September weather forecast
Grain Valley, MO

Share

Weather in September

September, the first month of the autumn in Grain Valley, is still a warm month, with an average temperature ranging between max 78.1°F (25.6°C) and min 59.5°F (15.3°C).

Temperature

With the onset of September, the average high-temperature subtly recedes from August's moderately hot 84.6°F (29.2°C) to a still warm 78.1°F (25.6°C). During the nights in September, Grain Valley experiences a consistent average temperature of 59.5°F (15.3°C).

Humidity

The average relative humidity in September is 75%.

Rainfall

In Grain Valley, during September, the rain falls for 12.5 days and regularly aggregates up to 2.6" (66mm) of precipitation. In Grain Valley, during the entire year, the rain falls for 136.1 days and collects up to 28.78" (731mm) of precipitation.

Snowfall

In Grain Valley, snow does not fall in June through September.

Daylight

The average length of the day in September is 12h and 26min.
On the first day of the month, sunrise is at 6:46 am and sunset at 7:46 pm. On the last day of September, in Grain Valley, sunrise is at 7:12 am and sunset at 7:00 pm CDT.

Sunshine

In September, the average sunshine is 9.3h.

UV index

The average daily maximum UV index in September is 5. A UV Index reading of 3 to 5 represents a medium vulnerability from exposure to the Sun's UV rays for the ordinary person.
Note: An average UV index of 5 in September transforms into this advice:
Adopt protective measures - Suggestions to resist sunburn are offered. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation.
[Resources]

Frequently asked questions

What is the usual temperature for Grain Valley in September?

The average high-temperature, in September, in Grain Valley, is 78.1°F (25.6°C), while the average low-temperature is 59.5°F (15.3°C). The average heat index (a.k.a. 'apparent temperature', 'real feel'), which takes the relative humidity and factors it into the air temperature reading, in August is evaluated at 93.2°F (34°C).

What is the average humidity in September in Grain Valley?

The average relative humidity in September in Grain Valley, Missouri, is 75%.

How much does it rain in Grain Valley in September?

In September, in Grain Valley, Missouri, the rain falls for 12.5 days. Throughout September, 2.6" (66mm) of precipitation is accumulated.

When it does not snow in Grain Valley?

In Grain Valley, Missouri, snow does not fall in June through September.

Does it snow in Grain Valley in September?

In Grain Valley, Missouri, in September, it doesn't snow. In October, it regularly snows.

What is the average length of the day in September in Grain Valley?

In September, the average day length in Grain Valley is 12h and 26min.

What time are sunrise and sunset in September in Grain Valley?

In September, on the first day of the month, sunrise is at 6:46 am and sunset at 7:46 pm. On the last day of the month, in Grain Valley, sunrise is at 7:12 am and sunset at 7:00 pm CDT.

How many hours of sunshine does Grain Valley have in September?

In September, the average sunshine duration in Grain Valley, Missouri, is 9.3h.

How high is the UV index in September in Grain Valley?

In Grain Valley, 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
Grain Valley, MO

Average temperature in September - Grain Valley, MO
  • Average high temperature in September: 78.1°F

The warmest month (with the highest average high temperature) is July (86.4°F).
The month with the lowest average high temperature is January (37°F).

  • Average low temperature in September: 59.5°F

The month with the highest average low temperature is July (68.4°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).

[Resources]

Average pressure in September
Grain Valley, MO

Average pressure in September - Grain Valley, MO
  • Average pressure in September: 30.01"Hg

The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).

[Resources]

Average wind speed in September
Grain Valley, MO

Average wind speed in September - Grain Valley, MO
  • Average wind speed in September: 7.1mph

The windiest months (with the highest average wind speed) are February and March (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).

[Resources]

Average humidity in September
Grain Valley, MO

Average humidity in September - Grain Valley, MO
  • Average humidity in September: 75%

The months with the highest relative humidity are May and June (79%).
The month with the lowest relative humidity is October (70%).

[Resources]

Average rainfall in September
Grain Valley, MO

Average rainfall in September - Grain Valley, MO
  • Average rainfall in September: 2.6"

The wettest month (with the highest rainfall) is May (4.13").
The driest month (with the least rainfall) is January (1.06").

[Resources]

Average rainfall days in September
Grain Valley, MO

Average rainfall days in September - Grain Valley, MO
  • Average rainfall days in September: 12.5 days

The month with the highest number of rainy days is May (17.6 days).
The month with the least rainy days is January (5.2 days).

[Resources]

Average snowfall in September
Grain Valley, MO

Average snowfall in September - Grain Valley, MO
  • Average snowfall in September: 0"

The month with the highest snowfall is February (3.9").
The months with the least snowfall are June, July, August and September (0").

[Resources]

Average snowfall days in September
Grain Valley, MO

Average snowfall days in September - Grain Valley, MO
  • Average snowfall days in September: 0 days

The month with the highest number of snowfall days is February (6.6 days).
The months with the least snowfall days are June, July, August and September (0 days).

[Resources]

Average daylight in September /
Average sunshine in September
Grain Valley, MO

Average daylight in September / Average sunshine in September - Grain Valley, MO
  • Average daylight in September: 12h and 2min

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

  • Average sunshine in September: 9h and 2min

The months with the most sunshine are June and July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 5h and 0min).

[Resources]

Average sunshine days in September
Grain Valley, MO

Average sunshine days in September - Grain Valley, MO
  • Average sunshine days in September: 16.4 days

The month with the most sunshine days is December (21.8 days).
The month with the least sunshine days is May (10.8 days).

[Resources]

Average UV index in September
Grain Valley, MO

Average UV index in September - Grain Valley, MO
  • Average UV index in September: 5

The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).

[Resources]

Average cloud cover in September
Grain Valley, MO

Average cloud cover in September - Grain Valley, MO
  • Average cloud cover in September: 29

The month with the most cloud cover is March (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 27).

[Resources]

Average visibility in September
Grain Valley, MO

Average visibility in September - Grain Valley, MO
  • 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).

[Resources]

Grain Valley, Missouri, USA

Weather forecast for your location

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