Record rainfall in Halifax, Nova Scotia, Canada in July 2023.
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Info on the weather event:

Following a record dry spring and several 30+°C days at the end of May, fast-moving and devastating wildfires burned through parts of western Nova Scotia and suburban Halifax. While fires burned in early June, incessant rains started squelching flames and lessening the threat of wildfires as the month progressed. By the end of June, 214 mm of rain had fallen in Halifax, nearly 2 ¼ times the average monthly total. July was also wet with 187 mm - nearly double the normal. But in July almost all the rain fell in less than two days on July 21-22 when a slow-moving trough of low pressure moved into the Maritimes. A sizable plume of tropical moisture also streamed into the region from the south and positioned over some of the warmest ocean waters ever seen in the North Atlantic, surface waters two or four degrees warmer than usual. A high-pressure system to the east enabled embedded thunderstorms to tap into the tropical air, efficiently wringing out copious amounts of water. Torrential downpours started in the afternoon of July 21 and by the end of the next day between 200 and 250 mm of rain fell across the province's southwestern shore, in parts of Halifax and in the central and western parts of the province. It was a summer’s total in one day - the most significant rainfall event in the Halifax area since Hurricane Beth on August 16, 1971. Because rains had been falling for most of the previous six weeks, the ground was already saturated with little ability to absorb further rainwater. The consistent nature of the thunderstorms was frightening. At Halifax International Airport, the heavy downpours started just before 4 pm on July 21 following several hours of fog. Over the next 28 hours, rain fell continuously during 10 thunderstorm hours in a process known as “training”. Like freight cars on a railroad spur, new thunderstorms developed as old ones dissipated. It finally stopped raining at 4 pm on July 22. Rainfall intensities were torrential – 100 mm in one hour and 173 mm in six hours in Bedford – a new national record and shattering the once in 100-year rainfall return period.

Source: https://www.canada.ca/en/environment-climate-change/services/top-ten-weather-stories/2023.html