Hi everyone,

As we are all well aware, the 2020 edition of Montreal fireworks has been cancelled in light of the global pandemic known as COVID-19. Traditionally, preliminary and finalized weather forecasts would be prepared in these threads within 48 hours of each display, addressing temperature, humidity, precipitation risks, and wind speed/direction.

Although no displays this year, at Fred's suggestion, I have decided to create this thread for fun to see what weather conditions would be like during the fireworks days/nights originally scheduled for this year. While no weather forecasts would be provided, this thread could perhaps still be used as a form of monitoring conditions for each of the fireworks days to see what would have likely been present for each of the eight display days, even though it would be difficult to actually verify on-site conditions during the 10:00-10:30 p.m. period. Everyone is free to participate if they wish to. I would have added "Watch" in the thread heading, as it is appropriate, but it probably would not have fit. Haha

Today (June 20th, 2020 - the first official day of Summer 2020) would have featured the opening display. As it turns out, weather conditions would have likely been practically perfect for this first show. More fitting is that this opening night and first day of Summer are part of a significant heat wave - possibly the lengthiest June heat wave in recorded history for the island if it can last for seven consecutive days.

I would expect the light SSW winds (7-9 km/h) to blow the smoke gently clear to the right of the La Ronde audience, and although thunderstorms were in the general area this afternoon (South of the island, near the New York border), they were largely driven by solar heating and so weakened quickly by late-afternoon-evening. This leaves mostly clear skies with a few clusters of cirrus for this evening. The high humidity and fairly light winds would encourage some periods of smoke accumulation, but these would usually be displacing relatively quickly enough to not obscure viewing much (depending on how many active segments there might have been). Likely 27-28 C on the Molson display, too!

Que tombe la nuit!

Trav.

It would have been a great, warm summer night to open the season! Thank you, Trav.

Fred

Thanks Trav! I was hoping you'd continue the tradition of your weather reports/predictions!

Paul

No problem, Fred and Paul! I think that I will ultimately go ahead and follow the same layout for the rest of the originally scheduled display nights as I would have done in a normal year.

Weather conditions for the second scheduled display night (June 27th) will favorably carry on with the warmer than normal pattern.

Temperature/Humidity

Temperatures should be very warm (maximum of 28-29 C), together with borderline moderate-high humidity. This is especially true as the sun gradually breaks through the cloud by late-morning This would suggest a late-evening temperature of 21-22 C (humidex of 25-26 C) at and around the firing site.

Precipitation

Due to an advancing warm front, however, isolated convective rainfall and non-severe thunderstorms will become increasingly possible, especially by late-afternoon. This would include a 30% probability of precipitation during the late-afternoon, and then 40% for the evening as convective coverage increases. Should rainfall occur persistently during the evening, then the air would cool to 18-19 C (humidex of 24-25 C).

Wind

Winds should be in the form of SSW, with speeds of 13-17 km/h during the evening period. Much like during the opening night, this would have likely allowed the smoke to blow reasonably quickly clear to the right of the La Ronde audience, despite some periods of smoke accumulation. Note that if thunderstorms are in the area, the local wind flow would temporarily be disrupted.

Trav.

I think just a light rain was present during the second half of the 10:00-10:30 p.m. (June 27th) timeframe - largely the last 10 minutes. Occasional distant lightning was also observed around the Mirabel-Saint-Jerome corridor for about 35 minutes prior to 10:00 p.m.

Trav.

Yeah, in my area, a light rain began around 10:20pm. I live in the Northern part of Montreal, and I had seen, early tonight, the rainy zone on the radar moving from the Laurentides region towards us. So I thought the rain could be starting somewhat later at La Ronde, just before or (hopefully) after the finale.

Fred

Hi Fred,

Thank you for kindly sharing these observations! Out here, in the SW West Island-Vaudreuil corridor, the light rain began at about 9:50 p.m. before gradually evolving into more of a moderate rainfall. But yes, I think the most significant of the rainfall only occurred until after display time (while during the last 5-10 minutes, a light rainfall or even drizzle was present around the firing site). Saint-Hubert airport also reported moderate to heavy rainfall by 10:50 p.m. So, very likely, the display would have been largely dry, though meeting with some light precipitation during its final 33%, or perhaps closer to the finale and/or penultimate piece (unless the display would have extended beyond 10:30 p.m.!).

Thanks, again, Fred!

Trav.

