September weather forecast
Calvin, OK

Share

Weather in September

September, the first month of the autumn in Calvin, is also a moderately hot month, with an average temperature ranging between max 84.4°F (29.1°C) and min 64.6°F (18.1°C).

Temperature

The transition into September is accompanied by a slight temperature decrease, with the average high-temperature shifting from a hot 92.1°F (33.4°C) in August to a moderately hot 84.4°F (29.1°C). Throughout the nights in September, Calvin experiences an average low-temperature of 64.6°F (18.1°C).

Heat index

The heat index value for September is computed to be a tropical 91.4°F (33°C). Exercise extra preventive actions, heat cramps and heat exhaustion are plausible. Continuous activity could result in heatstroke.
Keep in mind the heat index values are meant for areas in shade and with light wind. The heat index might be elevated by 15 Fahrenheit (8 Celsius) degrees due to direct sun exposure.
Note: The heat index, also known as 'real feel' or 'apparent temperature', is calculated by taking the relative humidity value for a specific location and factoring it into the air temperature reading. One's weather perception can be influenced by a range of factors including metabolic differences, being pregnant, and their level of physical activity. The sun, when shining directly, can have a significant impact on the perceived temperature, increasing the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. Children frequently underestimate the necessity to rest and hydrate. Thirst is a late sign of dehydration - thus, it is vital to stay hydrated, particularly during lengthy physical exercises.

Humidity

In Calvin, the average relative humidity in September is 69%.

Rainfall

In September, the rain falls for 12.5 days. Throughout September, 2.52" (64mm) of precipitation is accumulated. In Calvin, during the entire year, the rain falls for 131 days and collects up to 28.39" (721mm) of precipitation.

Snowfall

May through October are months without snowfall.

Daylight

In Calvin, Oklahoma, the average length of the day in September is 12h and 23min.
On the first day of September, sunrise is at 6:58 am and sunset at 7:51 pm. On the last day of the month, sunrise is at 7:19 am and sunset at 7:09 pm CDT.

Sunshine

In September, the average sunshine is 8.6h.

UV index

The average daily maximum UV index in September is 5. A UV Index value of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for average individuals.
Note: During September, 5 as the daily maximum UV index converts into the following advice:
Safety measures are advised. Light-skinned individuals may experience burns in under half an hour. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Clothes that are both tight-knit and comfortably loose are prime choices for sun protection.
Updated: Jul 28, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

Is it hot during September?

Calvin in September has an average high-temperature of 84.4°F (29.1°C) and an average low-temperature of 64.6°F (18.1°C). The average heat index (a.k.a. 'felt air temperature', 'feels like'), which combines relative humidity and air temperature, in September is computed to be 91.4°F (33°C).

What is the average humidity in September?

In September, the average relative humidity is 69%.

How much does it rain in September?

In September, the rain falls for 12.5 days. Throughout September, 2.52" (64mm) of precipitation is accumulated.

When it does not snow?

In Calvin, snow does not fall in May through October.

How many hours of daylight does Calvin have in September?

In September, the average day length is 12h and 23min.

What time are sunrise and sunset in September?

On the first day of September, sunrise is at 6:58 am and sunset at 7:51 pm. On the last day of the month, sunrise is at 7:19 am and sunset at 7:09 pm CDT.

How many hours of sunshine does Calvin have in September?

In Calvin, Oklahoma, the average sunshine duration in September is 8.6h.

How high is the UV index in September?

The average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a moderate health threat from unprotected exposure to UV radiation.
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
Calvin, OK

Average temperature in September - Calvin, OK
  • Average high temperature in September: 84.4°F

The warmest month (with the highest average high temperature) is August (92.1°F).
The month with the lowest average high temperature is January (48.7°F).

  • Average low temperature in September: 64.6°F

The month with the highest average low temperature is July (72.3°F).
The coldest month (with the lowest average low temperature) is January (33.3°F).

Average pressure in September
Calvin, OK

Average pressure in September - Calvin, OK
  • Average pressure in September: 29.98"Hg

The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).

Average wind speed in September
Calvin, OK

Average wind speed in September - Calvin, OK
  • Average wind speed in September: 7.6mph

The windiest month (with the highest average wind speed) is March (11mph).
The calmest month (with the lowest average wind speed) is July (7.3mph).

Average humidity in September
Calvin, OK

Average humidity in September - Calvin, OK
  • Average humidity in September: 69%

The month with the highest relative humidity is May (80%).
The month with the lowest relative humidity is August (64%).

Average rainfall in September
Calvin, OK

Average rainfall in September - Calvin, OK
  • Average rainfall in September: 2.52"

The wettest month (with the highest rainfall) is May (4.33").
The driest month (with the least rainfall) is February (1.42").

Average rainfall days in September
Calvin, OK

Average rainfall days in September - Calvin, OK
  • Average rainfall days in September: 12.5 days

The month with the highest number of rainy days is May (15.1 days).
The month with the least rainy days is January (6.7 days).

Average snowfall in September
Calvin, OK

Average snowfall in September - Calvin, OK
  • Average snowfall in September: 0"

The month with the highest snowfall is February (1.54").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in September
Calvin, OK

Average snowfall days in September - Calvin, OK
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (2.1 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

Average daylight in September /
Average sunshine in September
Calvin, OK

Average daylight in September / Average sunshine in September - Calvin, OK
  • Average daylight in September: 12h and 2min

The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 54min).

  • Average sunshine in September: 8h and 4min

The month with the most sunshine is August (Average sunshine: 11h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).

Average sunshine days in September
Calvin, OK

Average sunshine days in September - Calvin, OK
  • Average sunshine days in September: 15.5 days

The month with the most sunshine days is January (22.5 days).
The month with the least sunshine days is May (14.5 days).

Average UV index in September
Calvin, OK

Average UV index in September - Calvin, OK
  • Average UV index in September: 5

The months with the highest UV index are June, July and August (UV index 7).
The month with the lowest UV index is December (UV index 2).

Average cloud cover in September
Calvin, OK

Average cloud cover in September - Calvin, OK
  • Average cloud cover in September: 28

The months with the most cloud cover are February and March (Cloud cover 40).
The month with the least cloud cover is August (Cloud cover 20).

Average visibility in September
Calvin, OK

Average visibility in September - Calvin, OK
  • 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).

Calvin, Oklahoma, USA

Weather forecast for your location

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