September weather forecast
Saint John, KS

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Weather in September

September, the first month of the autumn in Saint John, is still a warm month, with an average temperature varying between 61.7°F (16.5°C) and 81.9°F (27.7°C).

Temperature

Saint John experiences a moderate temperature shift at the start of September, with average high-temperatures adjusting a bit from a tropical 90.1°F (32.3°C) in August to a warm 81.9°F (27.7°C). Saint John's nighttime temperature in September falls to an average of 61.7°F (16.5°C).

Heat index

For most parts of September, the heat index is estimated at 84.2°F (29°C). If one remains active during constant exposure, it might cause exhaustion and heat cramps.
Heat index specifics point out values are for conditions of shade and a slight breeze. When under direct sunshine, the heat index may be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', is a fusion of air temperature and moisture levels to demonstrate the sensation of heat. Factors encompassing physical activity, clothing, and metabolic differences have a role in shaping the individual's impression of temperature. 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 particularly relevant to babies and toddlers. Kids generally face higher risks than adults as they sweat less. Along with their large skin surface compared to their small bodies and higher heat production due to their activities, their vulnerability is increased.

Humidity

In September, the average relative humidity is 60%.

Rainfall

In Saint John, in September, during 9.6 rainfall days, 1.06" (27mm) of precipitation is typically accumulated. In Saint John, during the entire year, the rain falls for 100.8 days and collects up to 16.57" (421mm) of precipitation.

Snowfall

In Saint John, snow does not fall in May 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 7:05 am and sunset at 8:04 pm. On the last day of September, sunrise is at 7:30 am and sunset at 7:19 pm CDT.

Sunshine

In Saint John, the average sunshine in September is 9h.

UV index

In September, the average daily maximum UV index is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from unsafe exposure to UV radiation for the average person.
Note: A maximum UV index of 5 in September translates into the following recommendations:
Be mindful. Those with pale skin might receive burns in fewer than 30 minutes. The solar radiation around mid-day is intense; avoid the Sun and stay safe. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Updated: Jul 25, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the temperature in September?

September temperatures vary between a high-temperature of 81.9°F (27.7°C) and a low-temperature of 61.7°F (16.5°C). In September, the average heat index (a.k.a. 'felt air temperature', 'apparent temperature'), which takes the relative humidity and factors it into the air temperature reading, is estimated at 84.2°F (29°C).

What is the average humidity in September?

The average relative humidity in September is 60%.

How many days does it rain in September?

In Saint John, in September, it is raining for 9.6 days, with typically 1.06" (27mm) of accumulated precipitation.

When it does not snow?

May through September are months without snowfall.

Does it snow in September?

In Saint John, in September, it doesn't snow. In October, it regularly snows.

How many hours of daylight does Saint John have in September?

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

When are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 7:05 am and sunset at 8:04 pm. On the last day of the month, sunrise is at 7:30 am and sunset at 7:19 pm CDT.

How long on average sun shines in September?

In September, the average sunshine duration is 9h.

How high is the UV index in September?

In Saint John, the average daily maximum UV index in September is 5. A UV Index of 3 to 5 symbolizes a moderate health threat 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
Saint John, KS

Average temperature in September - Saint John, KS
  • Average high temperature in September: 81.9°F

The warmest month (with the highest average high temperature) is July (92.7°F).
The months with the lowest average high temperature are January and December (43.3°F).

  • Average low temperature in September: 61.7°F

The month with the highest average low temperature is July (71.2°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).

Average pressure in September
Saint John, KS

Average pressure in September - Saint John, KS
  • Average pressure in September: 29.97"Hg

The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.84"Hg).

Average wind speed in September
Saint John, KS

Average wind speed in September - Saint John, KS
  • Average wind speed in September: 11mph

The windiest month (with the highest average wind speed) is April (13mph).
The calmest month (with the lowest average wind speed) is August (9.7mph).

Average humidity in September
Saint John, KS

Average humidity in September - Saint John, KS
  • Average humidity in September: 60%

The month with the highest relative humidity is December (65%).
The month with the lowest relative humidity is July (56%).

Average rainfall in September
Saint John, KS

Average rainfall in September - Saint John, KS
  • Average rainfall in September: 1.06"

The wettest month (with the highest rainfall) is May (3.23").
The driest month (with the least rainfall) is January (0.63").

Average rainfall days in September
Saint John, KS

Average rainfall days in September - Saint John, KS
  • Average rainfall days in September: 9.6 days

The month with the highest number of rainy days is May (14.2 days).
The month with the least rainy days is January (3.7 days).

Average snowfall in September
Saint John, KS

Average snowfall in September - Saint John, KS
  • Average snowfall in September: 0"

The month with the highest snowfall is February (2.87").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in September
Saint John, KS

Average snowfall days in September - Saint John, KS
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (5.6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in September /
Average sunshine in September
Saint John, KS

Average daylight in September / Average sunshine in September - Saint John, KS
  • 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 36min).

  • Average sunshine in September: 9h and 0min

The month with the most sunshine is June (Average sunshine: 11h and 30min).
The months with the least sunshine are January and December (Average sunshine: 6h and 18min).

Average sunshine days in September
Saint John, KS

Average sunshine days in September - Saint John, KS
  • Average sunshine days in September: 17.6 days

The month with the most sunshine days is December (23.5 days).
The month with the least sunshine days is May (13.8 days).

Average UV index in September
Saint John, KS

Average UV index in September - Saint John, KS
  • Average UV index in September: 5

The months with the highest UV index are June and July (UV index 7).
The months with the lowest UV index are January, November and December (UV index 2).

Average cloud cover in September
Saint John, KS

Average cloud cover in September - Saint John, KS
  • Average cloud cover in September: 22

The month with the most cloud cover is April (Cloud cover 33).
The month with the least cloud cover is June (Cloud cover 18).

Average visibility in September
Saint John, KS

Average visibility in September - Saint John, KS
  • 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).

Saint John, Kansas, USA

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