Some footage that I had wanted to share with regards to the severe weather that came racing through much of Eastern Ontario and Southern Quebec yesterday evening (September 7th). Though storms at the level of strength in which we had witnessed last night are not too common in the month of September as compared to late June through to August, they can still very well emerge providing that the right atmospheric dynamics are in place, which was the case yesterday.

The models were projecting high instability in the specified regions since the day before the storms took form, and my level of confidence in them actually occurring grew greater earlier yesterday as helicity (windshear) values in combination with convective energy values became sufficiently high enough to support the development of strong storms by the late afternoon and early evening. Furthermore, there was plenty of surface heating during the day while the moisture content was reasonably elevated. The vigorous cold front was then the final mechanism to provide the necessary lift for the storms, and its timing was perfect as it moved into the affected regions by dusk, when heating is at its maximum. The intensity and frequency of the lightning, in particular, associated with many of these multicell thunderstorms seemed consistent with the relatively high windshear and convective energy present. Without further delay, here is some of the footage I acquired:

Storm closing in:

http://www.youtube.com/watch?v=02seugzO97E

http://www.youtube.com/watch?v=3N7us61boaY

Overhead:

http://www.youtube.com/watch?v=H_8YOJZgThU&feature=related

Ferocious thunderclap (setting off car alarms):

http://www.youtube.com/watch?v=ftQOCqcmTds

Powerful cloud to ground strike (extracted from the first video above):

http://www.youtube.com/watch?v=FfLC8ng1ac4

Photographs:

http://i18.photobucket.com/albums/b132/Rain12/CIMG3464.jpg

http://i18.photobucket.com/albums/b132/Rain12/CIMG3440.jpg

http://i18.photobucket.com/albums/b132/Rain12/CIMG3444.jpg

http://i18.photobucket.com/albums/b132/Rain12/CIMG3480.jpg

http://i18.photobucket.com/albums/b132/Rain12/CIMG3471.jpg

As expected, with the cold front's passage came a cooler, windier (from the WNW-WSW) and continuing unsettled airmass, making the atmosphere revert to more September-like weather. A pleasant start to the weekend, however, with temperatures moving up to as much as 24 C with some humidity.

Trav.

A typical Winter is possible for much of Canada (more details provided below).

Despite Fall arriving officially about a week ago (September 22nd, at 11:09 p.m.) and October just moments away, there are already many showing curiosity as to what sort of weather could prevail this coming Winter - such is to be expected given the unique nature exhibited by the very warm and snow-deprived Winter 2009-2010. El Nino was the dominant factor that governed the end of 2009 and a fair portion of 2010’s weather, notably the Winter and Spring seasons. Although El Nino vanished well before Summer, its influence continued to linger into the warmest months of the year as things quickly transitioned over to more neutral conditions (no El Nino or La Nina signatures). As it turned out, this past Summer followed closely along the lines of the models’ initial predictions with respect to temperature and precipitation, as it was very warm and humid from the end of June spanning persistently as far as the beginning of September, with small warm episodes in between following the first week of September. Thunderstorms were plentiful (some severe) and responsible for the vast majority of our precipitation since early April. Winter was undoubtedly mild (and record-breaking in numerous cases) this past year with very little snow cover across the country, and Spring continued on the same pathway, though with anomalous rainfall (below normal) patterns seen in May and unseasonably cool weather during the start of the second week of the month. June, in its entirety, was the sole exception in not following the above normal trend with respect to temperature. Now that Summer has (sadly) come to a close, Fall 2010 and Winter 2010-2011 are accompanied by an opposing force: La Nina.

El Nino has weakened considerably over the Spring with very brief neutral conditions in the equatorial Pacific since the end of April. By May, however, things started to take a little turn - negative sea-surface temperatures (SSTs) had appeared, suggesting that a cooling had commenced in the Eastern and central equatorial Pacific. The climate models predicted that these values would become increasingly negative following July, surely enough that a weak La Nina would take form. As was the case, La Nina had developed by the end of the Summer, throwing some hints that it would continue to intensify as had been predicted by most of the models beforehand. As things currently stand, La Nina is on the verge of striking moderate status and there is the possibility that it could reach borderline moderate-strong standards in time for this Winter.

