December weather forecastHays, MT
December
Weather in December
December, the first month of the winter in Hays, is still a freezing cold month, with temperature in the range of an average high of 25.9°F (-3.4°C) and an average low of 13.8°F (-10.1°C).Temperature
Onset of December comes with a temperature decline, the average high falling from an icy 39.6°F (4.2°C) in November to a freezing cold 25.9°F (-3.4°C). An average low-temperature of 13.8°F (-10.1°C) is noted during the nights in December.Humidity
In Hays, the average relative humidity in December is 82%.Rainfall
February and December are months with the least rain when the rain falls for 4 days and typically aggregates up to 0.55" (14mm) of rain.Snowfall
January through May, September through December are months with snowfall in Hays. December is the month with the most snowfall in Hays. Snow falls for 12.7 days and accumulates 3.9" (99mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 30min of daylight.On the first day of the month, sunrise is at 7:44 am and sunset at 4:23 pm. On the last day of December, sunrise is at 8:04 am and sunset at 4:31 pm MST.
Sunshine
In December, the average sunshine is 5h.UV index
With an average maximum UV index of 1, December is the month with the lowest UV index in Hays. A UV Index of 2, and less, symbolizes a low health risk from unsafe exposure to UV radiation for the ordinary person.Note: A maximum UV index of 1 in December translates into the following recommendations:
Most individuals face no significant issues with extended sun exposure, but it is always essential to protect children, babies, and those with sensitive skin. The solar radiation around mid-day is intense; avoid the Sun and stay safe. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes. Notice this! Nearly double the intensity of the Sun's UV radiation can be caused by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Hays, MT
- Average high temperature in December: 25.9°F
The warmest month (with the highest average high temperature) is July (83.5°F).
The months with the lowest average high temperature are January and February (25.7°F).
- Average low temperature in December: 13.8°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 (11.8°F).
Average pressure in December
Hays, MT
- Average pressure in December: 30.12"Hg
The month with the highest atmospheric pressure is February (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.83"Hg).
Average wind speed in December
Hays, MT
- Average wind speed in December: 9.1mph
The windiest month (with the highest average wind speed) is April (11.2mph).
The calmest month (with the lowest average wind speed) is February (8.8mph).
Average humidity in December
Hays, MT
- Average humidity in December: 82%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is August (41%).
Average rainfall in December
Hays, MT
- Average rainfall in December: 0.55"
The wettest months (with the highest rainfall) are May and June (1.89").
The driest months (with the least rainfall) are February and December (0.55").
Average rainfall days in December
Hays, MT
- Average rainfall days in December: 4 days
The month with the highest number of rainy days is May (14.1 days).
The month with the least rainy days is December (4 days).
Average snowfall in December
Hays, MT
- Average snowfall in December: 3.9"
The month with the highest snowfall is December (3.9").
The months with the least snowfall are June, July and August (0").
Average snowfall days in December
Hays, MT
- Average snowfall days in December: 12.7 days
The month with the highest number of snowfall days is December (12.7 days).
The months with the least snowfall days are June, July and August (0 days).
Average daylight in December /
Average sunshine in December
Hays, MT
- Average daylight in December: 8h and 30min
The month with the longest days is June (Average daylight: 16h and 0min).
The month with the shortest days is December (Average daylight: 8h and 30min).
- Average sunshine in December: 5h and 0min
The month with the most sunshine is July (Average sunshine: 11h and 48min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in December
Hays, MT
- Average sunshine days in December: 16.7 days
The month with the most sunshine days is September (19.6 days).
The month with the least sunshine days is April (13.4 days).
Average UV index in December
Hays, MT
- Average UV index in December: 1
The month with the highest UV index is July (UV index 7).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Hays, MT
- Average cloud cover in December: 47
The month with the most cloud cover is February (Cloud cover 49).
The months with the least cloud cover are July and August (Cloud cover 17).
Average visibility in December
Hays, MT
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
