Hello,

Compared with the last two weekends' volatile weather, as briefly mentioned in my last post, there's really nothing too much for me to cover, besides the odd cloudy period, for this coming weekend as a beautiful high pressure ridge will virtually dominate Southern Ontario, Southern Quebec and most of the Maritimes once this approaching cold front comes through later tonight and through half of the day tomorrow - could be some early morning cracklers (just a little heads up in case lol).

Highs in the mid 20s, fair skies with gentle Southerlies and a steady flow of moderate moisture should do it justice for Saturday night's display. The only thing I'd like to keep a watchful eye on is the wind speed during the evening. In short, a nice weekend is well on the way, so get out there and soak up that sunshine.

Trav.

Hi guys,

Everything in my last post still holds true for tonight. Highs in the high 20's with some mild humidity and moderate Westerly-Southwestely winds at 15-25 km/h will be the story. Dewpoint (moisture) levels are not expected to be extremely high, as this will kick in moreso on Sunday and through the week. Thus there shouldn't be too much in the way of thick smoke accumulations compared to last week. Winds themselves should be agreeable, as they will maintain their W-SW status during the evening at about 15-20 km/h, while under mainly clear skies and temperatures keeping warm at, I'd say, 22-24 C by the time 10 p.m. rolls around - virtually perfect weather.

Again, a beautiful weekend in most of Eastern Canada, but we're running the risk for thunderstorms by the time Monday-Tuesday moves in.

Notice that this weekend didn't require much updates for weather. This is all courtesy of the large high pressure ridge, thus making me having to cover much less compared to the last two volatile weeks.

Enjoy the show, although I will be in Ontario for today, so I'm not entirely positive if I'll be able to attend. We'll see what happens, but at least I can leave you guys with some great weather conditions.

Cheers,

Trav.

^^^^^

One more thing I forgot to point out, in addition to the above, is that the UV index is rather high this weekend (about 9), as is common with high pressure. So, if you plan to be out there for extended periods, please protect yourselves accordingly from the sun. Light long sleeves tend to do it justice, but if you're using sun block directly, be sure to use an SPF of 30 or more.

Trav.

Saturday's weather in Southern Quebec looks to be promising. However, a well developed "Prairie low" (currently in the making) will be consistently tracking Eastward toward Eastern Canada. For the most part, this system will be moving in a East-Northeast pathway, but its cold front will be covering a large area further South, eventually affecting virtually all of Eastern Canada at some point from Saturday through to ending Monday.

The front is expected to move through Southern, Southwestern Ontario and the U.S Midwest, during the afternoon hours on Saturday, bringing the risk of showers and heavy thunderstorms (perhaps some cells reaching severe criteria) in its wake. The good news is that I do believe, based on the model simulations, that these preliminary bands of precipitation will reach our good city by later overnight as opposed to the evening hours, but I'd still like to keep a watchful eye on the speed of the system altogether before I give a final update. The front itself is responsible for the showers and thunderstorms we will be receiving come Sunday.

May I remind you that most of the day Saturday will be very warm, as well as mostly sunny with some later variably cloudy conditions (because of the approaching front). A returning flow of moderate to high humidity is also expected (even by Friday), and therefore constant Southerlies and Southwesterlies will prevail - it's actually a very nice Saturday overall. Highs are expected to be reaching the high 20's and possibly even crossing that 30 Celsius threshold during the afternoon.

In essence, I'll be paying attention to two things - one is the speed of the front, and two are the actual wind speeds during the evening hours, especially considering that the air will be reasonably moist. Count on the winds being continuously from S-SW, though, even during the evening.

I'll provide a final update, if needed, by sometime Friday when things fall better together.

Trav.

Greetings,

I felt it was necessary to provide another update since the system has sped up in the last 12-18 hours. Most of what I said in my previous post still remains true, but now that the front is approaching at a faster rate, the risk for rain showers exists further back into the late evening hours. However, I still believe that we will miss the showers and simply be faced with the expected variable cloudiness (as stated before) to mostly cloudy skies along with some clear breaks. You'll notice the clouds themselves moving in and increasing in number later in the afternoon with the front approaching.