Yeah, this scenario reminds me the weather during, and shortly after the opening show on July 1, 2017. I wrote in my report of that show:

Whereas rainy and windy weather conditions were forecast for this very humid day, the sky was partially clear during the evening and wind were not strong at all. As predicted by Trav, the smoke moved gently toward the right of the audience. However, during the last two segments, the wind suddenly turned toward the audience, then toward the left of the audience. As Trav sometime writes, such fuzzy wind patterns may be associated to rainfall. Indeed, just a couple of minutes after the show (before I even put my tripod into its bag), the rain began and it soon became heavy. We were fortunate to not have such precipitations during the show itself !

Fred

Yes, as I read the weather observations of your report, the situation for June 27th, 2020 was very similar to that of July 1st, 2017! And, yes, convective rainfall and/or thunderstorms often disrupt the wind flow at the local scale, since they produce their own winds. Thus, under these circumstances, a variety of wind directions can suddenly be observed over even a matter of minutes before the broader-scale wind flow can be restored following the influence of the rainfall event. In cases of heavy rainfall approaching the firing site (usually from the West), the winds, if they aren't already, can suddenly blow towards the on-site audience.

In the absence of rainfall, when the winds are very light (i.e. less than 6 km/h), a variety of wind directions can also further be observed during a display in progress. This is because local scale factors become more important in controlling directional tendencies at those speeds, making their patterns frequently erratic.

Trav.

Weather conditions for the third display day (July 4th) should continue with the very warm/hot tendency that had developed since June 16th. As such, this day may be part of an official heat wave. While convection would be inhibited, some lift in the area would support a near-continuous layer of cirrus later in the afternoon into the evening. Therefore, a maximum temperature of 29-30 C would be favorable before cloud cover interferes by late-afternoon, but the extent of the cloud coverage would limit cooling during the evening. Consequently, the temperature would not fall lower than 26-27 C for display time. Together with moderate humidity, a humidex of 30-31 C is favorable during the late-evening.

Wind speeds would be light throughout the day (4-7 km/h), and from the North/NNW. However, by display time, speeds should increase to 11-14 km/h and from the WSW. This suggests that the smoke would frequently be displacing somewhat slowly but towards central and right-hand sections of the La Ronde audience, although particularly thick smoke accumulation is not favorable.

Another update will follow by later this evening (July 3rd).

Trav.

Conditions presented in the above post continue to be largely applicable. As such, here are the dominant weather details for the 3rd fireworks day (today - July 4th) scheduled for this year for the greater Montreal area:

Temperature/Humidity

Temperatures will continue to be very warm to hot. This would suggest a maximum of 29-30 C by mid-afternoon, potentially expanding on what is now the island of Montreal's second official heat wave for this year. By late-evening, the temperature should drop to 26-27 C. Humidity will not be particularly high, though, and so will be constrained to borderline low- moderate standards. Therefore, the humidex will be negligible, especially into the evening.

Precipitation

No rainfall is expected, as convection will remain suppressed. However, sufficient lift in the area will support a fairly uniform layer of cirrus cloud into the evening.

Wind

Winds should be in the form of light North-Northwesterlies (NNW) during the morning to early-afternoon, with speeds of 4-7 km/h favorable during this time. However, by evening, winds should shift to more of a WSW tendency with slightly stronger speeds of 11-14 km/h. This would allow the smoke to blow reasonably quickly towards central and right-hand sections of the La Ronde audience, making the display appear often murky (especially deeper into the show and following active segments). Thankfully, smoke accumulation would likely not be extensive due to the lower humidity.

If necessary, another update will follow this afternoon for evening wind direction.

Trav.

Expanding on the post above, wind speeds should continue to be light this evening (July 4th), but even lighter, at 6-8 km/h. Also, wind direction should be more in the form of WNW this evening, so the smoke would most likely move gently towards central and left-hand sections of the on-site audience (had there been a display, of course). Still, particularly excessive smoke accumulation would not be favorable in light of low humidity, but the display would become murky, largely from La Ronde's perspective, not too long after commencing.

All other details are still applicable.

Trav.

What a wonderful night it would have been... except for the wind speed and direction!

Fred

Hi Fred,

Yes, it would have definitely been another wonderful night! Although it is difficult to confirm this, at the firing site, I think the wind direction might have even been a mix between the above-specified WNW, but also NW, suggesting that the smoke would have sometimes been more directed towards left-hand sections of the audience (and towards those on the bridge watching from behind). Wind speeds also appeared a touch stronger (around 13 km/h during display time), so it seems likely that the smoke would have correspondingly been moving a little quicker, but still displacing gently, overall.