Winter 2010-2011 outlook:

Temperature

With a La Nina signal in place, and assuming at least moderate strength, this tends to favor normal to slightly below normal Winter monthly temperatures in Eastern Canada, especially for January and February. La Nina frequently fosters a polar jet stream that allows for cold, dry Arctic air to descend South into much of the country, particularly the West, making for more episodes of cold overnight lows and at times some consecutive periods of frigid daytime highs - this is to a lesser extent than Western and central Canada, however.

Precipitation

La Nina Winters tend to bring with them variable amounts of precipitation, but they typically possess atmospheric conditions that are conducive to snowy seasons, especially in central and Eastern parts of Canada and the United States. With the average jet stream configuration, this would allow for strong low pressure systems to advance farther North, especially along the Eastern seaboard - I am seeing indications of those patterns with the current and recent Fall storms that brought us copious rainfall. Low pressure areas could also frequently intensify due to a nearly consistent influx of cold Arctic air descending from Northern Canada into the United States, where it would interact with warm moist air from the Gulf of Mexico further South. As such, in terms of snowfall, we could see normal to above normal snow amounts this Winter, with the first measurable snows possibly falling midway to the end of November.

Despite the overall patterns described above, this does not necessarily imply a harsh Winter by any means, but rather Winter-like. La Nina does not so much have an impact on Fall weather, but it can begin to take effect by the end of the season. All things being equal, most of Fall 2010 should be roughly average in terms of temperature and precipitation. Although it has occurred previously, it is rather unusual when a La Nina phase follows an El Nino (and vice versa) so abruptly – typically there are several successive months that show near normal conditions before either a given El Nino or La Nina event take place. La Nina itself is expected to remain with us until Summer.

If you adore Winter, then this coming season could very well be to your liking.
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Presently, the remnants of Tropical Storm Nicole are delivering a deluge of rainfall across much of Southern Quebec from the Eastern seaboard, enough to prompt rainfall warnings for affected areas, including here in Montreal. The rains should come to a close by the later overnight hours tonight, leaving mainly cloudy conditions (and a few lingering periods of light showers) for most of the day tomorrow (October 1st). Once this system clears, a strong area of high pressure will settle in, providing us with chilly October-like weather for this weekend accompanied by the possibility of our first frost for Sunday morning and Monday morning. Temperatures will rebound to seasonal standards as the work week progresses once that ridge in the West slowly migrates further East.
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EDIT: I had also wanted to share a brief video I took of Jupiter at its brightest and a full moon phase conjunction on September 20th, 2010. Jupiter was at peak luminosity on September 20th due to being in an opposition orbital positioning relative to the Earth and Sun, allowing us to see the planetary body with distinction. Jupiter has not been this bright and large since 1963.

http://www.youtube.com/watch?v=WkUJ-qG2Ctk

Jupiter continues to remain shimmering in the night sky for the next few weeks. If you wish to view it and assuming the weather permits, focus your attention firstly to the East-Southeast (ESE) to Southeast around dusk. It will then gradually continue to rise higher in the sky towards the South and will remain visible until dawn as it sets on the Western horizon - Jupiter appears as a very bright star, so it is difficult to miss it. Though a cooler and crisper airmass is gradually settling in, it will surely invite ideal evening and overnight skies later this weekend and into the work week. Jupiter will not be seen this large and bright until 2022.

Trav.

As the highly anticipated Fire on Ice event is soon to commence, I thought it would be appropriate to put together a weather forecast for those planning on attending tonight’s (December 4th) display. It should be firstly noted that a large area of low pressure that has recently moved Northward along the Atlantic seaboard is slowly retrograding Westward due to being blocked off by a strong area of high pressure situated over the Labrador Sea. Following behind this system in the long range is a typical Nor’easter, which is also expected to eventually follow the same westward track for the same reason. Consequently, with this persistent setup, today and the next several days will be generally breezy and will become rather gusty by the end of Monday through to most of Wednesday before that cold Arctic air from the West migrates eastward, bringing with it settled conditions, but cold daytime highs and particularly cold overnight lows by mid-end week. As this current meteorological setup plays some role on tonight’s weather, here is what to typically expect:

Temperature/Humidity

The area of low pressure is allowing for cold, dry air to circulate further South from the Northwest. However, saturation levels at mid levels are near 90%, so there will mostly be overcastted conditions for much of the day, keeping temperatures from dropping too rapidly during the evening-overnight period. As such, temperatures should hover around -2 to -1 C for the day and staying steady for the evening time frame. Estimated wind speeds will generate a windchill of -8 to -9 C. Humidity levels are low by end-Fall and Winter criteria.

