Just a few additional details to add to the above posting. First, gusty winds this evening will produce an apparent chill in the air (given enough time), especially as temperatures cool further later in the evening. That said, I will boost temperatures slightly to 19-20 C (humidex of 22-23 C) for late this evening.

Also, scattered convective rain showers could persist in the area until a little following sunset because of continuing lift supplied by the trough, and convective coverage will be reduced by not long after sunset. Partly cloudy skies (consisting of residual clusters of cumulus and isolated clusters of cirrus) will be present this evening.

Wind gusts of 38-43 km/h (base speeds of 23-28 km/h), from the SW, will continue this evening, so there is still a risk for brief delays since gusts are sometimes hovering around the 40 km/h threshold. Smoke from the fireworks should be moving very quickly towards right-hand sections of the La Ronde audience. Higher altitude smoke could also be moving more quickly and in the same general direction (partially towards central sections of the audience, but mostly right).

*For all other information, please refer to the above posting.
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And so concludes the weather forecasts for this fireworks season. The skies have certainly been quite active this year. I continue to provide weather outlooks for this general area on Facebook whenever extreme weather becomes favorable, so please feel free to visit my page!

Trav.

I thought that it would be appropriate to put together a weather outlook for today’s display (September 3rd), just in case anyone was interested. As such, here are the conditions expected for this afternoon into the early-evening for the greater Montreal area.

Temperature/Humidity

Temperatures are expected to be quite chilly through the day, with the warmest values occurring during the morning period (12-13 C). Due to persistent rainfall through principally the afternoon, saturated air after maximum evaporative cooling should maintain temperatures at around 11-12 C, including into the evening period. Humidity should be borderline low-moderate, given that the air will remain saturated at about 11-12 C. This will give the air a somewhat piercing cold feel, even with gentle breezes. Have a jacket and head covering equip.

Precipitation

The remnants of Tropical Depression Harvey will combine with a New England low pressure system and yield a fair amount of rain across extreme S./SW Quebec, with 18-24 mm possible over the resultant system’s duration. Most of this rain should occur during the early-afternoon period towards about sunset. Into the early-evening, rainfall rates appear to drop slightly due to weaker lift in the area, with rainfall becoming somewhat more scattered in distribution. This should cause rainfall to become a little more on and off as the evening progresses, with cloudy conditions in between. Rainfall should largely end near midnight. Cloud heights will also be quite low through the day (including the evening), and the air will be damp.

Wind

The circulation of this system by the early- to mid-evening period suggests mostly light ESE to SE winds, with speeds of 9-12 km/h. Speeds are somewhat breezier during the late-morning to early-afternoon (17-21 km/h), with similar directional tendencies (typically ESE), but they weaken to lighter standards by late-afternoon. As such, the smoke should be moving slowly directly away from the La Ronde audience, and slightly to the right (especially smoke associated with high-altitude shells). Periods of smoke accumulation will be favorable due to saturated air, although particularly extensive accumulations are not expected with lower humidity levels. The Easterly component in the wind fields should also help with viewing for those at La Ronde. The damp, saturated air, however, could often negatively affect the color richness of the fireworks.

If necessary, another update will follow this afternoon (September 3rd) to address wind velocity and rainfall character.

Trav.

Just in case anyone was interested, my Fall-Winter 2017-2018 outlook (and review of Spring and Summer 2017) is available at the following link. I also provide a preliminary outlook for Spring and Summer 2018. The document was released on September 22nd, 2017 (the first official day of Fall 2017):

https://www.facebook.com/notes/travis-moore/spring-summer-2017-and-a-l ook-ahead-to-late-fall-winter-2017-2018/10155516359091346/

Cheers,

Trav.