forecasting comes with some inherent uncertainty. The exact timing of a CME’s arrival can vary, and its intensity is often unknown until a few hours before it strikes Earth. There is usually a 12- to 24-hour window for the CME’s arrival, which means that although the current forecast favours North American viewing on Thursday and Friday nights, the event could just as easily occur during daylight hours, rendering it invisible to viewers in North America and giving those in Europe a better chance at catching the show instead.

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Aside from timing, cloud cover will also be a crucial factor in determining whether you'll have a good view of the northern lights. As of now, fairly clear skies are expected across much of southern Canada on Thursday night. Specifically, areas of Atlantic Canada, Southern Quebec, and Southern Ontario are forecasted to have little to no cloud cover during the overnight hours, which is ideal for aurora viewing.

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Further north, however, there could be widespread cloud cover that might obstruct the view around James Bay in Northern Ontario and Quebec. Similarly, Northwestern Ontario could see some cloudiness, with the exception of a pocket near the International border around Thunder Bay.

In Southern Manitoba, skies look clear south of the Interlake region, though clouds will likely impact Northern Manitoba and Saskatchewan.

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For Western Canada, Southern Saskatchewan and Southeastern Alberta are expected to have the clearest conditions. Meanwhile, much of British Columbia, along with central and northern Alberta, could see cloud cover that may limit visibility.

Check out our free app, Instant Weather for a more in-depth cloud coverage forecast specific to your exact location.

If you’re planning to watch for the auroras, another factor working in your favour this time around is the moon phase. Unlike last month’s aurora event, the moon is currently near 0% full, as we’ve just had a new moon on Tuesday night. This means that there won’t be any moonlight competing with the northern lights, making it easier to spot even faint auroras.

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When it comes to where the northern lights might be visible, it all depends on the strength of the geomagnetic storm and how it interacts with Earth’s magnetic field. Historically, during a 'strong' (G3) storm, auroras are most visible across northern Canada, including Northern Quebec, Far Northern Ontario, the Prairies, and parts of British Columbia. In these regions, the northern lights could be visible overhead and bright enough to see with the naked eye.

In southern regions, including Northeastern Ontario (Sault Ste. Marie, Sudbury, and North Bay), as well as parts of Quebec, there’s a chance of seeing the auroras overhead or just above the horizon.

This could extend into northern parts of Southern Ontario, including Muskoka, Algonquin Park, and the Ottawa Valley. However, depending on the storm's strength, auroras may only be visible along the northern horizon, and you might need a camera to capture them, as they may not be strong enough for the naked eye.

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For the rest of Southern Ontario and into Atlantic Canada, if the auroras appear, they will likely be on the northern horizon. Here, too, you may need a camera or smartphone to capture the lights, as they may be too faint to see without assistance.

Remember, light pollution can greatly impact your ability to see the northern lights, especially in urban areas. For the best viewing experience, it’s essential to get away from city lights. A resource like DarkSiteFinder can help you locate areas with low light pollution for optimal aurora viewing.

Northern Lights Timing

Many are accustomed to the precise scheduling of weather events, from thunderstorms and winter weather to solar eclipses, where timing is crucial. It’s understandable, then, that there’s a desire for a similar pinpoint timing for the best viewing of the aurora. However, the reality of predicting the best time to view the northern lights is not so straightforward.

Here’s the deal: Unlike weather events driven by terrestrial conditions, the aurora is influenced by solar activity, which is far less predictable. We can estimate that the northern lights are best viewed from just after sunset to just before sunrise, provided the skies are dark and clear. Beyond that, precise timing for peak aurora activity is challenging to forecast with current technology.

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Space weather forecasting doesn't yet allow us to predict exactly when solar energy will impact Earth. We know it's coming, but how and when it interacts with our planet's magnetic field can vary. Often, we only have a few hours' notice before the solar energy is detected by satellites.

Furthermore, the intensity of the northern lights can fluctuate significantly over short periods. You might have noticed this variance if you've observed the lights before—periods of dim activity suddenly bursting into vibrant colors. This is due to the variable concentration of solar particles interacting with our atmosphere.

While we can inform you a few hours ahead when conditions are likely to be good, predicting the exact peak of aurora activity is akin to forecasting the peak of a meteor shower; we know the best night but not the best hour.

