Where did the thunderstorms go in S. Ontario? Answers here
Saturday, June 11, 2016, 8:26 PM - Ticked about the lack of thunderstorms? We are too. Saturday’s thunderstorm forecast in southern and central Ontario was an extremely challenging one, which had forecasters pulling their hair out.
Days in advance, Saturday had boom or bust written all over it. As many of you know, we received the bust.
SUMMER 2016: Visit the Summer Forecast Guide to the Season for the 2016 Summer Forecast, Fall Weather Preview and much more
On Friday afternoon, forecasters were highlighting the threat for severe, isolated thunderstorms across southwestern Ontario and the Golden Horseshoe. We attempted to convey that the majority of people would not see storms, but rather beautiful sunshine. However, if an isolated thunderstorm did develop, it could quickly become severe. Some forecast models were even outputting tornado threats across regions of southern Ontario.
As you can imagine, there were multiple factors that needed to be considered (watch the link below where Jaclyn Whittal and myself discussed the risk on Friday).
First, the lack of trigger across southern Ontario that would cause thunderstorms to ignite. Much like having a tank of gasoline, until you put a match to it (the trigger), you won’t get anything explosive. It’ll just be a tank of gasoline. In our case, we only had a weak trough moving through the warm sector and no major trigger (for example, a powerful cold front).
Secondly, thunderstorms from northwestern Ontario would track Friday overnight into the south, affecting how unstable our atmosphere would be on Saturday. Below you can see Friday's NAM Supercell Composite forecast for Saturday, June 11 showing a widespread thunderstorm risk.
As the complex storm system headed southeastward across the Great Lakes, it gave a wide swath of heavy rain and frequent lightning. Most woke up to either clearing conditions or heavy downpours. As the morning wore on and atmospheric soundings came in, it became clear that the atmosphere, as speculated, would be mixed too much to maintain its initial instability and thunderstorms seemed very unlikely from this point onward.
Heading into the summer months, this type of "boom or bust" will likely occur again. The best thing to do is check back for weather updates regularly since the atmosphere can change drastically. If planning outdoor activities during a day with a thunderstorm threat, simply have a plan to head indoors and check radar if possible. It doesn’t mean cancelling your plans, but rather, having a backup plan.
It’s extremely difficult to explain the uncertainty and variety of weather you can experience in a day and in just one weather icon. We describe what the icon cannot in articles, tweets and further information shared online and on television.
Luckily, for those who do not share my love for thunderstorms, cooler, stable air is coming in for Sunday, with temperatures in the high teens and low 20s across Ontario.