Why it's so tricky to predict the weather in southern Alberta
Meteorologists say Calgary is an 'incredibly difficult' area to forecast
Before heading outside on June 15, Soraya Karimy looked at her phone's weather app to check the air quality, as wildfires burning across Western Canada this season have repeatedly sent waves of smoke wafting over the city.
Karimy's device told her the air quality was on the low end of moderate, healthy for most people. But when the retired engineer stepped out of her door, she found sky hazy and the air heavy with wildfire smoke.
"We went out, and I couldn't breathe," Karimy said, adding she quickly began to suffer from a headache.
According to records from the Calgary Region Airshed Zone, the air quality quickly deteriorated that day, spiking to more than double the Alberta Ambient Air Quality Guideline for fine particulate matter — the harmful particles that can lodge deep in a person's lungs.
The experience left Karimy wondering: Why didn't the forecast get this right?
"Not only can they not forecast the future, they are not up to date to the current situation that we are in," she said.
Yet, meteorologists and weather experts say the accuracy of their forecasts has actually improved over time, noting Calgary's location makes weather notoriously difficult to anticipate.
Some also point to a disconnect between the information provided across various platforms and the public's interpretation of it, be it a quick glance at an image on an app or reading highly curated forecasts for a specific region.
Niche forecasters
Frustration over the state of weather forecasting has long been felt by Stephen Vandervalk, a farmer in Fort Macleod, roughly 150 kilometres south of Calgary.
The regional vice president of the Western Canadian Wheat Growers Association said forecasts from many apps and organizations such as Environment and Climate Change Canada are unreliable.
"They can't forecast rain if it was hitting them in the face," said Vandervalk.
As he depends on weather forecasting for his livelihood, Vandervalk checks various weather apps and websites several times a day.
But what he's come to rely on is a private forecaster, based in the United States. He pays hundreds of dollars a year for the service, but he says it's worth every penny for its detailed forecasts.
"[They've] got a Prairies one and it comes out every morning, and that one is far, far more accurate," he said.
Such subscription-based weather forecasting companies cater to more than just farmers. Businesses in sectors from aviation to renewable energy are paying for detailed forecasting to help them make day-to-day business decisions.
Standing by the forecast
While Vandervalk finds Environment Canada's rain forecasting spotty, he said the agency's wind forecasts have historically been reliable, as have its radar.
Sara Hoffman, a meteorologist for Environment Canada, stands by the agency's forecast for the region, but she noted the Calgary area is "incredibly difficult" to forecast.
"If Calgary were just a little bit further east or a little bit further west, I think the forecasts would be a lot … more consistent," she said.
While Hoffman said the agency is open to criticism and feedback, she said what people see on their phone's generic weather app is not coming from Environment Canada.
"I think folks assume that it's all us," she said.
She added that, in her opinion, other apps are black boxes when it comes to what type of modelling or information they are using to build their forecasts.
Chris Scott, chief meteorologist for The Weather Network, said in a statement that forecasts, at least for his company, are becoming more accurate over time.
"The expertise of our forecast meteorologists who constantly analyze the data, combined with the improvement of computer models, means that we should continue to see improvement in the years to come," he said.
Scott also emphasized the Calgary area is particularly tricky to forecast.
"With the possible exception of Denver, Calgary sees some of the wildest swings in day-to-day weather of any North American city," he said.
This trickiness, Scott explained, is due to the city's geographical location, close to the Rocky Mountains and far from any large body of water, which would act as a moderating presence.
"Low pressure systems often develop right over Alberta (the well-known Alberta Clipper) because of this unique geography," he said.
"Within a given month, the weather pattern can have varying levels of predictability depending on the jet stream location. Additionally, spring and summer can be a very difficult time to forecast precipitation since we tend to get more convective precipitation — it's like trying to predict which popcorn kernel will pop first."
A matter of perception
Peter Neilley, the director of weather forecasting sciences for The Weather Company, which operates in the United States, said whether a forecast is perceived as accurate can depend on how it's understood.
"Sometimes the ability to make an appropriate decision is dependent on how well the information was conveyed to you," he said.
"When you relate the forecast in those terms, there can be this increased perception of accuracy, even though the fundamental quantified accuracy might not be any different from a source that didn't express it in terms you understood," he said.
Neilley said current science, in general, provides reliable probabilities for events such as thunderstorms or rain showers. However, he noted certain scenarios, such as the movements of wildfire smoke, are particularly difficult to predict.
"Sometimes just a few degrees difference in which direction the wind is blowing, which is probably beyond our ability to be accurate, can make all the difference," he said.
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