I'm confident that winds will pick up as we get closer to the evening from anywhere between 15-25 km/h from the S-SW because again of the front, so I don't believe we will have to worry about smoke accumulations, despite the mild-moderate humidity present at the time. Clouds will most certainly increase with the cirrus (high level) as well as the alto-cumulus (mid level) variety. Temperatures will be, again, very warm ranging in the very high 20's, possibly crossing 30 C. Humidity is not expected to be very high, but it will be mild to moderate (humidex of 32-35 C) before the cold front completely comes through. At the time of presentation, temperatures will hold steady at 23-24 C.

It's an interesting low, I mean for this time of year. The system itself is something to behold because of its uncommon low central pressure (983 millibars - surface pressure is normally 1013). We call this a "weather bomb" because central pressure within the center of the system has dropped over 24 millibars during the course of 24 hours. If this system came through a given region in the Winter, that region would easily get an upwards of 30+ cm of snow. This system is also responsible for the severe weather in the Canadian Prairies as well as in the United States, namely parts of Minnesota.

In any case, once more, I personally think that the main rains will hold off just passed 10:00 p.m. towards 11:30 and onwards, but I would still advise to have a small umbrella on standby since some introductory brief passing showers are possible in the lateevening. I'm saying this because places like Ottawa and Cornwall are both expected to receive steady precipitation on their doorsteps by as early as 8 p.m. Other than that, don't worry, a light jacket is certainly not required, unlike tonight.

Finally, the UV index is once again very high (reading of 9 by 1:00 p.m) for most of the afternoon Saturday, so protect yourselves accordingly if you're planning to be out there for extended periods.

As for Sunday, showers and isolated/embedded thunderstorms (some vigorous) are the backdrop for most of the day, including while we sleep tomorrow night.

Trav.

Those "introductory showers" I spoke of also should not be affecting us, so there's no need for an umbrella at all. The system has again slowed somewhat and will thus delay any precipitation we receive. Once again, you will notice the skies becoming mostly cloudy, as well as the winds picking up early this evening from the S-SW. Everything else I said before still holds true, including the fact that Ottawa and Cornwall have the risk for thunderstorms this evening, although now until 10:00 p.m., so that's reassuring for us here in Montreal. In this sense, please enjoy the warm weather we will be witnessing this evening, as well as the wonderful display the Portuguese have prepared for us!

As for tomorrow, the rains and storms should subside by the later afternoon hours - some storms could be rather heavy.

Cheers,

Trav.

Good day,

The atmosphere is, much like yesterday, is going to behave in an unstable manner for the next week or so thanks to constant areas of low pressure moving in from the West-Southwest and thus dominating the Eastern part of the country. Out of interest, notice that this previous/current cold front did not do so much in the way of taking away the humidity. This is because there's one area of low pressure one after the other - think of it as an express.

Now, this weekend, including Saturday, is expected to be predominantly pleasant, though again moderately humid along with highs likely attaining the high 20's. However, we're running the risk of thunderstorms to develop on Saturday as a result of pure daytime heating and not because of a cold front, like what was seen racing through late last Saturday night into Sunday. Because of the lack of a lifting mechanism, such as a cold front, I don't really anticipate much in the way of anything reaching severe criteria, nor of t-storms developing passed dusk this coming Saturday.

Friday (tomorrow), on the other hand, could be more of a dilemma. A vigorous low pressure system is on the way from Southern Ontario, making its entrance very late today and into tomorrow. Along the warm front, steady bands of rain and quite possibly some powerful thunderstorms (as what is happening currently in Ontario) are developing. This is not to say that this will be all day rains and storms, but is certainly to acknowledge that the high potential is there for large storms and for steady rainfall at times to form (huge amounts of moisture associated with this). I'm bringing this up out of concern because it may pose some occasional problems for the Australian and La Ronde crews in setting up the display for Saturday.

And just to note, the jet stream is and will be relatively zonal across the country for the next 48 hours, so this simply will allow systems to travel fairly quickly, which is in part why things will be consistently unstable.

