December weather forecast and climate
Riley, KS

December, the first month of the winter, in Riley, is still a cold month, with average temperature fluctuating between 41°F (5°C) and 26.4°F (-3.1°C).

Temperature

In December, the average high-temperature decreases, from a fresh 53.6°F (12°C) in November, to a cold 41°F (5°C). The average low-temperature, in Riley, is 26.4°F (-3.1°C).

Humidity

The average relative humidity is 71%.

Rainfall

In Riley, in December, during 4.4 rainfall days, 0.79" (20mm) of precipitation is typically accumulated. In Riley, Kansas, during the entire year, the rain falls for 114.8 days and collects up to 21.1" (536mm) of precipitation.

Snowfall

Months with snowfall in Riley are January through April, October through December. In Riley, Kansas, in December, snow falls for 3.2 days, with typically accumulated 0.94" (24mm) of snow. In Riley, during the entire year, snow falls for 17.5 days, and aggregates up to 7.32" (186mm) of snow.

Daylight

With an average of 9.4h of daylight, December has the shortest days of the year in Riley.

Sunshine

The month with the least sunshine in Riley is December, with an average of 5.7h of sunshine.

UV index

Months with the lowest UV index in Riley are January, February, November and December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low threat to health from unprotected exposure to the Sun's UV rays for ordinary individuals.
Note: The average daily UV index of 2 transform into the following instructions:
Extended sun exposure is not an issue for the majority. Children, infants, and fair-skinned individuals always need to be protected. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.

What is the temperature in December in Riley?

In December, the average high-temperature is 41°F (5°C), and the average low-temperature is 26.4°F (-3.1°C).

What is the average humidity in December in Riley?

The average relative humidity in December in Riley is 71%.

How many days does it rain in December in Riley?

In Riley, Kansas, in December, it is raining for 4.4 days, with typically 0.79" (20mm) of accumulated precipitation.

How many days does it snow in December in Riley?

In Riley, in December, snow falls for 3.2 days, with typically accumulated 0.94" (24mm) of snow.

What is the month with the shortest days in Riley?

December has the shortest days of the year in Riley, with an average of 9.4h of daylight.

What is the average length of the day in December in Riley?

In Riley, the average length of the day in December is 9.4h.

What is the month with the least sunshine in Riley?

With an average of 5.7h of sunshine, December has the least sunshine of the year in Riley.

How many hours of sunshine does Riley have in December?

The average sunshine in December is 5.7h.

What is the month with the lowest UV index in Riley?

Months with the lowest UV index in Riley, Kansas, are January, February, November and December, with an average maximum UV index of 2.

What is the UV index intensity in December in Riley?

In December, the average daily maximum UV index in Riley, Kansas, is 2. A UV Index reading of 2, and below, represents a minimal hazard to health from the exposure to the Sun's UV radiation.
Average temperature in December - Riley, KS
  • Average high temperature in December: 41°F

The warmest month (with the highest average high temperature) is July (89.6°F).
The month with the lowest average high temperature is January (38.8°F).

  • Average low temperature in December: 26.4°F

The month with the highest average low temperature is July (69.8°F).
The coldest month (with the lowest average low temperature) is January (23°F).

Average pressure in December - Riley, KS
  • Average pressure in December: 30.13"

The month with the highest atmospheric pressure is January (30.16").
The month with the lowest atmospheric pressure is June (29.85").

Average wind speed in December - Riley, KS
  • Average wind speed in December: 10.1mph

The windiest month (with the highest average wind speed) is April (11.8mph).
The calmest month (with the lowest average wind speed) is August (8.6mph).

Average humidity in December - Riley, KS
  • Average humidity in December: 71%

The month with the highest relative humidity is May (74%).
The month with the lowest relative humidity is October (64%).

Average rainfall in December - Riley, KS
  • Average rainfall in December: 0.79"

The wettest month (with the highest rainfall) is May (3.98").
The driest month (with the least rainfall) is January (0.63").

Average rainfall days in December - Riley, KS
  • Average rainfall days in December: 4.4 days

The month with the highest number of rainy days is May (14.3 days).
The month with the least rainy days is January (3.7 days).

Average snowfall in December - Riley, KS
  • Average snowfall in December: 0.94"

The month with the highest snowfall is February (2.24").
Months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in December - Riley, KS
  • Average snowfall days in December: 3.2 days

The month with the highest number of snowfall days is February (4.8 days).
Months with the least snowfall days are May, June, July, August and September (0 days).

Average daylight in December / Average sunshine in December - Riley, KS
  • Average daylight in December: 9.4h

The month with the longest days is June (Average daylight: 14.9h).
The month with the shortest days is December (Average daylight: 9.4h).

  • Average sunshine in December: 5.7h

Months with the most sunshine are June and July (Average sunshine: 10.9h).
The month with the least sunshine is December (Average sunshine: 5.7h).

Average sunshine days in December - Riley, KS
  • Average sunshine days in December: 23.3 days

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

Average UV index in December - Riley, KS
  • Average UV index in December: 2

The month with the highest UV index is June (UV index 7).
Months with the lowest UV index are January, February, November and December (UV index 2).

Average cloud cover in December - Riley, KS
  • Average cloud cover in December: 36

The month with the most cloud cover is March (Cloud cover 41).
The month with the least cloud cover is June (Cloud cover 22).

Average visibility in December - Riley, KS
  • Average visibility in December: 6mi

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