December weather forecast
Byrnsville, PA

Share

Weather in December

December, the first month of the winter in Byrnsville, is also an icy month, with an average temperature varying between 27.5°F (-2.5°C) and 38.1°F (3.4°C).

Temperature

The commencement of December indicates a shift in the average high-temperature, receding from November's frosty 47.5°F (8.6°C) to an icy 38.1°F (3.4°C). In the month of December, Byrnsville experiences an average low-temperature of 27.5°F (-2.5°C).

Humidity

The average relative humidity in December is 82%.

Rainfall

In December, the rain falls for 11.9 days. Throughout December, 2.28" (58mm) of precipitation is accumulated. Throughout the year, there are 159.6 rainfall days, and 29.41" (747mm) of precipitation is accumulated.

Snowfall

January through May, October through December are months with snowfall. In Byrnsville, in December, snow falls for 8.7 days, with typically accumulated 3.54" (90mm) of snow. In Byrnsville, during the entire year, snow falls for 48.2 days and aggregates up to 24.84" (631mm) of snow.

Daylight

With an average of 9h and 18min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 7:10 am and sunset at 4:38 pm. On the last day of December, sunrise is at 7:29 am and sunset at 4:47 pm EST.

Sunshine

In December, the average sunshine is 4.4h.

UV index

The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for average individuals.
Note: In December, the UV index of 2 transforms into the following advice:
While most people can stay under the sun for an hour without burning, children must always be guarded against sun exposure. Midday is the peak time for the Sun's radiation; stay in the shade and protect yourself. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Be informed! The Sun's UV radiation can be nearly doubled due to the reflection from snow.

Frequently asked questions

How cold is it in December?

The high-temperature, in December, in Byrnsville, records 38.1°F (3.4°C), while the low-temperature is 27.5°F (-2.5°C). The average heat index (a.k.a. 'feels like', 'apparent temperature'), which combines relative humidity and air temperature, in July is evaluated at 86°F (30°C).

What is the average humidity in December?

In December, the average relative humidity in Byrnsville is 82%.

How much does it rain in December?

In Byrnsville, in December, it is raining for 11.9 days, with typically 2.28" (58mm) of accumulated precipitation.

How much does it snow in December?

In Byrnsville, in December, snow falls for 8.7 days, with typically accumulated 3.54" (90mm) of snow.

What is the month with the shortest days?

With an average of 9h and 18min of daylight, December has the shortest days of the year.

What is the average length of the day in December?

In December, the average day length is 9h and 19min.

When are sunrise and sunset in December?

In December, on the first day of the month, sunrise is at 7:10 am and sunset at 4:38 pm. On the last day of the month, sunrise is at 7:29 am and sunset at 4:47 pm EST.

How long on average sun shines in December?

In Byrnsville, the average sunshine duration in December is 4.4h.

What is the month with the lowest UV index?

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

How high is the UV index in December?

In December, the average daily maximum UV index is 2. A UV Index of 2, and less, symbolizes a low health risk from unprotected exposure to 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
Byrnsville, PA

Average temperature in December - Byrnsville, PA
  • Average high temperature in December: 38.1°F

The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (31.8°F).

  • Average low temperature in December: 27.5°F

The month with the highest average low temperature is July (61.3°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).

Average pressure in December
Byrnsville, PA

Average pressure in December - Byrnsville, PA
  • Average pressure in December: 30.09"Hg

The month with the highest atmospheric pressure is November (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).

Average wind speed in December
Byrnsville, PA

Average wind speed in December - Byrnsville, PA
  • Average wind speed in December: 7.6mph

The windiest month (with the highest average wind speed) is March (8.3mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).

Average humidity in December
Byrnsville, PA

Average humidity in December - Byrnsville, PA
  • Average humidity in December: 82%

The month with the highest relative humidity is February (83%).
The month with the lowest relative humidity is April (77%).

Average rainfall in December
Byrnsville, PA

Average rainfall in December - Byrnsville, PA
  • Average rainfall in December: 2.28"

The wettest month (with the highest rainfall) is May (3.11").
The driest month (with the least rainfall) is September (1.77").

Average rainfall days in December
Byrnsville, PA

Average rainfall days in December - Byrnsville, PA
  • Average rainfall days in December: 11.9 days

The month with the highest number of rainy days is May (18.2 days).
The month with the least rainy days is January (8.9 days).

Average snowfall in December
Byrnsville, PA

Average snowfall in December - Byrnsville, PA
  • Average snowfall in December: 3.54"

The month with the highest snowfall is January (5.98").
The months with the least snowfall are June, July, August and September (0").

Average snowfall days in December
Byrnsville, PA

Average snowfall days in December - Byrnsville, PA
  • Average snowfall days in December: 8.7 days

The month with the highest number of snowfall days is January (12.8 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in December /
Average sunshine in December
Byrnsville, PA

Average daylight in December / Average sunshine in December - Byrnsville, PA
  • Average daylight in December: 9h and 2min

The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 18min).

  • Average sunshine in December: 4h and 2min

The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 12min).

Average sunshine days in December
Byrnsville, PA

Average sunshine days in December - Byrnsville, PA
  • Average sunshine days in December: 14.6 days

The month with the most sunshine days is November (16.5 days).
The month with the least sunshine days is February (10.3 days).

Average UV index in December
Byrnsville, PA

Average UV index in December - Byrnsville, PA
  • Average UV index in December: 2

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

Average cloud cover in December
Byrnsville, PA

Average cloud cover in December - Byrnsville, PA
  • Average cloud cover in December: 55

The months with the most cloud cover are February and December (Cloud cover 55).
The month with the least cloud cover is July (Cloud cover 33).

Average visibility in December
Byrnsville, PA

Average visibility in December - Byrnsville, PA
  • Average visibility in December: 5mi

The month with the highest visibility is April (6mi).
The months with the lowest visibility are January, February, March, May, June, July, August, September, October, November and December (5mi).

Byrnsville, Pennsylvania, USA

Weather forecast for your location

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