Composite radar imagery also revealed that the cloud cover was producing some local light rain just before and during display time. However, it appears that this precipitation was largely not reaching the ground/near-surface due to the dry air favorably inducing evaporation. Thus, it is likely that conditions remained dry during the 10:00-10:30 p.m. - indeed, rainfall was not reported at St-Hubert airport the entire time.

Trav.

As the very warm to hot pattern continues, conditions for the fourth scheduled display of 2020 will favorably be very warm and highly moist. Consequently, maximum temperatures of 28-29 C will be possible on Saturday, July 11th for the greater Montreal area but would feel like 37-38 C under very high humidity concentrations. Due to very high humidity, the temperature would only decline to 25-26 C, with a continued humidex of 37-38 C. With rainfall, the temperature would drop to 23 C (humidex of 32 C), since the air would already be near-saturated.

Meanwhile, July 11th presents an interesting situation in that the remnants of tropical cyclone Fay will drift North to slightly NNW and merge with another area low pressure coming from the SW. As this happens, periods of (heavy) rainfall will be favorable during the morning of Saturday. It is this rainfall that will continue to moisten the air and keep it near-saturated and buoyant. However, recent and latest analyses would suggest that breaks in the cloud deck would emerge by early-afternoon, which would effectively allow sunlight to get through regularly by this point. This would further moisten the air and cause the temperature to rise fairly close to the 30.0 C threshold. That said, due to potentially spending extensive amounts of time under cloud cover and rainfall during the morning, it seems likely that Saturday will narrowly miss reaching or exceeding 30.0 C, putting an end to what is going to be a significant heat wave by this afternoon (July 10th). That said, the periods of sunshine will encourage scattered convective rainfall and isolated thunderstorms (a few strong) by mid- to late-afternoon (60% probability of precipitation). The thunderstorm risk would continue into the evening period, but convective coverage would diminish progressively with the loss of solar heating (40% probability of precipitation by late-evening). Skies would be cloudy during the evening.

During this event, wind speed and direction would be variable. By late-evening, directional tendencies should be WSW to SW, at 11-14 km/h, suggesting that the smoke, at all altitudes, would be displacing towards right-hand sections (partly central) of the La Ronde audience. In light of such a near-saturated and highly humid environment, smoke accumulation would be rapid, especially along low-level and during more energetic segments. Still, this accumulating smoke would displace reasonably fast enough, but the display might have appeared fairly murky at right-hand sections under the thick smoke.

Another update to follow by late this evening into the early-overnight (July 10th-July 11th).

Trav.

Conditions specified above largely remain applicable for the fourth originally scheduled display day for 2020. As such, here the expected conditions for the greater Montreal area, for Saturday, July 11th:

Temperature/Humidity

Temperatures should remain very warm (maximum of 28-29 C), together with very high humidity. Due to excessive time spent in cloud during the morning hours, achieving 30.0 C, while possible, would be difficult to achieve. As such, the current heat wave is likely to come to a close tomorrow. Breaks in the cloud deck continue to be favorable by early-afternoon, and so this appears sufficient to allow the maximum temperature to reach fairly close to 30.0 C. Due to a return of excess cloud cover by evening, as well as very high humidity, late-evening temperatures of 26-27 C are likely (humidex of 36 C). If rainfall occurs, the temperature would decline to 23 C (humidex of 32 C).

Precipitation

Due to the influence of the remnants of tropical cyclone/storm Fay, periods of (needed) rainfall are likely across S. Quebec. However, because these remnants will be moving fairly quickly off to the North, a fair portion of the rainfall would be focused to the morning to early-afternoon period. Thereafter, as mentioned, the cloud deck should eventually exhibit discontinuities, although this appears to be more favorable by mid-afternoon to allow for some periods for solar heating to initiate for a few hours. As temperatures begin to rise fairly quickly in response to this, scattered thunderstorms and/or convective rainfall will also become increasingly possible. As such, the probability of precipitation should be 40% during the late-afternoon to evening. However, by late-evening and beyond, convective coverage should increase in response to enhanced lift, and atmospheric instability will remain relatively high. For this reason, thunderstorm and convective rainfall development will favorably ensue during this time (60% probability). Although mostly non-severe, a few strong thunderstorms would also be possible in this environment, including during the late-evening to mostly early-overnight. This is notably true for areas where earlier solar heating was maximized. All thunderstorms would be capable of torrential rains as their primary hazard and would increase the risk for localized flooding where they affect.

