Normal weather for Grand Teton National Park in September

It's pleasantly warm in September in Grand Teton National Park with an average temperature of 21°C. Temperatures this month range from a low of 17°C to a high of 26°C. At night, you can expect temperatures between 2°C and 6°C.

In September, there is an average of 41 mm of precipitation, spread over 7 days. Of the total precipitation, about 1,7 cm falls as snow in September. The wind speed is around 4 Bft, mostly coming from the Southwest.

Grand Teton National Park in September		New York
Average Temperature	21°C	27°C
High Temp	26°C	31°C
Low Temp	17°C	21°C
Total Precipitation	41 mm	57 mm
Rainy Days	7 days	9 days
Total Snowfall	1,7 cm	0 cm
Snowy Days	1 day	0 days

Start of September

The month of September starts in Grand Teton National Park with warm temps, averaging around 25°C during the day and nights around 5°C. There’s little chance of precipitation. The weather’s mostly sunny and dry.

With the temperature difference between day and night, it’s smart to wear layers. A T-shirt, light pants or skirt, and a light jacket are great for the day. In the evening and morning, go for a warm jacket, sweater or hoodie, and long pants.

Mid September

By mid-September, daytime temps drop to around 21°C, with nights around 4°C. There’s a chance of some showers during this time, but plenty of dry and sunny days too.

Since it cools down at night, it’s a good idea to wear layers. During the day, a shirt, maybe a light sweater, and thin pants will do. For the evening and morning, we recommend a thick jacket, sweater, and long pants.

End of September

By the end of September, the average daytime temperature in Grand Teton National Park is around 19°C, while nighttime temps are about 3°C. A shower might pop up, but overall, the weather will be dry and sunny.

Because temperatures drop in the evening, wearing layers is recommended. During the day, a shirt, maybe a light sweater, and thin pants will do. For the evening and morning, we recommend a thick jacket, sweater, and long pants.

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UV index

The UV index is a maximum of 8 this month. That's a very high value on the intensity scale of 1 to 11. Unprotected skin can burn within 10-15 minutes.

Is September a good time to visit Grand Teton National Park?

Looking for great weather? September is a good time to be in Grand Teton National Park. The temperatures are nice, and there’s not too much rain.

Temperature records for Grand Teton National Park in September

Check out the climate of Grand Teton National Park for all months and discover the best travel time

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Daily Temperature in September in Grand Teton National Park

This chart shows the average daily high and low temperatures in September for Grand Teton National Park, in degrees Celsius. The red line represents the highs, and the blue line shows the lows. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, provide the average temperatures for this month.

Daily Precipitation in September in Grand Teton National Park

The chart below shows the average daily precipitation in September for Grand Teton National Park, measured in millimeters over the past few years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are listed at the bottom of the chart.

A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that it rained more often. But remember, it’s just an average, and every day can be different. Based on historical weather data for September, you can expect about 7 days of precipitation in Grand Teton National Park.

Daily Precipitation in September in Grand Teton National Park

Daily Snowfall in September in Grand Teton National Park

This chart shows the average daily snowfall in September in Grand Teton National Park, measured in centimeters. The bottom of the chart shows the days of the month. The data is based on historical measurements and gives an idea of the average snowfall in September.

Daily UV Index in September in Grand Teton National Park

This chart shows the average daily UV index in September in Grand Teton National Park, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.

Temperature in September in Grand Teton National Park Over the Years

This chart shows the average temperature in September in Grand Teton National Park, measured in degrees Celsius, over the past few years.

Total Precipitation in September in Grand Teton National Park Over the Years

This chart shows the average precipitation in September in Grand Teton National Park, measured in millimeters over the past years. Precipitation is always measured as water, whether it’s snow or hail.

Snowfall in September in Grand Teton National Park per year

This chart shows the average snowfall in September in Grand Teton National Park, measured in centimeters, over the past few years.

Snowfall in September in Grand Teton National Park over the past years

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Daily Climate in September for Grand Teton National Park

Click on any day in September to get detailed info about the usual weather on that day in Grand Teton National Park. Check out the historical temperatures and precipitation over the past 10 years on this day.

Average Weather in Grand Teton National Park by Month

Click on a month below to see detailed weather info for Grand Teton National Park. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.