I'll provide an additional update either later tomorrow or early Saturday depending on how well organized the models become, but things look to be alright for Saturday evening at this point in time despite the instability present.

Trav.

Anybody enjoy the storms this morning, or did they awaken you from your beauty sleep? Some of us over here lost electricity in the West Island, as well as seeing some pretty extensive flooding, but nevertheless, this is what I meant by powerful storms for today in my previous post! I got some good footage of it as well - I'll be uploading it later today. VERY loud cracks of thunder were heard and we did receive marble-sized hail mixed in with the torrential downpours.

The storms are moving towards the Eastern Townships presently and are exiting the area here, leaving moderate rainfall behind them. I'm expecting storms (many reaching severe criteria) to fire up sporadically all over the place once more with daytime heating throughout the day - there's just so much moisture to work with.

Trav.

Consistent with my last report, the newly developing showers and thunderstorms won't be affecting Southern regions of Quebec until the later overnight hours into early Sunday, in which case, Sunday will offer another round of volatile weather. This has been a typical July week, most notably for today.

Ahem...The evening hours for tomorrow will bring about simply cloudy periods to variable cloudiness (these are introducing the upcoming warm front from our new system), and very warm temperatures will dominate, despite this current cold moving through. In terms of dewpoint (moisture), there will be some mild humidity still in force throughout the day into the evening-overnight hours and the temperatures will hold steady from 23-25 C. Winds are expected to be relatively calm as both Westerlies and Northwesterlies at about 5-10 km/h - this may cause some occasional smoke build up because of the lingering humidity.

For the most part, the weather should be setting the stage nicely for the Australian performance, but I'll still be keeping a watchful eye on those winds since this could pose some periodic problems in smoke build up. Also, I hope that the rains today did not do much in disrupting the setup schedule.

That's the way the weather should work, so the Montreal skies are yours, Australia.

Trav.

Again, everything looks alright for this evening, but once more my only concern is the periodic lack of wind this evening. They will certainly be variable from between the West and the North, which may occasionally gently blow some of the smoke inconveniently towards the audience at La Ronde. There will also be mild moisture levels present, and so this is why I'm providing this final update.

And as I had mentioned with my post from the 17th of July, don't be surprised if you hear cracks of thunder or the odd rainfall this afternoon into the early evening - this is because of pure instability. Expect this pattern to persist for the next few days.

Everything else is good, so enjoy the show, and hopefully the winds won't be as tranquil during the 10-10:30 p.m. period.

Trav.

The computer weather models have been quite busy today! The good news is that the winds are expected to gain some speed during the evening (10-15 km/h) while maintaining their variable status between the West and the North. The bad news is that the risk of thunderstorms is extending itself through the entire night. I'm not surprised in the least since the air is so unstable - I spotted a storm moving through either the East end or Dowtown itself in the distance moving towards the Southeast just about an hour ago.

Please have your umbrellas on standby, and again, hope the winds are adequate enough, which they should be. Storms and convective showers are hit and miss, but let's hope it is a miss. The storms have been out there since noon developing on radar like popcorn. I personally think that we should be alright by the later evening hours following 8 p.m, though, especially with the loss of daytime heating, but then again you can't rule out the risk since the air is still moist.

I apologize for the late notice.

Trav.

Trav (and other weather maniacs), apologies if you already know this, but there's a great website with realtime radar images of the entire continent integrated with google maps - it has a resolution down to blocks of about 1km x 1km - it was easy to see the rain cells that affected La Ronde on Saturday that didn't touch the surrounding areas. Anyway, for those who don't know try: http://itsweather.com

The search function only works for US cities but it's easy enough to zoom in on Montreal (unless one is geographically challenged).

Paul.

Hi Paul,

Normally, on most radar imagery that I utilize from the Weather Channel and other major meteorological organizations when providing short term forecasts mainly deal with the actual trajectory of individual cells or bands/clusters of precipitation associated with frontal systems, and inconveniently lack the capability of zooming into a very large scaled perspective to get important details, as offered in the integrated google maps you've introduced.

