Clear skies and light northerly winds overnight are the main drivers behind current trader sentiment for Toronto’s September 26 minimum temperature, with forecasts from Environment Canada and GFS ensembles pointing to a low near 9–12 °C after a sunny day reaching 21–23 °C. Radiative cooling under high pressure favors the lower end of that range, while any increase in cloud cover or wind mixing could hold readings closer to 13–15 °C. Historical September climatology shows average lows around 11–12 °C, but model spread in boundary-layer moisture and urban heat-island effects creates the observed balance between sub-7 °C and 16 °C-plus outcomes. Updated NHC-style guidance and hourly observations through tonight will narrow resolution probabilities before the daily minimum is recorded.