Monday brought an additional 22 to 25 mm of rain to the Calgary area, pushing the official precipitation total for the city to 162.1 mm for the month of July (July 1 – 28, 2025). According to Environment and Climate Change Canada (ECCC), that makes this July the third wettest on record – and there are still three days to go. Monthly records have been kept for 142-years. As per the Canadian Climate Normals data (1991 – 2020), July is typically the second-wettest month of the year in Calgary, averaging 65.7 mm of precipitation or contributing about 15 per cent of the annual precipitation for the city. This July has measured nearly 100 mm of additional rain as compared to the normal amount expected for July. Calgary is known for its continental climate influences (large seasonal variations in temperatures throughout the year) and it relies heavily on the increased precipitation that occurs during its warmest months. On average, June is by far the wettest month in Calgary, with an average of 112.7 mm of precipitation. The months of May (average of 61.1 mm of precipitation) and August (average of 53.8 mm of precipitation) also contribute heavily to that annual average precipitation total of 445.4 mm. This winter and spring were drier than normal across the region, with the first 19-days of June largely continuing that trend. The final third of June was a very different story; by month’s end, June 2025 recorded a precipitation total of 94.4 mm, down slightly compared to the monthly average. More than three quarters of June’s rain this year (82.94 per cent) fell between June 20-30, 2025, a wet pattern that continued into July. A measurable amount of rain has fallen 16 out of the first 28 days in July, with a few significant rain events enhancing the overall precipitation total. Normally, in July, it will rain just shy of 13 days out of 31. Four of those days will include accumulations equal to or greater than five mm, two of those days will include accumulations equal to or greater than 10 mm, and (on average), there will be less than one day in July (0.2-days) with accumulations equal to or greater than 25 mm. According to data from Environment and Climate Change Canada, as of July 28, there have been eight days so far this month with precipitation equal to or greater than five mm (four days more than normal), six days recorded precipitation equal to or greater than 10 mm (four days more than normal), and there were two days with precipitation measurements equal to or greater than 25 mm (1.79 more days than normal). The rainiest day this month was July 14, when 38.8 mm of rain was recorded at the official ECCC weather station at the Calgary International Airport. It typically takes a four-month period (123 days) to produce 66 per cent (293.3 mm) of the annual precipitation in Calgary (over the months of May, June, July and August). There has been 256.5 mm of precipitation (58 per cent of the annual total) that has fallen over 58 days, with the bulk of that occurring in just 39 days (between June 20 - July 28, 2025). This has obviously created some challenges as persistent, large-accumulation rain events often exceed the surface capacity to absorb water – or more simply – the ground becomes saturated when too much rain falls over too short of a period of time forcing excess water to be displaced. Not surprisingly, over the past six weeks water pooling, overland flooding, high water levels and early-morning dense fog events have all been observed in and around Calgary. The final days of July will bring a more stable weather pattern – as a dominant ridge of high pressure becomes the main weather-maker for B.C. and southern Alberta. Daytime highs across the region will sit in the mid-to high 20s on Tuesday, and around the high 20s to low 30s for Wednesday and Thursday. The final few days of July should remain dry in Calgary, meaning it is unlikely the city will climb the standings for precipitation records. According to ECCC, the second-wettest July on record was in 2016, with a total of 216.1 mm of rain, and the wettest July on record occurred in 1927 after 245.4 mm fell over the 31 days.
