In fall, the heat of the summer gives way to cooler temperatures and drier weather, making it an ideal time to visit Zion National Park. Along the Virgin River, cottonwoods turn golden yellow and bigtooth maples add splashes of scarlet to the canyons and trails. Favorable conditions prevail for hiking and canyoneering, but be sure to check the weather forecast, flash flood potential ratings, and the temperature of the river before exploring the park. Day and night temperatures can differ by over 30°F/17°C. Consider dressing in layers to prepare for changes in temperature.