Wind

Without the influence of thunderstorms in the area, winds should generally be in the form of light Southerlies (9-13 km/h) for the late-evening (as opposed to the SW/WSW mentioned in the above post). This suggests that the rapidly accumulating smoke would be pushing narrowly fast enough clear to the right of the La Ronde audience. The display would have likely appeared hazy at right-hand sections of the display, especially along low- to mid-level, and deeper into it. This is principally due to the very high humidity and near-saturated lower atmosphere.

If necessary, another update will follow to address wind speed/direction and/or rainfall development tomorrow mid-afternoon (July 11th).

Trav.

Conditions presented above are still largely applicable, except that wind direction would be more in the form of the originally specified SW/WSW tendency. This would allow the (thick) smoke to drift reasonably quickly, at all altitudes, towards principally right-hand (partially central) sections of the La Ronde audience (if there were to be a display).

All other details remain constant.

Trav.

From what I saw on the radar, we would have experienced rainy weather conditions at the time of the display.

Fred

Hi Fred,

Yes, this display would have met with a more persistent rainfall (light to occasionally moderate intensity). Thunderstorms were lighting up the skies some distance to the East and SE, as well, at the time. Winds were also likely from the SSE to South during display time, so it seems likely that the the smoke would have been moving clear to the right of the La Ronde audience at a decent pace.

Near-saturated, damp and very humid conditions for this display night!

Trav.

On the cusp of the potential next (official) heat wave over the July 17th-July 21st period, the fifth display day scheduled for 2020 (July 15th) would likely meet with largely pleasant weather conditions. Temperatures should reach a maximum of 26-27 C (humidex of 29-30 C) under a mix of sun and cloudy periods occupying the skies throughout the day in this region. Humidity would be moderate for the day, at best, and so the disparity between the base temperature and humidex should be small. For the late-evening, the temperature should decline to 24-25 C in the greater Montreal area, but with a mild humidex of 27 C. By evening, skies should become increasingly cloudy (mid- to high-level cloud) in response to a weak North-South oriented cold front ejecting East late-day. Some isolated light rain is possible by late-evening, but due to the dry nature of the air near and at the surface, any light rain would largely evaporate before reaching the ground successfully.

Winds should be in the form of light (9-12 km/h) ENE to straight easterlies. Therefore, accumulating smoke would, at all altitudes, be moving directly and fairly gently away from the La Ronde audience, and towards those on Notre-Dame-De Lorimier streets, most likely causing the display to appear hazy from there.

Another update to follow by late this evening into the early-predawn (July 14th-July 15th).

Trav.

Conditions specified in the above posting remain valid for this originally scheduled 5th display day (first Wednesday display) of 2020. As such, presented here are the expected conditions for today (July 15th) for the greater Montreal area:

Temperature/Humidity

The maximum temperature for the day would be approximately 27 C, under borderline moderate-high humidity. This will induce a maximum humidex of 31 C. By late-evening, the temperature will not drop significantly because of sufficiently high humidity and increased cloud cover, and so 26 C is favorable (humidex of 30 C as borderline moderate-high humidity continues).

Precipitation

Unlike the previous display day, no rainfall is generally expected. This is owing to dry near-surface air and limited lift in the region, as the aforementioned cold front will stall farther West. Still, sufficient lift will encourage some cloudy periods (at mid- to high-level) by mid-afternoon and onward.

Wind

Winds continue to be in the form of ENE to occasionally NE. Speeds of 9-12 km/h are favored. This suggests that accumulating smoke, at all altitudes, would drift reasonably quickly directly away from the La Ronde audience and towards those on Notre-Dame/De Lorimier street, especially those sections closest to the bridge there; this would, therefore have likely caused the display to appear hazy from those vantage points (had there been a display).

If necessary, another update will follow by tomorrow mid-afternoon (July 15th).

Trav.

An official heat wave (or near-official heat wave) continues to be favorable for S./SW Quebec for the July 17th-July 20th period. Therefore, the originally scheduled sixth display day (July 18th) will be a part of this event. Temperatures should be hot for July 18th, with a maximum of 30-31 C by mid-afternoon, and then dropping to 27-28 C in the greater Montreal area by late-evening. Combined with hot temperatures, humidity will be borderline high to very high, and so this would generate a maximum humidex of 37 C by mid-afternoon, and 35-36 C by late-evening.

