December weather forecastRio Vista, TX

December

Weather in December

The first month of the winter, December, is still a refreshing month in Rio Vista, Texas, with an average temperature fluctuating between 56.3°F (13.5°C) and 41°F (5°C).

Temperature

Rio Vista in December experiences a gentle temperature dip, with average high-temperatures reducing from a comfortable 64.9°F (18.3°C) in November to a mild 56.3°F (13.5°C). The nights of December anticipate an average low-temperature of 41°F (5°C).

Humidity

In December, the average relative humidity is 69%.

Rainfall

In Rio Vista, in December, during 9.3 rainfall days, 1.73" (44mm) of precipitation is typically accumulated. In Rio Vista, during the entire year, the rain falls for 135 days and collects up to 29.92" (760mm) of precipitation.

Snowfall

January, April through October and December are months without snowfall.

Daylight

The month with the shortest days is December, with an average of 10h and 6min of daylight.
On the first day of December, sunrise is at 7:13 am and sunset at 5:24 pm. On the last day of the month, sunrise is at 7:30 am and sunset at 5:35 pm CST.

Sunshine

December has the least sunshine of the year, with an average of 5.6h of sunshine.

UV index

January and December, with an average maximum UV index of 3, are months with the lowest UV index. A UV Index value of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for the average person.
Note: The maximum UV index, 3 during December, leads to the following recommendations:
Act with care - Obligation to protect against skin and eye damage is highlighted. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes. Observe! Snow reflection can nearly intensify the Sun's UV radiation twofold.
Updated: Jun 25, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

An average high-temperature, in December, in Rio Vista, is 56.3°F (13.5°C) and the average low-temperature is 41°F (5°C). The average heat index (a.k.a. 'felt air temperature', 'feels like'), which factors the actual air temperature with the relative humidity, in September is computed to be 95°F (35°C).

In December, the average relative humidity is 69%.

In Rio Vista, in December, it is raining for 9.3 days, with typically 1.73" (44mm) of accumulated precipitation.

January, April through October and December are months without snowfall.

In December, in Rio Vista, it doesn't snow. November is the latest month when it typically snows.

With an average of 10h and 6min of daylight, December has the shortest days of the year.

In December, the average day length is 10h and 5min.

On the first day of December, sunrise is at 7:13 am and sunset at 5:24 pm. On the last day of the month, sunrise is at 7:30 am and sunset at 5:35 pm CST.

With an average of 5.6h of sunshine, December has the least sunshine of the year.

In Rio Vista, the average sunshine duration in December is 5.6h.

The months with the lowest UV index are January and December, with an average maximum UV index of 3.

The average daily maximum UV index in December in Rio Vista is 3. A UV Index reading of 3 to 5 represents a medium hazard to health from unsafe exposure to Sun's UV rays.
Average high temperature
Average low temperature
Average pressure
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average snowfall
Average snowfall days
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Rio Vista, TX

  • Average high temperature in December: 56.3°F

The warmest month (with the highest average high temperature) is August (95.5°F).
The month with the lowest average high temperature is January (55.8°F).

  • Average low temperature in December: 41°F

The month with the highest average low temperature is August (75.6°F).
The coldest month (with the lowest average low temperature) is January (39°F).

Average pressure in December
Rio Vista, TX

  • Average pressure in December: 30.12"Hg

The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).

Average wind speed in December
Rio Vista, TX

  • Average wind speed in December: 9mph

The windiest months (with the highest average wind speed) are March and April (10.6mph).
The calmest month (with the lowest average wind speed) is September (6.8mph).

Average humidity in December
Rio Vista, TX

  • Average humidity in December: 69%

The month with the highest relative humidity is May (74%).
The month with the lowest relative humidity is August (57%).

Average rainfall in December
Rio Vista, TX

  • Average rainfall in December: 1.73"

The wettest month (with the highest rainfall) is October (4.21").
The driest month (with the least rainfall) is February (1.5").

Average rainfall days in December
Rio Vista, TX

  • Average rainfall days in December: 9.3 days

The month with the highest number of rainy days is May (15.4 days).
The month with the least rainy days is January (6.1 days).

Average snowfall in December
Rio Vista, TX

  • Average snowfall in December: 0"

The month with the highest snowfall is February (0.94").
The months with the least snowfall are January, April, May, June, July, August, September, October and December (0").

Average snowfall days in December
Rio Vista, TX

  • Average snowfall days in December: 0.4 days

The month with the highest number of snowfall days is February (1.3 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).

Average daylight in December /
Average sunshine in December
Rio Vista, TX

  • Average daylight in December: 10h and 6min

The month with the longest days is June (Average daylight: 14h and 12min).
The month with the shortest days is December (Average daylight: 10h and 6min).

  • Average sunshine in December: 5h and 36min

The month with the most sunshine is July (Average sunshine: 11h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 36min).

Average sunshine days in December
Rio Vista, TX

  • Average sunshine days in December: 20.3 days

The month with the most sunshine days is January (23.8 days).
The month with the least sunshine days is May (13.4 days).

Average UV index in December
Rio Vista, TX

  • Average UV index in December: 3

The month with the highest UV index is July (UV index 8).
The months with the lowest UV index are January and December (UV index 3).

Average cloud cover in December
Rio Vista, TX

  • Average cloud cover in December: 36

The month with the most cloud cover is March (Cloud cover 39).
The month with the least cloud cover is August (Cloud cover 21).

Average visibility in December
Rio Vista, TX

  • Average visibility in December: 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).