December weather forecastLetts, IN
December
Weather in December
The first month of the winter, December, is still a cold month in Letts, Indiana, with an average temperature ranging between max 40.6°F (4.8°C) and min 29.5°F (-1.4°C).Temperature
Stepping into December, Letts observes a temperature decline, with the average high falling from November's cool 50.9°F (10.5°C) to an icy 40.6°F (4.8°C). Throughout December nights, Letts experiences a consistent temperature average of 29.5°F (-1.4°C).Humidity
With an average relative humidity of 82%, December is the most humid month.Rainfall
In Letts, in December, during 9.9 rainfall days, 1.26" (32mm) of precipitation is typically accumulated. Throughout the year, there are 137.6 rainfall days, and 17.99" (457mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, October through December. In Letts, in December, snow falls for 6.6 days, with typically accumulated 0.91" (23mm) of snow. Throughout the year, there are 29.3 snowfall days, and 5.35" (136mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 30min of daylight.On the first day of December, sunrise is at 7:43 am and sunset at 5:19 pm. On the last day of the month, sunrise is at 8:01 am and sunset at 5:29 pm EST.
Sunshine
The average sunshine in December is 4.1h.UV index
December is the month with the lowest UV index, with an average maximum UV index of 1. A UV Index of 2, and less, symbolizes a minimal health vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: A maximum high UV index of 1 in December translates into the following recommendations:
While most people can stay under the sun for an hour without burning, children must always be guarded against sun exposure. Minimize direct exposure to the Sun during midday when its radiation is at its peak. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. On your guard! Snow's reflection can almost double the intensity of the Sun's UV radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Letts, IN
- Average high temperature in December: 40.6°F
The warmest month (with the highest average high temperature) is July (83.1°F).
The month with the lowest average high temperature is January (34.9°F).
- Average low temperature in December: 29.5°F
The month with the highest average low temperature is July (65.3°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).
Average pressure in December
Letts, IN
- Average pressure in December: 30.12"Hg
The months with the highest atmospheric pressure are January and November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in December
Letts, IN
- Average wind speed in December: 8.5mph
The windiest months (with the highest average wind speed) are January and February (9.1mph).
The calmest months (with the lowest average wind speed) are July and August (5.4mph).
Average humidity in December
Letts, IN
- Average humidity in December: 82%
The month with the highest relative humidity is December (82%).
The month with the lowest relative humidity is October (74%).
Average rainfall in December
Letts, IN
- Average rainfall in December: 1.26"
The wettest month (with the highest rainfall) is May (2.01").
The driest month (with the least rainfall) is September (0.98").
Average rainfall days in December
Letts, IN
- Average rainfall days in December: 9.9 days
The month with the highest number of rainy days is May (15.4 days).
The month with the least rainy days is February (7.9 days).
Average snowfall in December
Letts, IN
- Average snowfall in December: 0.91"
The month with the highest snowfall is March (1.46").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Letts, IN
- Average snowfall days in December: 6.6 days
The month with the highest number of snowfall days is February (7.3 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Letts, IN
- Average daylight in December: 9h and 30min
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 30min).
- Average sunshine in December: 4h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in December
Letts, IN
- Average sunshine days in December: 16.2 days
The month with the most sunshine days is November (19.5 days).
The month with the least sunshine days is July (12.4 days).
Average UV index in December
Letts, IN
- Average UV index in December: 1
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Letts, IN
- Average cloud cover in December: 56
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is August (Cloud cover 30).
Average visibility in December
Letts, IN
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).