So no, I was not aware that the google maps now integrated precipitation cell intensity signatures from low pressure systems, and seeing that these maps already are capable of viewing at such a large scale, it makes them rather useful in both tracking storm movement to some extent as well as especially seeing precisely which regions will, or are being affected by them. I commonly use similar radar imagery that tracks the relative motion/speed of any form of precip. on an interval of every 5-10 minutes or so, but the integral radar images combined with google maps are quite advantageous in predicting precisely which areas would be hit whenever cells come into close proximity to whatever localized area. Not only this, but looking closely at the structure and potential growth of the more severe isolated cells, or along squall lines, allow us to see if tornadic supercells are emerging (seen often as a hook shaped cell formation on a large scale), even though this is not designed to detect windshear with height. It's also handy in getting a broad picture of the strength of an updraft in thunderstorm development, and therefore identifying characteristics such as lightning intensity or hail potential.

Other than that, it coincidentally came in useful in my weather watch for today in detecting a storm earlier in where it was moving. I was expecting strong thunderstorms to develop all over, but a cell had closed into the Southeastern portion of the West Island of Montreal and had nearly produced a weak tornado near the airport this afternoon (you may hear it pop up in the news). I've also reported funnel clouds developing in the late afternoon as well towards the South shore.

As for the storms that hit the metropolitan area as well as the East end moreso than the West Island on Saturday, I had also spotted them on radar. However, although I had a clear picture of where the cells had hit, it still couldn't tell me precisely which areas these cells were affecting within these regions, or where the heaviest of the precipitation was located - this is where this kind of radar map comes into play.

A fine tool to add to the weather watch and forecasting arsenal indeed! Thank you very much for this, Paul - I'm treating it as a birthday present. I've got a feeling that I'll be making much use of it from here on out.

Now onto my report for Wednesday!

Trav.

Atmospheric instability still yet continues to dominate Eastern Canada with much moisture and a steady South-Southwesterly flow ushering very warm and humid air. The result is consistent developments of early morning sporadic showers giving way to the possibility of light to moderate thunderstorms for the afternoon and evening hours tomorrow (Wednesday).

Looks like yet another evening to have your umbrellas handy. Temperatures will easily remain mild in the low to mid 20's during the evening, while mild humidity will continue to persist. Winds should be at more of a favorable speed, and South-Southwesterlies would mean that smoke shouldn't be so much of a dilemma for the audience in the park this time around.

We'll keep a close eye on the rain/t-storm patterns as they develop through the day since the sun will be out for a fair portion of the time.

Trav.

Being on track with my last update, the forecast model projections remain the same as a merged low pressure system creeps up into Southern Quebec and most of Southern Ontario progressively through the late morning hours and gradually through to the rest of the day. As a result, the provided instability will cause scattered to isolated showers to develop in a very ubiquitous pattern (as always), along with thunderstorm cells developing throughout the afternoon and into the evening - again, most of these are light to moderate cells, but some among them can easily reach severe criteria in the afternoon to early evening due to the persistent amount of moisture readily available in the atmosphere. For the remainder of the evening, thunderstorms are still very well possible, and this will eventually give way to steadier rain bands (and embedded t-showers) coming in from our S-SW late evening and especially the overnight.

To break it down once more, there's a fair possibility that we'll hit a high reaching about 24-25 Celsius, depending of course on how long the sun endures for the day. Evening temperatures will persist into the very low 20's, and at times the air may feel a little on the cool side, so you may want to think about carrying a light sweater or jacket, in addition to the umbrella.

Finally, checking the models, because of the positioning of the system during the day and through the evening, it would suggest that winds should be blowing gently from the East-Southeast, which is again ideal in terms of direction. With respect to speeds, we should be seeing relatively light to possibly occasional moderate winds at 10-15 km/h (occasional small gusts passing just over 20 km/h).

This is quite a risky forecast, but, as always, let's hope for the best - I'll be paying close attention to the models and radar imagery today. Why is it that Canada always has these threats? It has almost always been this way since 1995.

Trav.