Trader consensus shows tight clustering around 12–16°C for Toronto’s overnight low on August 29, reflecting genuine forecast uncertainty rather than a single dominant outcome. Primary drivers include variable cloud cover that modulates longwave radiative cooling, boundary-layer wind speeds controlling vertical mixing, and the origin of the overnight air mass, which models indicate could range from cooler northerly flow to milder southerly return. Official guidance from Environment Canada and ensemble runs highlight small differences in these parameters across guidance cycles, with historical late-August climatology placing typical lows near 14–15°C as a reference point. Updated model cycles and observational data in the next few hours remain the key near-term catalysts that could shift probabilities among the leading bins.