December weather forecast
New Castle, CO

Share

Weather in December

December, the first month of the winter in New Castle, is still a freezing cold month, with an average temperature varying between 30.7°F (-0.7°C) and 14.9°F (-9.5°C).

Temperature

Setting in of December comes with a decrease in the average high-temperature, moving from a wintry 42.1°F (5.6°C) in November to a freezing cold 30.7°F (-0.7°C). Throughout December, an average low-temperature of 14.9°F (-9.5°C) is experienced.

Humidity

The average relative humidity in December is 79%.

Rainfall

In New Castle, in December, it is raining for 8.4 days, with typically 1.14" (29mm) of accumulated precipitation. In New Castle, during the entire year, the rain falls for 107.7 days and collects up to 11.89" (302mm) of precipitation.

Snowfall

January through May, October through December are months with snowfall in New Castle. In New Castle, in December, during 11 snowfall days, 7.05" (179mm) of snow is typically accumulated. In New Castle, during the entire year, snow falls for 58.6 days and aggregates up to 36.85" (936mm) of snow.

Daylight

The month with the shortest days in New Castle, Colorado, is December, with an average of 9h and 24min of daylight.
On the first day of the month, sunrise is at 7:12 am and sunset at 4:46 pm. On the last day of December, sunrise is at 7:30 am and sunset at 4:56 pm MST.

Sunshine

The average sunshine in December is 6.4h.

UV index

The months with the lowest UV index in New Castle are January through March, October through December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a low threat to health from unsafe exposure to UV radiation for the ordinary person.
Note: An average maximum UV index of 2 in December leads to these recommendations:
Extended exposure to the sun should always be avoided by children, infants, and those with sensitive skin. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses. Take precaution! The reflection from snow can almost double the UV radiation of the Sun.
Updated: Feb 10, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

How cold is December in New Castle?

New Castle in December has an average high-temperature of 30.7°F (-0.7°C) and an average low-temperature of 14.9°F (-9.5°C).

What is the average humidity in December in New Castle?

In December, the average relative humidity in New Castle is 79%.

How many days does it rain in December in New Castle?

In New Castle, during December, the rain falls for 8.4 days and regularly aggregates up to 1.14" (29mm) of precipitation.

How many days does it snow in December in New Castle?

In New Castle, during December, snow falls for 11 days and regularly aggregates up to 7.05" (179mm) of snow.

What is the month with the shortest days in New Castle?

With an average of 9h and 24min of daylight, December has the shortest days of the year in New Castle.

What is the average length of the day in December in New Castle?

The average day length in December in New Castle is 9h and 26min.

When are sunrise and sunset in December in New Castle?

In December, on the first day of the month, sunrise is at 7:12 am and sunset at 4:46 pm. On the last day of the month, sunrise is at 7:30 am and sunset at 4:56 pm MST.

How many hours of sunshine does New Castle have in December?

The average sunshine duration in December is 6.4h.

What is the month with the lowest UV index in New Castle?

The months with the lowest UV index are January through March, October through December, with an average maximum UV index of 2.

What is the UV index intensity in December in New Castle?

The average daily maximum UV index in December in New Castle, Colorado, is 2. A UV Index reading of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV radiation.
Average humidity
Average rainfall days
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
New Castle, CO

Average temperature in December - New Castle, CO
  • Average high temperature in December: 30.7°F

The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (30.6°F).

  • Average low temperature in December: 14.9°F

The month with the highest average low temperature is July (50.4°F).
The coldest month (with the lowest average low temperature) is January (12°F).

Average pressure in December
New Castle, CO

Average pressure in December - New Castle, CO
  • Average pressure in December: 30.2"Hg

The month with the highest atmospheric pressure is January (30.27"Hg).
The month with the lowest atmospheric pressure is May (29.93"Hg).

Average wind speed in December
New Castle, CO

Average wind speed in December - New Castle, CO
  • Average wind speed in December: 4.2mph

The windiest month (with the highest average wind speed) is June (6.2mph).
The calmest month (with the lowest average wind speed) is January (4.1mph).

Average humidity in December
New Castle, CO

Average humidity in December - New Castle, CO
  • Average humidity in December: 79%

The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is June (43%).

Average rainfall in December
New Castle, CO

Average rainfall in December - New Castle, CO
  • Average rainfall in December: 1.14"

The wettest month (with the highest rainfall) is April (1.57").
The driest month (with the least rainfall) is September (0.51").

Average rainfall days in December
New Castle, CO

Average rainfall days in December - New Castle, CO
  • Average rainfall days in December: 8.4 days

The month with the highest number of rainy days is April (14 days).
The month with the least rainy days is June (5.9 days).

Average snowfall in December
New Castle, CO

Average snowfall in December - New Castle, CO
  • Average snowfall in December: 7.05"

The month with the highest snowfall is February (8.74").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in December
New Castle, CO

Average snowfall days in December - New Castle, CO
  • Average snowfall days in December: 11 days

The month with the highest number of snowfall days is January (13 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in December /
Average sunshine in December
New Castle, CO

Average daylight in December / Average sunshine in December - New Castle, CO
  • Average daylight in December: 9h 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 24min).

  • Average sunshine in December: 6h and 2min

The months with the most sunshine are June, July and August (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 6h and 6min).

Average sunshine days in December
New Castle, CO

Average sunshine days in December - New Castle, CO
  • Average sunshine days in December: 16.9 days

The month with the most sunshine days is June (20.7 days).
The month with the least sunshine days is April (11.7 days).

Average UV index in December
New Castle, CO

Average UV index in December - New Castle, CO
  • Average UV index in December: 2

The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, March, October, November and December (UV index 2).

Average cloud cover in December
New Castle, CO

Average cloud cover in December - New Castle, CO
  • Average cloud cover in December: 34

The month with the most cloud cover is February (Cloud cover 39).
The months with the least cloud cover are June and September (Cloud cover 12).

Average visibility in December
New Castle, CO

Average visibility in December - New Castle, CO
  • Average visibility in December: 5mi

The months with the highest visibility are March, April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is January (4mi).

New Castle, Colorado, USA

Weather forecast for your location

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