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Eyes to the Sky! Northern Lights Could Make an Appearance Across Canada on Monday

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A powerful solar flare, reaching an impressive X4.5 rating, erupted on Saturday, sending an Earth-directed coronal mass ejection (CME) into space. This CME is expected to impact our planet, sparking geomagnetic storm conditions that could bring the northern lights much farther south than usual across Canada on Monday.

As with most space weather events, there is some uncertainty regarding the exact timing of the CME's arrival. According to the latest data, the strongest storm conditions are anticipated during the mid to late morning hours on Monday, gradually weakening throughout the day. This suggests the best viewing opportunity for the auroras may occur in the pre-dawn hours, particularly in Western Canada.

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However, this isn’t set in stone. Space weather forecasting can be tricky, and the CME might arrive later than expected, which would actually be the ideal outcome for North American skywatchers. A delayed arrival could mean a spectacular display of the northern lights over large portions of the country on Monday night.

The Space Weather Prediction Center (SWPC) is forecasting a "strong" geomagnetic storm (G3 on a scale of 5) to develop sometime on Monday. A G3 storm is potent enough to make the northern lights visible across much of Canada, provided the conditions align just right.

Historically, storms of this strength have allowed auroras to be seen as far south as Southern Ontario, and sometimes even into northern parts of the United States. In fact, the SWPC mentions the possibility of auroras being visible as far south as Pennsylvania and Iowa.

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Based on the SWPC’s latest forecast, the geomagnetic storm is expected to peak between 5 AM and 11 AM EDT (2 AM to 8 AM PDT). A moderate (G2) storm is projected to continue through the day, potentially lasting until 11 PM EDT (8 PM PDT).

If this timing holds, the best chances to witness the northern lights would be in Western Canada during the early morning hours on Monday, when the storm is at its peak. Unfortunately, for those in Ontario and Quebec, the storm may hit after sunrise, reducing the likelihood of a good aurora display.

That said, if the CME arrives later in the day, it could extend the storm into Monday night, offering a better chance for Eastern Canada to catch the auroras, assuming clear skies.

IMAGE FROM WeatherBell

Speaking of skies, Monday night’s cloud forecast looks promising for much of Canada. The latest model shows most areas should have a good view, with only Southeastern Manitoba, Northwestern Ontario, and Northern Quebec facing potential cloud cover that might obscure the show.

Southern Saskatchewan and Northern Alberta may see patchy clouds but could have breaks offering decent aurora visibility. For Southern Ontario, Quebec, and most of Western Canada, skies are expected to remain clear.

Check out our free app, Instant Weather for a more in-depth cloud coverage forecast specific to your exact location.

Another potential issue will be the full moon leading to the possibility of the northern lights appearing more dim and harder to spot. However, if the storm is as strong as forecasted, there still should be some chance to capture the show despite the bright moon.

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Northern regions of Canada, especially Northern Quebec, the Prairies and British Columbia, are almost guaranteed to see the northern lights, except for areas in Southwestern BC near Vancouver where visibility is less certain.

Zooming into more southern regions, the likelihood of seeing auroras becomes more variable. Northeastern Ontario, including Sault Ste. Marie, Sudbury, and North Bay, along with Western and Northern Quebec, have a strong chance of aurora sightings.

In Central Ontario, places like Muskoka, Algonquin Park, Bancroft, and the Ottawa Valley also have a moderate chance, as do areas around Montreal. However, the timing of the storm’s arrival remains a key factor—if it’s delayed and peaks closer to sunset, a G3 storm would likely provide an opportunity for these regions to witness the lights.

In Southwestern Ontario, the Golden Horseshoe, and southern Quebec near the American border, the probability becomes more uncertain. There’s a low to slight chance of auroras being visible here, depending on whether the storm overperforms or peaks later in the night.

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It’s important to keep in mind that light pollution can drastically affect your ability to see the northern lights. Urban areas, in particular, can drown out the skies, so you’ll need to find a dark spot away from city lights for the best chance to see the show. A resource like DarkSiteFinder can help you locate areas with low light pollution for optimal aurora viewing.

Northern Lights Timing

Many are accustomed to the precise scheduling of weather events, from thunderstorms and winter weather to solar eclipses, where timing is crucial. It’s understandable, then, that there’s a desire for a similar pinpoint timing for the best viewing of the aurora. However, the reality of predicting the best time to view the northern lights is not so straightforward.

