September weather forecast
Ralph, SD

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Weather in September

The first month of the autumn, September, is also an agreeable month in Ralph, South Dakota, with an average temperature fluctuating between 73°F (22.8°C) and 53.4°F (11.9°C).

Temperature

Stepping into September, Ralph observes a temperature decline, with the average high falling from August's moderately hot 82.4°F (28°C) to a pleasant 73°F (22.8°C). Nighttime temperature lowers to an average of 53.4°F (11.9°C) in September.

Humidity

In September, the average relative humidity is 51%.

Rainfall

In September, the rain falls for 8.1 days. Throughout September, 1.14" (29mm) of precipitation is accumulated. Throughout the year, there are 104.8 rainfall days, and 15.2" (386mm) of precipitation is accumulated.

Snowfall

July through September are months without snowfall.

Daylight

In September, the average length of the day in Ralph is 12h and 31min.
On the first day of September, sunrise is at 6:14 am and sunset at 7:29 pm. On the last day of the month, sunrise is at 6:50 am and sunset at 6:33 pm MDT.

Sunshine

The average sunshine in September is 9.7h.

UV index

In Ralph, the average daily maximum UV index in September is 4. A UV Index of 3 to 5 symbolizes a medium vulnerability from unsafe exposure to UV radiation for the ordinary person.
Note: The daily high UV index of 4 in September translates into this advice:
Be cautious. Those with fair skin can be subjected to burns in fewer than 30 minutes. The Sun's most harmful UV rays are emitted around midday; avoid staying outdoors for long during this time. Your best bet for sun defense on the face, eyes, and neck is a hat with a wide brim. Take heed! The reflection of snow can intensify the Sun's UV radiation nearly double.
Updated: Jun 30, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the temperature in September?

September temperatures in Ralph vary between a high-temperature of 73°F (22.8°C) and a low-temperature of 53.4°F (11.9°C). In August, the average heat index (a.k.a. 'real feel', 'apparent temperature'), which combines relative humidity and air temperature, is appraised at 82.4°F (28°C).

What is the average humidity in September?

The average relative humidity in September is 51%.

How many days does it rain in September?

In September, the rain falls for 8.1 days. Throughout September, 1.14" (29mm) of precipitation is accumulated.

When it does not snow in Ralph?

July through September are months without snowfall in Ralph.

Does it snow in September?

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

How many hours of daylight does Ralph have in September?

In September, the average day length in Ralph is 12h and 31min.

What time are sunrise and sunset in September?

In September, on the first day of the month, sunrise is at 6:14 am and sunset at 7:29 pm. On the last day of the month, sunrise is at 6:50 am and sunset at 6:33 pm MDT.

How many hours of sunshine does Ralph have in September?

In September, the average sunshine duration is 9.7h.

How high is the UV index in September?

In September, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a moderate vulnerability from exposure to the Sun's 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
Ralph, SD

Average temperature in September - Ralph, SD
  • Average high temperature in September: 73°F

The warmest month (with the highest average high temperature) is July (84.7°F).
The month with the lowest average high temperature is January (25.5°F).

  • Average low temperature in September: 53.4°F

The month with the highest average low temperature is July (62.4°F).
The coldest month (with the lowest average low temperature) is January (12°F).

Average pressure in September
Ralph, SD

Average pressure in September - Ralph, SD
  • Average pressure in September: 29.93"Hg

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

Average wind speed in September
Ralph, SD

Average wind speed in September - Ralph, SD
  • Average wind speed in September: 10.7mph

The windiest months (with the highest average wind speed) are January and October (11.7mph).
The calmest month (with the lowest average wind speed) is August (9.7mph).

Average humidity in September
Ralph, SD

Average humidity in September - Ralph, SD
  • Average humidity in September: 51%

The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is August (50%).

Average rainfall in September
Ralph, SD

Average rainfall in September - Ralph, SD
  • Average rainfall in September: 1.14"

The wettest month (with the highest rainfall) is May (2.48").
The driest months (with the least rainfall) are January and November (0.51").

Average rainfall days in September
Ralph, SD

Average rainfall days in September - Ralph, SD
  • Average rainfall days in September: 8.1 days

The month with the highest number of rainy days is May (15.3 days).
The month with the least rainy days is November (3 days).

Average snowfall in September
Ralph, SD

Average snowfall in September - Ralph, SD
  • Average snowfall in September: 0"

The month with the highest snowfall is February (4.84").
The months with the least snowfall are July, August and September (0").

Average snowfall days in September
Ralph, SD

Average snowfall days in September - Ralph, SD
  • Average snowfall days in September: 0.1 days

The month with the highest number of snowfall days is February (13.5 days).
The months with the least snowfall days are July and August (0 days).

Average daylight in September /
Average sunshine in September
Ralph, SD

Average daylight in September / Average sunshine in September - Ralph, SD
  • Average daylight in September: 12h and 3min

The month with the longest days is June (Average daylight: 15h and 42min).
The month with the shortest days is December (Average daylight: 8h and 42min).

  • Average sunshine in September: 9h and 4min

The month with the most sunshine is July (Average sunshine: 11h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 36min).

Average sunshine days in September
Ralph, SD

Average sunshine days in September - Ralph, SD
  • Average sunshine days in September: 19 days

The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is April (11.8 days).

Average UV index in September
Ralph, SD

Average UV index in September - Ralph, SD
  • Average UV index in September: 4

The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is November (UV index 1).

Average cloud cover in September
Ralph, SD

Average cloud cover in September - Ralph, SD
  • Average cloud cover in September: 23

The months with the most cloud cover are January and February (Cloud cover 52).
The months with the least cloud cover are July and August (Cloud cover 20).

Average visibility in September
Ralph, SD

Average visibility in September - Ralph, SD
  • 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).

Ralph, South Dakota, USA

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