In September, Rio Grande typically sees daytime highs of 18.3°C and overnight lows around 12.3°C. Compared to the annual average high of 21.7°C, September runs -3.4°C.
September in Rio Grande averages a daytime high of 18.3°C and an overnight low of 12.3°C.
September runs -3.4°C compared to Rio Grande's annual average high of 21.7°C, ranking #9 of 12 months by warmth.
Plan for daytime highs near 18.3°C and cooler evenings around 12.3°C.