Here’s the deal: Unlike weather events driven by terrestrial conditions, the aurora is influenced by solar activity, which is far less predictable. We can estimate that the northern lights are best viewed from just after sunset to just before sunrise, provided the skies are dark and clear. Beyond that, precise timing for peak aurora activity is challenging to forecast with current technology.

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Space weather forecasting doesn't yet allow us to predict exactly when solar energy will impact Earth. We know it's coming, but how and when it interacts with our planet's magnetic field can vary. Often, we only have a few hours' notice before the solar energy is detected by satellites.

Furthermore, the intensity of the northern lights can fluctuate significantly over short periods. You might have noticed this variance if you've observed the lights before—periods of dim activity suddenly bursting into vibrant colors. This is due to the variable concentration of solar particles interacting with our atmosphere.

While we can inform you a few hours ahead when conditions are likely to be good, predicting the exact peak of aurora activity is akin to forecasting the peak of a meteor shower; we know the best night but not the best hour.

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Snowy Surprise: Parts of Ontario & Quebec Could See Season’s First Snowflakes This Weekend

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As we enter the first full weekend of meteorological fall, Mother Nature is set to deliver a taste of autumn across Ontario and Quebec. A brief blast of cold air will cause temperatures to drop near the freezing mark during the pre-dawn hours on Saturday and Sunday.

Precipitation currently affecting Southern Ontario is expected to linger throughout the weekend. The heaviest rainfall totals are expected overnight Friday into early Saturday in Eastern Ontario, with localized amounts of 20-40 mm of rain possible.

The bigger story is when that precipitation wraps around into Western Quebec and Northeastern Ontario later on Saturday, continuing into the early morning hours of Sunday. With temperatures cooling into the low single digits and even colder air aloft, some of that precipitation may fall as wet snow.

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It appears that locations like Timmins, Cochrane, Kirkland Lake, Temiskaming Shores, Deep River, and Algonquin Park in Ontario could see their first snowflakes of the season. In Quebec, areas such as Ville-Marie, Rouyn-Noranda, Amos, and Val-d'Or may also experience wet snow.

While it's unlikely that snow will accumulate, as it will be mixed with rain and ground surfaces are still too warm, there's a chance that colder-than-expected conditions could lead to a few slushy centimetres in some areas. Any accumulation will melt quickly after sunrise on Sunday as temperatures gradually rise.

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Speaking of Sunday morning, this is when the coldest air of this brief "cold snap" is expected across Ontario and Quebec. Morning lows will likely drop into the single digits across much of Northern and Southern Ontario and Quebec. In Northeastern Ontario and the Algonquin Park region, temperatures could dip to near freezing during the pre-dawn hours, increasing the risk of frost in addition to the potential for wet snow.

Further south, the coldest temperatures in Southern Ontario will be in the higher elevations of Central Ontario, east of Muskoka, where temperatures may plunge to around 2-5°C. It will be moderately warmer in Southwestern Ontario, the Golden Horseshoe, and Eastern Ontario, with morning lows ranging from 5-10°C. Those along the shorelines of Lake Ontario, Lake Erie, Lake Huron, and Georgian Bay will benefit from the warmer lake waters, keeping temperatures above 10°C.

In Quebec, expect low to mid-single-digit temperatures in the western portion of the province near the Ontario border on Sunday morning. Eastern Quebec, including Montréal and Québec City, will see lows in the upper single digits, ranging from 6-12°C.

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WATERSPOUT RISK FOR GREAT LAKES ON SATURDAY MORNING (SORUCE: ICWR)

This cold air will also contribute to a potential waterspout outbreak over the Great Lakes this weekend. The highest risk is on Saturday, especially in the morning and afternoon, with a focus on Southern Lake Huron and Western Lake Erie. Waterspouts are also possible over Southern Georgian Bay, Western Lake Ontario, and even Lake Simcoe.

While waterspouts rarely threaten land, they can be hazardous for those on the water. In rare cases, waterspouts can come ashore, causing minor damage along the immediate shoreline.

The waterspout risk will persist into Sunday, with a focus on Eastern Lake Ontario.

Looking ahead to next week, warmer weather is expected to return to Ontario and Quebec. By late in the week, temperatures could climb back near the 30°C mark in Southern Ontario. So, while this brief taste of fall may be shocking, it looks like summer isn't quite finished yet.