December weather forecastNorwalk, CA
December
Weather in December
December completes the annual weather cycle in Norwalk, reverting to colder temperatures typical of the winter season. An average high of no more than 64.6°F (18.1°C) coupled with increased rainfall of 1.46" (37mm) highlights the return of the colder months. With extended cloud cover and increased relative humidity, this month presents more gray days than usual. Despite having the highest rainfall in the year, December retains good visibility, offering clear views of the city's winter landscape. The weather in December, with its bitingly cold winds and frequent rainfall, truly embodies a Californian winter.Temperature
Norwalk's coldest month, December, generally records average temperatures ranging from a high of 64.6°F (18.1°C) to a low of 51.1°F (10.6°C).Humidity
In Norwalk, the average relative humidity in December is 55%.Rainfall
December is the month with the most rainfall. Rain falls for 6.1 days and accumulates 1.46" (37mm) of precipitation.Daylight
With an average of 9h and 54min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 6:39 am and sunset at 4:43 pm. On the last day of the month, sunrise is at 6:57 am and sunset at 4:54 pm PST.
Sunshine
The month with the least sunshine is December, with an average of 6.7h of sunshine.UV index
February, November and December, with an average maximum UV index of 4, are months with the lowest UV index. A UV Index value of 3 to 5 symbolizes a moderate threat to health from unsafe exposure to UV radiation for average individuals.Note: The average daily UV index of 4 in December transforms into the following instructions:
Take precautions. Light skin individuals may get burned in less than 30 minutes. To avoid the Sun's strongest rays, limit exposure around the mid-day period. By wearing a generously brimmed hat, you can cut UV radiation exposure significantly.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Norwalk, CA
- Average high temperature in December: 64.6°F
The warmest month (with the highest average high temperature) is August (83.1°F).
The month with the lowest average high temperature is December (64.6°F).
- Average low temperature in December: 51.1°F
The month with the highest average low temperature is August (65.7°F).
The coldest month (with the lowest average low temperature) is February (50.5°F).
Average pressure in December
Norwalk, CA
- Average pressure in December: 30.07"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The months with the lowest atmospheric pressure are June and September (29.89"Hg).
Average wind speed in December
Norwalk, CA
- Average wind speed in December: 5.3mph
The windiest month (with the highest average wind speed) is April (6.1mph).
The calmest month (with the lowest average wind speed) is October (4.7mph).
Average humidity in December
Norwalk, CA
- Average humidity in December: 55%
The month with the highest relative humidity is June (66%).
The month with the lowest relative humidity is November (51%).
Average rainfall in December
Norwalk, CA
- Average rainfall in December: 1.46"
The wettest month (with the highest rainfall) is December (1.46").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in December
Norwalk, CA
- Average rainfall days in December: 6.1 days
The month with the highest number of rainy days is March (7.1 days).
The month with the least rainy days is June (1.2 days).
Average daylight in December /
Average sunshine in December
Norwalk, CA
- Average daylight in December: 9h and 54min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in December: 6h and 42min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in December
Norwalk, CA
- Average sunshine days in December: 23.4 days
The months with the most sunshine days are January and August (25.6 days).
The month with the least sunshine days is February (21.1 days).
Average UV index in December
Norwalk, CA
- Average UV index in December: 4
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are February, November and December (UV index 4).
Average cloud cover in December
Norwalk, CA
- Average cloud cover in December: 22
The months with the most cloud cover are March and December (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 6).
Average visibility in December
Norwalk, CA
- 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).