Precipitation

Because of our close proximity to this system and due to the slight increase in atmospheric moisture associated with it, periods of on and off flurries to light snow is in the forecast for today. Total snow accumulations could be close to 10 cm by the end of Tuesday with the ongoing effect of the two systems. Chance of precipitation is 70%, both in the afternoon and evening periods.

Wind

With the positioning of the Nor’Easter, winds are likely out from the Northwest, though I am detecting a transition to predominantly westerlies by the evening hours. I understand that most spectators view the fireworks displays looking SW, so in this case, the smoke should be mostly heading to the left of these viewers. Wind speeds are light for most of the day, but I am anticipating them to become breezier anywhere between 22-25 km/h (occasional gusts of 33-35 km/h) this evening.

That’s the way the weather should operate. In general, breezy conditions, near-freezing temperatures and occasional periods of flurries to light snow are expected for today and this evening. For those of you who would like to see the presence of snow during a fireworks display, you may have your wish granted. Other than that, consistent Winter weather is making its debut this week.

Enjoy the display, for those of you in attendance, but dress accordingly for the weather.

Trav.

Thanks for that, Travis ! I was beginning to worry that we would have our first Fire on Ice without a proper forecast !

Tonight's show is named "Storm" ( "Tempête" ) ; how appropriate !

I'm heading to the Quays to interview Patrick Chandonnet, Orion's designer, as part of my enhanced Fire on Ice coverage. I have to contact each company beforehand to ask them the permission for the interview, so some displays may not have a complete coverage.

I'll write a new post in the Fire on Ice topic with the Patrick's answers, so you may want to check the topic just before heading to the event (for those who will be there tonight).

Hi STL,

No problem for supplying the weather information. And yes, the show's title certainly complements today's general weather conditions, even though this isn't a snowstorm in the strictest sense. What good timing!

I did neglect to mention something with respect to the winds. Although I am expecting smoke to be blowing mostly to the left of spectators (under the assumption that most are looking SW), the westerly winds, in this context, mean that the further East you are relative to the firing site, the higher your chances of receiving smoke. As such, try to position yourself as much to the West as possible, but at the same time not compromising your view, of course.

With the already fallen snow, there will be some blowing an drifting snow as well, so be on the lookout for that.

Enjoy the show tonight! I look forward to your review, as well as anyone else who decides to provide one.

Trav.

For those of you attending the second display of the Fire on Ice event on Saturday (December 11th), your weather forecast is calling for calm conditions and temperatures hovering again near the freezing mark. Winds are relatively light this time from, at this point, the East to ESE. There will, however, be some increasing cloudiness later in the day due to an advancing potent area of low pressure (a Colorado low) making its way Northeastward (more on this storm below).

I did previously mention that an Alberta Clipper will be passing through early this weekend. However, this system is showing signs of speeding up as compared to what was modeled in earlier projections. Consequently, this is more of a later Friday-early Saturday event, which will bring anywhere between 2-4 cm of snow within this time frame. The Alberta Clipper is responsible for pushing temperatures briefly back up to seasonal standards for Saturday and slowly through the day tomorrow (Friday).

I will provide an additional report later tomorrow to ascertain the conditions for Saturday.
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A powerful Winter storm is going to be our weather maker for the end of this weekend into the start of the work week. This system, known as a Colorado low, is rapidly intensifying because of a deepening trough in the polar jet, which is allowing for intense cold Arctic air from the West to fuel the surface low, while the low itself draws in warm moist air from the Gulf of Mexico to the South (this favors enhanced cyclogenesis, which is a term we use in meteorology to describe the intensification of a surface low due to an increase in its circulation).

I conservatively use the term "Winter storm" because of the uncertainty associated with the dominant precipitation type that will be present in Southern Quebec. By definition, a Winter storm consists of a combination of precipitation forms, including a mix of rain, snow, ice pellets and freezing rain. Conversely, a snowstorm is strictly snowfall. Because of the possible tracks that this system could take on in a few days' time, it is still a little difficult to determine how much snow will accompany it - if the system moves farther North, it will result in a Winter mix, which will prevent copious amounts of snow - if the warm front remains just to our South, then this is mostly a snow event. At this point in time, it is with a fair probability that Eastern Ontario (especially in the snowbelt areas) and Southern Quebec could largely witness snow, and if such is the case, then total accumulations could be as much as 25 cm. As such, I suspect Winter storm and snowfall watches/warnings will likely be issued within the next 36-48 hours in Ontario and Quebec as well as parts of the U.S Northeast.