While the rainfall risk would be minimal, sparsely-distributed and briefly-sustained convective rainfall and non-severe thunderstorms will be possible in this general area during the afternoon period. Due to relying largely on solar heating, however, all of these will quickly subside not long after sunset. Late-evening skies should largely remain clear, but some modest lift in the area will favor some clusters of cirrus cloud. Winds, from the WSW, would also be somewhat breezy during the day but do become lighter by evening. WSW tendencies are also expected to shift SSW by late-evening, at 8-11 km/h, so the smoke would be drifting fairly slowly to the right of the La Ronde audience (though high-altitude smoke would be passing more so over far right-hand sections of the audience, and at a slightly quicker pace).

Another update will follow this posting by later this evening into the early-overnight (July 17th-July 18th).

Trav.

The above-mentioned weather details remain valid for this originally scheduled sixth display day (July 18th). Here are the expected conditions for the greater Montreal area for July 18th:

Temperature/Humidity

The maximum temperature is expected to be 30-31 C, with a slight decline to 28-29 C by late-evening. Because of borderline high to very high humidity, the maximum humidex should be 37 C by mid-afternoon, and then 35 C for late-evening.

Precipitation

Convection will be sparsely-distributed and largely driven by solar heating and moistening. Therefore, the probability of precipitation would effectively remain at 20-30% for the afternoon but subsiding not long after sunset. Still, some lift in the area would favor clusters of high-level cloud (cirrus) for post-sunset, but large clear breaks between them are favorable.

Wind

Winds will largely be in the form of WSW to SW for the majority of the day. Winds will be breezy (17-21 km/h) through principally the afternoon, but they will become lighter for the evening (9-13 km/h) and transition to SSW tendencies. This would allow the often rapidly accumulating smoke to drift fairly quickly to the right of the La Ronde audience, though high-altitude smoke would move over far right-hand sections of the audience.

Another update will follow by tomorrow mid-afternoon (July 18th), if necessary.

Trav.

An area of low pressure will advance NE Wednesday (July 22nd). As it does, its warm front will eventually become in close proximity to this region and will, thus, be the focus for rainfall during primarily the afternoon-evening period. Embedded non-severe thunderstorms also appear possible, but their development will likely be significantly limited. As such, it is with greater possibility for the 7th originally scheduled display day to encounter periods of (convective) rainfall, although the extent to which the rainfall will persist will be more carefully reviewed in the following update(s).

For the greater Montreal area, following some morning sunlight, the day itself should involve extensive cloud coverage as this system migrates farther NE, limiting substantial warming. The maximum temperature should reach 24-25 C (humidex of 30 C) by early-afternoon before cooling to 20-21 C once the air reaches (near-) saturation from the rainfall. This 20 to 21 C would persist for the late-evening (humidex of 29 C). North of the warm front, winds should largely be in the form of ESE, persisting into the evening. Winds are additionally light through to the evening (to 8-11 km/h). This would allow the rapidly accumulating smoke (due to high humidity and (near-) saturated air)) to slowly drift directly away from the on-site audience and towards Notre-Dame Street going North. However, there is a chance for Northeasterlies to develop for the evening, depending on the trajectory of this low pressure system. This would instead cause the smoke to slowly drift to the left of and away from the on-site audience but would displace towards portions of the bridge nearest to Notre-Dame Street and the river. This will also be closely monitored.

Another update will follow later this evening or early-predawn (July 21st-July 22nd).

Trav.

As the details presented in the above posting largely remain valid, here are the expected conditions for today (July 22nd) for the greater Montreal area for this 7th originally scheduled display day of 2020:

Temperature/Humidity

Due to a slightly more northward migration of the coming area of low pressure, the maximum temperature is likely to be 27 C (maximum humidex of 32 by mid-afternoon due to high humidity re-developing). Extensive cloud cover will continue to limit substantial warming. By late-evening, the temperature should drop only slightly, to 25 C (humidex of 31 C), though the temperature should eventually drop further, to 21 C (humidex of 27 C) as periods of rainfall gradually moisten and saturate the air.

Precipitation

As the area of low pressure’s warm front drifts North/NE, larger amounts of continuous high- to mid-level cloud will overspread this region by the early-afternoon (following more of a sun-cloud mix during the morning). However, despite this cloud cover, conditions should remain largely dry until at and following sunset, when lift becomes most magnified ahead of/along the front. Scattered convective coverage is favorable, and so a 60% probability of precipitation is appropriate for the evening. Continued limited instability should keep thunderstorm risks minimal.

