September was cooler and wetter than the 30-year climate normal (1981-2010).
In terms of temperature, the average anomaly for the province was -1.1C below normal. The abundant precipitation was largely from two events: post-tropical storm Dorian on the 7th and a Great Lakes/tropical moisture merge on the 24th.
See all the details in the attached final report for September and an outlook for October from Jill Maepea, Warning Preparedness Meteorologist / Client Service Operations Atlantic, Environment and Climate Change Canada / Government of Canada