Either way, a strong storm system is on the way and will make things rather messy. Because of the strong circulation and air pressure gradient associated with this system, following its departure will be a gradual return of cold Arctic air for Tuesday and the next few days. Winds also become particularly gusty (creating blowing and drifting snow) from the NW Monday night into Tuesday. The previous Nor'easter resulted in roughly 29 cm of snow here in Montreal due to its ongoing effect and because it migrated further West than was earlier predicted.

Edit: I will be able to finalize the dominant precipitation in our region after I've reviewed and analyzed the newer model runs.

Trav.

After reviewing the model runs from yesterday (Friday), here is your general weather conditions for tonight's display of the Fire on Ice event.

Temperature/Humidity

The temperature during the day are expected to be hovering close to the freezing mark and possibly attaining 1 C during the early afternoon for Saturday, courtesy of this current Alberta Clipper system. Values are expected to decline, however, by the evening-overnight period to roughly -4 to -5 C, and though the winds are light, they are enough to generate a slight windchill of -7 to -9 C during this time. Humidity levels are low, but are steadily rising for late Sunday into Monday.

Precipitation

You'll find yourselves waking up to a fresh blanket of snow Saturday morning due to the anticipated clipper affecting Eastern Ontario and Southern Quebec tonight into the early morning hours of Saturday, producing as much as 4 cm of the white stuff. Snow or flurries are not expected during the display, but there will again be increasing cloudiness associated with the upcoming potent area of low pressure (a brief analysis on that to follow). In general, partly cloudy skies should be the overall sky conditions for Saturday evening.

Wind

Wind direction is a little tricky to forecast because of the upcoming weather system, but speeds are expected to generally be light in nature at 7-10 km/h. The general direction during the morning and afternoon is Westerly to WSW, but I am detecting a shift to the NW later in the afternoon to NNW to Northerlies by the early evening, meaning that the smoke would be moving off gently to the left of viewers (assuming your focus is to the SW). Breezy Easterlies to ESE will gradually take control during the overnight period with the system being in closer proximity.

That's the way the weather should generally behave for tomorrow night's display. In summary, light NNW to Northerly winds and chilly temperatures under partly cloudy skies. Be sure to dress accordingly.
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Referring to the above post concerning the upcoming Winter storm, the newer model outputs are illustrating that this system is pushing further North as it rides along the jet stream. This suggests more of a wintery mix, but the order of precipitation types is tricky. Given the track and speed of this system from Sunday into Monday, I believe that snow will firstly take place on early Sunday afternoon, which will transition over to ice pellets and then to a brief period of freezing rain (be cautious with that) during the evening-overnight period. Following the freezing rain could be a fair dose of a cold rain during Sunday overnight into Monday before transitioning to a rain-snow mix and then briefly back to straight snow Monday evening. Temperatures rapidly fall Monday overnight into the early minus teens and making way for a cold Tuesday to Thursday, which is due to Arctic airmass that I had alluded to previously. Total snowfall amounts are challenging to forecast because of the mixed precipitation, but depending on how long the periods of snow last, accumulations could be up to anywhere between 7-11 cm (most of the snow should fall Sunday afternoon and into the evening).

Nevertheless, be prepared for a sloppy Sunday-Monday!

Trav.

Saturday evening's weather for the third Fire on Ice display (December 18th) is looking to be mostly pleasant. Models are showing the intensifying area of low pressure to the North to be pushing farther Westward by Saturday evening, which should provide an increase in clear breaks at the time. Lingering flurries are possible earlier in the day, but temperatures are finally going to rebound to seasonal standards for the weekend and at least for the next several days because of a returning southerly flow. Winds, then, are likely blowing from the South at borderline light-moderate speeds - at this point, I am detecting speeds at 12-16 km/h. In this case, assuming you're looking SW, smoke would be blowing closely to your right, so the closer you are to the water (i.e. to the South or SE), the better the chances of avoiding incoming smoke. Temperatures are holding steady around -2 to -3 C for the evening period with a windchill factor of -6 to -8 C.