Wind

Directional tendencies are mostly light ESE (8-11 km/h) for the day, but they do become more Easterly to ENE for the late-evening period (9-13 km/h). This suggests that the rapidly building smoke, at all altitudes, would move at a reasonable pace directly away from the La Ronde audience and towards those sections of Notre-Dame Street closest to the bridge. From those sections of Notre-Dame Street, the display might have appeared very murky under the high humidity and (near-) saturated air, notably deeper into the display.

If necessary, another update will follow by this mid-afternoon (July 22nd) to address wind direction and rainfall persistence/coverage for the evening.

Trav.

I am glad that smoke would have moved away from the audience at La Ronde... ;-)

I will definitely monitor the weather tonight, as there is some possibility that we could have experienced a show under precipitation.

Thank you for this forecast, Trav.

Fred

Hi Fred,

I think this display would have remained largely dry, despite consistent rainfall passing uncomfortably close to the North/NW during the 10:00-10:30 p.m. period. I think that perhaps a very light rain (or drizzle), though, might have been occurring at the firing site during the last 4-5 minutes of display time - a near-similar situation to the second display day (June 27th).

Winds also appeared to be NE to later NNE (13-16 km/h), so the smoke would have likely been moving directly away from and clear to the left of the La Ronde audience. This meant that the smoke would have likely displaced towards those on Notre-Dame Street nearest to the bridge, although going farther South of where most people would normally watch the fireworks on that street. Also, those on that section of the bridge over the river and Notre-Dame Street would have likely been receiving the smoke.

Trav.

A mid- to upper-level low will circulate over these regions for July 29th, and, thus, for the final display day originally scheduled for 2020. This trough will yield instability suitable for scattered (deep) convection, including generally non-severe thunderstorms, for the afternoon-evening period (40% probability of precipitation), though more isolated coverage for the late-evening (30% probability). The maximum temperature for the day should be 28-29 C with high (not very high) humidity, generating a maximum humidex of 33-34 C. The temperature would then drop to 25-26 C by late-evening under the same humidity concentration (humidex of 30-31 C).

Winds should be largely in the form of breezy SW to occasionally SSW. Speeds of 18-22 km/h are favorable for the afternoon, but this declines slightly for the evening, to 13-16 km/h. This would allow the smoke to drift fairly quickly to the right of the La Ronde audience, though would have likely sometimes been reaching far right-hand sections (especially the more quickly displacing high-altitude smoke). Smoke accumulation would likely not have been too excessive in this situation,

An update to follow late this evening into the predawn tomorrow (July 28th-July 29th).

Trav.

Forecast details presented in the above posting remain largely applicable, and so presented here are the weather conditions expected for the greater Montreal area for this originally scheduled final display day (8th display) of 2020 (July 29th):

Temperature/Humidity

Despite an increased density in cumulus clouds into the afternoon period, substantial solar heating within this very warm fairly humid air mass should generate a maximum temperature of 28-29 C. Borderline moderate-high humidity would allow for a maximum humidex of 33-34 C by mid-afternoon. By late-evening, the temperature should drop to 24-25 C, with a corresponding humidex of 30-31 C due to the high humidity.

Precipitation

A broad mid- to upper-level trough will be circulating over this region over the next two days. Within this feature would be a moderately unstable environment suitable for sparsely-distributed (deep) convection, including isolated thunderstorms. While generally non-severe, some thunderstorms will be capable of attaining strong to even severe standards for the afternoon period, and so intensity/coverage would more aggressively diminish during the late-evening (i.e. near midnight). Thus, a 40% probability for precipitation is favorable for the afternoon to just after sunset, but more so 30% by closer to midnight. Skies should be partly cloudy (composed of large cumulus clusters) for the evening.

Wind

Winds should largely be in the form of SSW for the day (occasionally SW). Speeds of 18-22 km/h should be present during the afternoon (occasional gusts of 29-34 km/h). Somewhat lighter speeds would then develop for the evening period, with speeds of 12-16 km/h. Therefore, fairly rapidly accumulating smoke would have likely been displacing clear to the right of the La Ronde audience, though high-altitude smoke would occasionally drift very quickly over far right-hand sections. If thunderstorms are in the area, however, then the winds would suddenly turn westerly and blow more directly towards the on-site area. Extensive smoke accumulation would have likely not been favored due to sufficiently strong speeds.

Another update, if necessary, will follow by this mid-afternoon (July 29th) to address wind direction and rainfall/thunderstorm persistence/coverage for the evening.

Trav.

The weather forecast and the radar behavior would be very stressing for tonight award ceremony and closing display!

Fred