Contents
- Weather in January
- Frequently asked questions
- Average temperature in January
- Average pressure in January
- Average wind speed in January
- Average humidity in January
- Average rainfall in January
- Average rainfall days in January
- Average daylight in January
- Average sunshine in January
- Average sunshine days in January
- Average UV index in January
- Average cloud cover in January
- Average visibility in January
Weather in January
Temperature
As December turns into January, the average high-temperatures rest at a still mild 56.1°F (13.4°C), showing a minor variation from the prior month. Half Moon Bay documents an average low-temperature of 49.1°F (9.5°C) for the nights of January.Humidity
The average relative humidity in January in Half Moon Bay, California, is 74%.Rainfall
In January, in Half Moon Bay, the rain falls for 9.2 days. Throughout January, 1.22" (31mm) of precipitation is accumulated. Throughout the year, in Half Moon Bay, there are 76.8 rainfall days, and 8.54" (217mm) of precipitation is accumulated.Daylight
In Half Moon Bay, the average length of the day in January is 9h and 56min.On the first day of the month, sunrise is at 7:24 am and sunset at 5:02 pm. On the last day of January, in Half Moon Bay, sunrise is at 7:13 am and sunset at 5:32 pm PST.
Sunshine
The average sunshine in January is 6h.UV index
The months with the lowest UV index in Half Moon Bay, California, are January through May, July, October through December, with an average maximum UV index of 4. A UV Index value of 3 to 5 symbolizes a medium vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The UV index of 4 during January translates into the following guidance:
Act with care - Obligation to protect against skin and eye damage is highlighted. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. Employ a wide-brim hat for potent defense against up to 50% of UV rays.
Frequently asked questions
What is the average January temperature in Half Moon Bay?
What is the average humidity in January in Half Moon Bay?
How much does it rain in Half Moon Bay in January?
What is the average length of the day in January in Half Moon Bay?
When are sunrise and sunset in January in Half Moon Bay?
How many hours of sunshine does Half Moon Bay have in January?
What is the month with the lowest UV index in Half Moon Bay?
What is the UV index intensity in January in Half Moon Bay?
Average temperature in January
Half Moon Bay, CA
- Average high temperature in January: 56.1°F
The warmest month (with the highest average high temperature) is September (66.9°F).
The month with the lowest average high temperature is December (55.6°F).
- Average low temperature in January: 49.1°F
The month with the highest average low temperature is September (56.7°F).
The coldest month (with the lowest average low temperature) is February (48.7°F).
Average pressure in January
Half Moon Bay, CA
- Average pressure in January: 30.13"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 January
Half Moon Bay, CA
- Average wind speed in January: 7.5mph
The windiest month (with the highest average wind speed) is April (9.6mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in January
Half Moon Bay, CA
- Average humidity in January: 74%
The month with the highest relative humidity is August (82%).
The months with the lowest relative humidity are November and December (72%).
Average rainfall in January
Half Moon Bay, CA
- Average rainfall in January: 1.22"
The wettest month (with the highest rainfall) is February (1.61").
The driest months (with the least rainfall) are June and July (0.12").
Average rainfall days in January
Half Moon Bay, CA
- Average rainfall days in January: 9.2 days
The month with the highest number of rainy days is March (10.8 days).
The month with the least rainy days is June (3 days).
Average daylight in January /
Average sunshine in January
Half Moon Bay, CA
- Average daylight in January: 9h and 5min
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 January: 6h and 0min
The month with the most sunshine is July (Average sunshine: 11h and 24min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).
Average sunshine days in January
Half Moon Bay, CA
- Average sunshine days in January: 20.8 days
The month with the most sunshine days is October (24.6 days).
The months with the least sunshine days are March and August (18.8 days).
Average UV index in January
Half Moon Bay, CA
- Average UV index in January: 4
The months with the highest UV index are June, August and September (UV index 5).
The months with the lowest UV index are January, February, March, April, May, July, October, November and December (UV index 4).
Average cloud cover in January
Half Moon Bay, CA
- Average cloud cover in January: 34
The month with the most cloud cover is March (Cloud cover 38).
The month with the least cloud cover is September (Cloud cover 18).
Average visibility in January
Half Moon Bay, CA
- Average visibility in January: 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).
Half Moon Bay, California, USA
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