Weather Forecasts
from the
South end of the park:
Middle of the park:
North end of the park:
Summer
Air temperatures average 75 - 85 degrees F (some days in the 90s) with lows to the 50s. Moderately high humidity. Occasional thunderstorms and dense fog. Water temperatures in summer (May to September) rise from the low 60s to highs in the mid-70s in July.
Spring and fall
Climate is variable. Temperature can drop rapidly after sunset on warm days. Wet suits may be required for river use.
Winter
Air temperatures (December to March) are normally below freezing, with frequent snow and ice storms. Water temperatures drop from the 50s to the 30s by December, with most of the river usually freezing over each winter.
Recommended Clothing
Always dress in layers in any season. Be prepared for rain and cold weather at any time. Hypothermia is possible, especially on the river, even during the summer. Boaters and anglers should be prepared for cold water.