I'll keep an eye on the speed of the low through tomorrow before providing the final update, as this can influence wind speed and direction. If the low speeds up, then we'll have winds that are lighter in nature, but still Southerly - if it conversely slows, then this would favor breezier conditions, more cloud cover, and winds from the SSW to even SW.
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I'm vigilantly monitoring an intensifying area of low pressure (a nor'easter) developing in the central Atlantic, which could be a weather maker for us Monday night into Tuesday. Notice that we've been receiving ongoing periods of snow/flurries (relentless lake-effect snow in SW Ontario) for a good portion of this month so far. From a meteorological standpoint, the persistent instability is attributed to a powerful ridge of high pressure stationed in the North Atlantic, and this blocking mechanism is causing the polar jet to deeply meander around it, to the point where it is flowing East to West farther North. Consequently, areas of low pressure take longer to exit to the Northeast and instead retrograde westward. "If" this blocking high remains intact for the start of the work week, it could cause the upcoming nor'easter to follow a similar track, leading to a fair amount of snowfall in Southern Quebec and Eastern Ontario. It is with a fair possibility that the unusually strong high pressure ridge is linked to the current negative phase of the Arctic Oscillation, which would partly explain the weaker polar jet stream and therefore the unseasonably cold and relatively snowy weather patterns in North America.

Oh yes, congratulations to the Montreal Canadiens with their victory over the Boston Bruins tonight.

Trav.

Following up on the previous message and after carefully reviewing the model simulations, here is a synthesis of the weather for tonight's display.

Temperature/Humidity

Temperatures are rising for the weekend and into the work week to seasonal to slightly above seasonal standards for a change. Today's (Saturday) temperatures are expected to be hovering between roughly -2 to -3 C during the afternoon and holding steady at -3 C for the early evening period. Given the light winds, the windchill factor is at -6 to -8 C. Moisture levels are low.

Precipitation

Saturation levels are high at mid levels of the atmosphere, and so mostly cloudy conditions will prevail with possible periods of flurries and light snow early in the day and into the afternoon hours. By evening, I am still anticipating an increase in clear breaks as the area of low pressure is speeding up somewhat. However, isolated pockets of flurries are still a possibility across Southern Quebec.

Wind

As the system has exhibited signs of speeding up, the winds are now expected to be more within the light spectrum ranging from 8-11 km/h from the SSW. As such, smoke should be blowing closely to your right if looking directly SW (and depending on your proximity to the firing site). However, with the tilt to the SSW, it is possible to intercept the smoke at times. As such, try to position yourself as close to the water as possible towards the SE/South or in the opposite direction to the NW or West relative to the site.

That's the way the weather should typically operate. To summarize, light SSW winds and milder temperatures under mostly cloudy skies. Isolated flurries are possible. As for the Nor'easter I spoke of in the previous post, it is still a possibility to consider over the medium term into the work week because it appears that the same upper level patterns are persisting up until that point. We'll still keep an eye on the storm, but if it does have an impact, it's just a matter of determining the dominant form of precipitation and the timing. More details on this storm in the above post.

Trav.

Thanks Travis ! Like I often say to my girlfriend regarding to your predictions about precipitation : if only Travis could be wrong for a change !

I won't be close to the water, as the building (skating chalet ?) will block part of my view (and my cameras'[img]http://montreal-fireworks.com/forum/img/smilies/wink.gif[/img]. I'll therefore live with the smoke and/or the burning remnants that may fall upon me. This is the job's risks and I assume them for the sake of my love of fireworks !

Unfortunately, B.E.M. declined to do an interview on the firing ramps (but they did accept a phone-based interview, though, even if I didn't have the time yesterday to do it), so I don't have any sneak preview for this week's display.

Will you come and see it this time around ?

STL

Hi STL,

I take it that you're hoping for some snow to fall tonight? If so, again flurries are a possibility, but it's mostly cloudy with some clear breaks. Periods of snow coming off from Lake Ontario, however, will continue on and off this afternoon and early evening. I honestly hope that my predictions for this Winter are totally incorrect!

You should largely be ok in terms of smoke, so long as you're not positioned North or NNE of the firing site.

