In April, Thunder Bay typically sees daytime highs of 8.2°C and overnight lows around -3.7°C. Compared to the annual average high of 8.0°C, April runs +0.2°C.
April in Thunder Bay averages a daytime high of 8.2°C and an overnight low of -3.7°C.
April runs +0.2°C compared to Thunder Bay's annual average high of 8.0°C, ranking #7 of 12 months by warmth.
Plan for daytime highs near 8.2°C and cooler evenings around -3.7°C.