Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
The arrival of December indicates a decrease in the average high-temperature, moving from a chilly 49.1°F (9.5°C) in November to a cold 35.2°F (1.8°C). In December, the temperature drops to an average of 22.8°F (-5.1°C) at night.Humidity
In Siam, the average relative humidity in December is 78%.Rainfall
In Siam, Iowa, during December, the rain falls for 4.3 days and regularly aggregates up to 0.59" (15mm) of precipitation. Throughout the year, there are 114.9 rainfall days, and 18.39" (467mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through April, October through December. In December, it is snowing for 4.5 days. Throughout December, 0.91" (23mm) of snow is accumulated. Throughout the year, there are 25.2 snowfall days, and 7.4" (188mm) of snow is accumulated.Daylight
December has the shortest days of the year in Siam, with an average of 9h and 18min of daylight.On the first day of the month, sunrise is at 7:24 am and sunset at 4:53 pm. On the last day of December, sunrise is at 7:43 am and sunset at 5:02 pm CST.
Sunshine
In December, the average sunshine is 5h.UV index
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index in Siam. A UV Index value of 2, and less, symbolizes a low threat to health from unsafe exposure to UV radiation for the average person.Note: The daily high UV index of 2 in December translates into this advice:
While sun exposure does not greatly affect most, individuals with fair skin, babies, and children always need vigilant safeguarding. Direct Sun exposure should be minimized especially during midday when radiation is most intense. Sun protection is enhanced with clothing that boasts a tight weave yet offers a loose fit. Foresee this! The reflection from snow can nearly double the intensity of UV radiation from the Sun.
Frequently asked questions
How cold is it in Siam in December?
What is the average humidity in December in Siam?
How many days does it rain in December in Siam?
How much does it snow in Siam in December?
What is the month with the shortest days in Siam?
What is the average length of the day in December in Siam?
What time are sunrise and sunset in December in Siam?
How long on average sun shines in December in Siam?
What is the month with the lowest UV index in Siam?
What is the UV index reading in December in Siam?
Average temperature in December
Siam, IA
- Average high temperature in December: 35.2°F
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (31.1°F).
- Average low temperature in December: 22.8°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (17.2°F).
Average pressure in December
Siam, IA
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in December
Siam, IA
- Average wind speed in December: 9.5mph
The windiest month (with the highest average wind speed) is March (10.3mph).
The calmest month (with the lowest average wind speed) is July (6.7mph).
Average humidity in December
Siam, IA
- Average humidity in December: 78%
The month with the highest relative humidity is January (80%).
The month with the lowest relative humidity is October (69%).
Average rainfall in December
Siam, IA
- Average rainfall in December: 0.59"
The wettest month (with the highest rainfall) is June (3.39").
The driest month (with the least rainfall) is February (0.43").
Average rainfall days in December
Siam, IA
- Average rainfall days in December: 4.3 days
The month with the highest number of rainy days is May (16.7 days).
The month with the least rainy days is February (3.4 days).
Average snowfall in December
Siam, IA
- Average snowfall in December: 0.91"
The month with the highest snowfall is January (2.17").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in December
Siam, IA
- Average snowfall days in December: 4.5 days
The month with the highest number of snowfall days is January (7.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Siam, IA
- Average daylight in December: 9h and 2min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in December: 5h and 0min
The month with the most sunshine is July (Average sunshine: 10h and 24min).
The month with the least sunshine is January (Average sunshine: 4h and 36min).
Average sunshine days in December
Siam, IA
- Average sunshine days in December: 22 days
The month with the most sunshine days is November (22.5 days).
The month with the least sunshine days is June (12.3 days).
Average UV index in December
Siam, IA
- Average UV index in December: 2
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Siam, IA
- Average cloud cover in December: 45
The month with the most cloud cover is January (Cloud cover 49).
The month with the least cloud cover is July (Cloud cover 27).
Average visibility in December
Siam, IA
- 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).
Siam, Iowa, USA
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