As much as I'd like to attend the display tonight, especially considering that the weather mostly meets my standards (light winds, near-freezing temperatures, low moisture, etc.), I do have some errands to tend to this evening, unfortunately. If anything, though, I may consider the display around New Year's Eve, but again pending the weather.

I hope that you enjoy the display put on by B.E.M. tonight and, as always, I look forward to your report!

Trav.

I take it that you're hoping for some snow to fall tonight? If so, again flurries are a possibility, but it's mostly cloudy with some clear breaks. Periods of snow coming off from Lake Ontario, however, will continue on and off this afternoon and early evening. I honestly hope that my predictions for this Winter are totally incorrect!


No, what I'm saying is that you're always right on the money when you predict precipitations (and when you predict the weather, period). Therefore, I'd like that you be wrong one time or the other, as we had enough snow for a while

But, so far, the weather's been perfect for the Fire on Ice. I keep my fingers crossed that it'll stay the same until the end.

If anything, though, I may consider the display around New Year's Eve, but again pending the weather.

You're aware that it's at midnight, right ? If it's anything like last year, there will be tons of people on the Jacques-Cartier place, so arrive early if you both want to see everything and hear the music ! The people are further away than at Fire on Ice, but the maximum caliber remains 6", so it appears rather smaller from the back or so did I saw on various people's video of last year's show.

Therefore, I'd like that you be wrong one time or the other, as we had enough snow for a while

As it turns out, the winds, although in the anticipated range in terms of speed, were variable in direction through the day and interestingly never once even blew out from the South to SSW! Instead, you were faced with light winds from the opposite direction out from the NE around 8:00 p.m., and so the smoke was virtually blowing away from most spectators. All the better, right? Typically, very light winds tend to result in variable directions at a localized scale, making them tricky to forecast with a high degree of precision at specific timeframes, and temporally in general. Everything else, however, seemed to have more and less taken place as forecasted.

You're aware that it's at midnight, right ?

Yes. If there will again be tons of people (which is a fair likelihood), I will be sure to leave extra time to get there to see the display and of course to secure a good vantage point. Thanks for the notification!

Thank you once again for providing your thoughts on the display in the Fire on Ice thread. I'm delighted to know that you, to some extent, enjoyed B.E.M's display last night. Also, I wish you the very best of luck on your final exam this morning.
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***I had wanted to briefly bring everyone's attention to the upcoming total lunar eclipse that will be taking place over the course of the overnight period tonight on December 21st, 2010 (the early morning hours). The moon will firstly begin to pass into the Earth's outer shadow creating a partial eclipse (the penumbra) starting after midnight tonight at roughly 12:30 a.m. EST. Approximately an hour later around 1:30 a.m, it will begin to enter the umbral phase and reach maximum totality by 3:13-3:17 a.m. As the moon travels through the umbral shadow (Earth's inner shadow), you will notice that its color will vary from a light orange as it enters the umbral to progressively a copper-like hue by the time it attains maximum totality. As such, if you are unable to catch most of the celestial spectacle, try to focus on getting a glimpse of the moon at its greatest eclipse during the umbra shadow at 3:13-3:17 a.m. From start to finish, this eclipse is expected to endure for nearly six hours, but the umbra will last for roughly three and a half hours (commencing again close to 1:30 a.m.) with the moon gradually interchanging colors throughout. The total eclipse will be visible for nearly one and a quarter hours, starting from 2:40 a.m - incidentally, there is a phase shift about every hour elapsed. Notice that this eclipse is taking place on the Winter solstice, which is indeed a rarity - the last time this occurred was nearly four centuries ago in 1638. The next time a total lunar eclipse is expected to take place in conjunction with the Winter solstice is in 2094.

Weather, of course, determines your viewing conditions for this glamorous celestial display. The Nor'easter that I had been tracking previously will likely be having an influence on our skies for the later overnight period tonight (Monday) due to increasing cloudiness. Consequently, the latter part of the eclipse may be marred by the increasing mid-level clouds at the time. Luckily, however, there is a fair chance that the total/greatest eclipse phases may still be visible before excessive cloud cover dominates the night sky.

