Southern Ontario Extreme Rainfall Trends - Less Severe Rain in Toronto, Ottawa and Windsor

Ontario Climate Change IDF

The above map is for short term 15 minute durations, typically used for urban drainage design, and flood risk assessments. An interactive map and table of all Environment Canada's Ontario climate stations is available at this post.

An interactive map for all Canadian stations is available here. The following graph summarizes similar trends across Canada for shorter and longer rainfall durations (5 minutes to 24 hours).

Ontario Climate Change IDF

climate change ottawa
Ottawa Climate Change - Less Severe Storm Trends
The following charts show statistically significant decreases in rain intensity for a range of short term durations. Significant decreases have been observed in Windsor and also at the central Toronto gauge. These latter gauges have very long term records making them more reliable than shorter record stations that may no longer be in service.

climate change Toronto
Toronto Climate Change - Less Severe Storm Trends

climate change Windsor
Windsor Climate Change - Less Severe Storm Trends

Extreme rainfall trends in Canada (Environment Canada Engineering Climate Datasets):

Static Maps:

Interactive Map:

Table Summaries:

Chart and Table:

Environment Canada Denies Changes:

Contradicting Insurance Industry Claims: