Waterloo region saw wettest March in 15 years, weather station reports - CBC

El Niño left its fingerprints all over the beginning of autumn across North America as heavy rains brought deluge to some communities and left neighbouring areas high and dry. A striking pattern developed throughout the continent as plumes of tropical moisture streamed from both the Gulf and the Pacific. Intense deluges brought significant totals to areas that hardly see any rain this time of year. DON’T MISS: Staying safe from flash floods, a serious and deadly hazardSharp contrasts between soaked and parchedThe overall setup across North America during the first month of autumn magnified rainfall extremes in both directions. A stubborn ridge of high pressure over the Southeast kept the active storm track flowing from the U. S. Southwest toward the Midwest, largely missing southern Ontario as it plunged back toward the south. Many communities from southern New Mexico to central Iowa saw one of their wettest Septembers on record after the extremely active eastern Pacific hurricane basin pumped excess moisture inland. Albuquerque, New Mexico, picked up nearly 400 per cent of its normal monthly rainfall.

Toronto and Montreal have remained above the freezing mark every day for almost six months. While frosts and even some snowflakes have intruded across parts of Ontario and Quebec in recent weeks, the two cities have yet to reach that magic number. What’s even more remarkable is that a handful of communities across the southern United States have already dipped to the freezing point--and some have even seen accumulating snowfall. DON’T MISS: Official: Canada records first -30°C reading of the seasonThe last time we saw a freezing temperature in either Toronto or Montreal was the second-to-last week of April. Toronto hit -1.3°C early on April 20, while Montreal dipped to -2.0°C the following morning. Our average first frost in both cities occurs right around the middle of October. But warmer-than-normal years can see this milestone slide several weeks past due. Montreal once had to wait 207 consecutive days for its first frost, with the city’s first subfreezing temperature in 2017 waiting until Nov. 7. The latest Toronto’s had to wait to hit the zero-degree mark was Nov. 13, 2022.

Tropical cyclones top the list of nature’s most powerful storms. Larger than tornadoes and more intense than any single thunderstorm, these systems can change the landscape when they swirl ashore. A handful of tropical cyclones take full advantage of their surroundings to achieve the apex of their potential, the strongest storms nature can produce. DON’T MISS: What’s the difference between hurricanes, typhoons, and cyclones? Tiny fraction of storms achieve upper limitsOnly about 4 per cent of all the world’s recorded tropical cyclones have reached the equivalent of Category 5 strength. Most tropical cyclones are relatively weak and short lived because it’s tough for all the necessary ingredients to align just right. But explosive development can result when all those factors come together in perfect harmony. Strongest Winds: Hurricane PatriciaAn exceptionally favourable setup off the western shores of Mexico in late-Oct. 2015 allowed Hurricane Patricia to grow into the world’s strongest hurricane since reliable observations began in 1966.

While there have been some weather hiccups in October across Canada, one commonality is the lack of fall storms. The month has brought a very different flavour to parts of the country, compared to September's weather. October started with summer-like warmth in Ontario and Quebec, while the West endured some chilly temperatures. That pattern has since flipped. But there haven't been many of your typical fall storms this season, making for a super-dry pattern in many areas in Canada. Let’s dive into why the storms are absent so far. DON'T MISS: What does a classic fall storm look like in your part of Canada? What fuels fall storms? A split flow, in which the jet stream literally splits in two, will prove a prominent feature during the second half of October, promoting a less-consolidated jet stream that would otherwise impact the coast of British Columbia throughout autumn. Some of that energy is being redirected down toward California, a change that’s significantly affecting our weather patterns across Canada.