With respect to the weather system itself, due to the high pressure ridge starting to break down over the North Atlantic, I don't anticipate that it will retrograde too far West to be considered a significant snowstorm here in Montreal. The westard track still will, however, be enough that we could pick up some decent snowfall amounts - at this point, it could be a maximum of 10-12 cm (locally up to 15 cm, especially the farther East and NE you travel) spanning from early Tuesday (near sunrise) to early Wednesday. Winds will also pick up from the NW and will occasionally be gusty at as much as 45-50 km/h through Tuesday.

If the system continues its current projected track, then it would surely provide appropriate conditions to welcome the first official day of Winter. The Winter solstice of 2010 is due to arrive at 6:38 p.m. EST on December 21st.

Trav.

I'm sure that many of you found yourselves waking up to a picturesque scenery that Mother Nature had beautifully crafted this morning:

http://i18.photobucket.com/albums/b132/Rain12/CIMG3600.jpg

http://i18.photobucket.com/albums/b132/Rain12/CIMG3597.jpg

http://i18.photobucket.com/albums/b132/Rain12/CIMG3598.jpg

This phenomenon closely resembles ice accumulations left behind by a freezing rain/freezing drizzle event. However, the glistening white was the result of freezing fog that had taken place last night into early this morning (December 20th). As found in typical low to mid level clouds, the suspended droplets within the fog remain in liquid phase because they are well insulated and have individual nuclei surfaces on which they cling, preventing rapid freezing. Contrary to popular belief, the droplets are actually supercooled (not frozen) when exposed to ambient temperatures that are below freezing to as cold as -40 C. With this in mind, the droplets will only freeze when in contact with a surface that is at or below freezing, forming a gentle glaze on objects like trees or roofs. There isn't any significant net accumulation of ice that takes place on the coated surfaces because the rate of sublimation roughly equals that of freezing. Once temperatures drop below the -40 C threshold, the supercooled droplets solidify into ice crystals, much in the same manner as in cirrus clouds or within the anvil of a thunderstorm. Assuming, then, that there is fog present over a given area, it will be in the form of "ice fog" - this is a rather scarce phenomenon, but is common at higher latitudes and polar regions as well.

Other than that, I hope that many of you will be able to get a glimpse of the lunar eclipse tonight, especially when the moon is half way into the umbral and reaches maximum totality around quarter past 3 a.m. The transition from the orange to red hues during the moon's passage in Earth's inner shadow (the umbra) is the result of the sun's longwave radiation being refracted by aerosols in Earth's atmosphere and then casted onto the moon's surface - the shorter wavelengths of the visible spectrum are not displayed because they are scattered more efficiently by the aerosols. I'm just hoping that the clouds will be forgiving for the umbral phase, or at the very least during the greatest eclipse. For more details of the eclipse, please refer to the message above.

Edit: It seems that skies are remaining mostly overcastted, but I am expecting to see some brief clear breaks this evening and early overnight, hopefully in time for the lunar eclipse. If the weather continues to be uncooperative, I'll post a video of the eclipse here as an additional edit later tomorrow. Still, nothing beats seeing it live in person!

Edit2: As the skies are predominantly overcast (owing to that Nor'easter), here is a live webcast of the lunar eclipse:

http://www.huffingtonpost.com/2010/12/21/lunar-eclipse-2010-live-s_n_7 99517.html

Trav.

The weather forecast for Christmas evening (and the 4th Fire on Ice display) is calling for mostly tranquil conditions under chilly temperatures, low humidity, and some cloudy periods.

A strong anticyclone (high pressure area) is developing just South of Hudson bay, and this will be providing us with mostly fair conditions and below seasonal temperatures over the course of the next several days. At the same time, there is a weak disturbance that is looking to stay mainly South of the border for Christmas evening into Boxing day, but it could spread some cloudy periods and scattered light flurries during this time period. With the atmospheric setup, winds are expected to be light in nature at 7-10 km/h out from the NW to NNW, so smoke would be blowing gently off to your left during the display (again, assuming you're looking towards the SW). Temperatures could be as chilly as -8 C with a windchill factor of -12 to -13 C.

The models are also detecting another area of low pressure that will begin to rapidly intensify in the South Atlantic, gradually becoming the next Nor'easter for the holiday week in the maritimes. I don't think this system will have as much of an impact on southern Quebec as the previous one did because the jet stream is no longer configured in the way it was over the last week - that strong North Atlantic high pressure ridge has broken down.

I'll provide a final update on Christmas Eve to finalize everything.

Happy holidays everyone,

Trav.