December weather forecastWest Menlo Park, CA
December
Weather in December
December, the first month of the winter in West Menlo Park, is still a refreshing month, with an average temperature fluctuating between 55.8°F (13.2°C) and 47.1°F (8.4°C).Temperature
West Menlo Park's coldest month, December, generally records average temperatures ranging from a high of 55.8°F (13.2°C) to a low of 47.1°F (8.4°C).Humidity
In December, the average relative humidity is 72%.Rainfall
In West Menlo Park, during December, the rain falls for 8.9 days and regularly aggregates up to 0.79" (20mm) of precipitation. Throughout the year, there are 57.5 rainfall days, and 4.76" (121mm) of precipitation is accumulated.Daylight
With an average of 9h and 36min of daylight, December has the shortest days of the year.On the first day of December, sunrise is at 7:05 am and sunset at 4:51 pm. On the last day of the month, sunrise is at 7:23 am and sunset at 5:01 pm PST.
Sunshine
With an average of 5.9h of sunshine, December has the least sunshine of the year.UV index
February, November and December, with an average maximum UV index of 3, are months with the lowest UV index. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: The UV index of 3 during December translates into the following guidance:
Heed the precautions - It is counselled to guard against solar damage. The solar radiation around mid-day is intense; avoid the Sun and stay safe. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
West Menlo Park, CA
- Average high temperature in December: 55.8°F
The warmest month (with the highest average high temperature) is August (73°F).
The month with the lowest average high temperature is December (55.8°F).
- Average low temperature in December: 47.1°F
The months with the highest average low temperature are August and September (56.7°F).
The coldest months (with the lowest average low temperature) are January and February (46.4°F).
Average pressure in December
West Menlo Park, CA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is September (29.92"Hg).
Average wind speed in December
West Menlo Park, CA
- Average wind speed in December: 6.6mph
The windiest month (with the highest average wind speed) is April (7.6mph).
The calmest month (with the lowest average wind speed) is August (5.5mph).
Average humidity in December
West Menlo Park, CA
- Average humidity in December: 72%
The month with the highest relative humidity is March (76%).
The month with the lowest relative humidity is October (68%).
Average rainfall in December
West Menlo Park, CA
- Average rainfall in December: 0.79"
The wettest month (with the highest rainfall) is February (0.98").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in December
West Menlo Park, CA
- Average rainfall days in December: 8.9 days
The month with the highest number of rainy days is March (10.6 days).
The month with the least rainy days is June (0.9 days).
Average daylight in December /
Average sunshine in December
West Menlo Park, CA
- Average daylight in December: 9h and 36min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in December: 5h and 54min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 54min).
Average sunshine days in December
West Menlo Park, CA
- Average sunshine days in December: 20.4 days
The months with the most sunshine days are June and July (26.3 days).
The month with the least sunshine days is March (18.3 days).
Average UV index in December
West Menlo Park, CA
- Average UV index in December: 3
The months with the highest UV index are June, July, August and September (UV index 5).
The months with the lowest UV index are February, November and December (UV index 3).
Average cloud cover in December
West Menlo Park, CA
- Average cloud cover in December: 33
The month with the most cloud cover is March (Cloud cover 35).
The month with the least cloud cover is July (Cloud cover 9).
Average visibility in December
West Menlo Park, 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).





