September weather forecast
Williamsburg, CO

Share

Weather in September

September, the first month of the autumn in Williamsburg, is still a pleasant month, with an average temperature fluctuating between 48.2°F (9°C) and 73.2°F (22.9°C).

Temperature

September heralds a minor drop in average high-temperature, sliding from August's moderately hot 79.7°F (26.5°C) to an agreeable 73.2°F (22.9°C). Williamsburg's temperature exhibits a stark contrast from daytime to nighttime, averaging lows of 48.2°F (9°C) in September.

Humidity

The average relative humidity in September is 47%.

Rainfall

In Williamsburg, in September, it is raining for 10.1 days, with typically 0.79" (20mm) of accumulated precipitation. Throughout the year, there are 108.6 rainfall days, and 10.83" (275mm) of precipitation is accumulated.

Snowfall

In Williamsburg, snow does not fall in June through September.

Daylight

The average length of the day in September is 12h and 25min.
On the first day of the month, sunrise is at 6:30 am and sunset at 7:29 pm. On the last day of September, sunrise is at 6:56 am and sunset at 6:44 pm MDT.

Sunshine

In Williamsburg, the average sunshine in September is 11.1h.

UV index

In September, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for ordinary individuals.
Note: The UV index of 4 during September translates into the following guidance:
Undertake protective steps - Preventing sun damage is advised. Avoiding the Sun during its peak radiation time around midday is a healthy practice. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat.
Updated: Jun 28, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are the temperatures in September?

In September, in Williamsburg, the average high-temperature is 73.2°F (22.9°C), and the average low-temperature is 48.2°F (9°C). The average heat index (a.k.a. 'felt air temperature', 'real feel'), which combines relative humidity and air temperature, in July is calculated to be 82.4°F (28°C).

What is the average humidity in September?

In Williamsburg, the average relative humidity in September is 47%.

How many days does it rain in September in Williamsburg?

In Williamsburg, during September, the rain falls for 10.1 days and regularly aggregates up to 0.79" (20mm) of precipitation.

When it does not snow?

In Williamsburg, Colorado, snow does not fall in June through September.

Does it snow in September?

In Williamsburg, Colorado, in September, it doesn't snow. In October, it regularly snows.

What is the average length of the day in September?

In Williamsburg, the average day length in September is 12h and 25min.

What time are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 6:30 am and sunset at 7:29 pm. On the last day of the month, sunrise is at 6:56 am and sunset at 6:44 pm MDT.

How long on average sun shines in September?

In September, the average sunshine duration in Williamsburg is 11.1h.

What is the UV index intensity in September?

In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium hazard to health from exposure to Sun's UV rays.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in September
Williamsburg, CO

Average temperature in September - Williamsburg, CO
  • Average high temperature in September: 73.2°F

The warmest month (with the highest average high temperature) is July (81.5°F).
The month with the lowest average high temperature is January (37°F).

  • Average low temperature in September: 48.2°F

The month with the highest average low temperature is July (55.8°F).
The coldest month (with the lowest average low temperature) is December (18.5°F).

Average pressure in September
Williamsburg, CO

Average pressure in September - Williamsburg, CO
  • Average pressure in September: 30.04"Hg

The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is April (29.91"Hg).

Average wind speed in September
Williamsburg, CO

Average wind speed in September - Williamsburg, CO
  • Average wind speed in September: 6mph

The windiest months (with the highest average wind speed) are January, February and March (7.5mph).
The calmest month (with the lowest average wind speed) is August (5.7mph).

Average humidity in September
Williamsburg, CO

Average humidity in September - Williamsburg, CO
  • Average humidity in September: 47%

The months with the highest relative humidity are January and February (69%).
The month with the lowest relative humidity is June (40%).

Average rainfall in September
Williamsburg, CO

Average rainfall in September - Williamsburg, CO
  • Average rainfall in September: 0.79"

The wettest month (with the highest rainfall) is July (2.2").
The driest months (with the least rainfall) are January and November (0.31").

Average rainfall days in September
Williamsburg, CO

Average rainfall days in September - Williamsburg, CO
  • Average rainfall days in September: 10.1 days

The month with the highest number of rainy days is July (19.5 days).
The month with the least rainy days is November (2.7 days).

Average snowfall in September
Williamsburg, CO

Average snowfall in September - Williamsburg, CO
  • Average snowfall in September: 0"

The month with the highest snowfall is February (5.63").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in September
Williamsburg, CO

Average snowfall days in September - Williamsburg, CO
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (8.8 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Williamsburg, CO

Average daylight in September / Average sunshine in September - Williamsburg, CO
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).

  • Average sunshine in September: 11h and 1min

The month with the most sunshine is June (Average sunshine: 11h and 54min).
The month with the least sunshine is February (Average sunshine: 7h and 0min).

Average sunshine days in September
Williamsburg, CO

Average sunshine days in September - Williamsburg, CO
  • Average sunshine days in September: 14.5 days

The month with the most sunshine days is November (24.7 days).
The month with the least sunshine days is July (4.7 days).

Average UV index in September
Williamsburg, CO

Average UV index in September - Williamsburg, CO
  • Average UV index in September: 4

The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, October, November and December (UV index 2).

Average cloud cover in September
Williamsburg, CO

Average cloud cover in September - Williamsburg, CO
  • Average cloud cover in September: 14

The months with the most cloud cover are February and April (Cloud cover 23).
The months with the least cloud cover are June, September, October and November (Cloud cover 14).

Average visibility in September
Williamsburg, CO

Average visibility in September - Williamsburg, CO
  • Average visibility in September: 6mi

The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).

Williamsburg, Colorado, USA

Weather forecast for your location

1. Click Locate me button
2. Allow the app to use your location