April weather forecastHalf Moon Bay, CA

April
Weather in April
April, like March, is another refreshing spring month in Half Moon Bay, California, with temperature in the range of an average high of 58.6°F (14.8°C) and an average low of 50°F (10°C).Temperature
Half Moon Bay marks the arrival of April with an average high-temperature of a still mild 58.6°F (14.8°C), hardly different from March's 57.7°F (14.3°C). During April, Half Moon Bay perceives a slight decrease in temperature from daytime highs, settling at an average low of 50°F (10°C).Humidity
The average relative humidity in April is 77%.Rainfall
In Half Moon Bay, in April, it is raining for 7.2 days, with typically 0.43" (11mm) of accumulated precipitation. In Half Moon Bay, during the entire year, the rain falls for 76.8 days and collects up to 8.54" (217mm) of precipitation.Daylight
In April, the average length of the day is 13h and 11min.On the first day of the month, sunrise is at 6:53 am and sunset at 7:32 pm. On the last day of April, sunrise is at 6:14 am and sunset at 7:59 pm PDT.
Sunshine
The average sunshine in April is 10h.UV index
The months with the lowest UV index are January through May, July, October through December, with an average maximum UV index of 4. A UV Index reading of 3 to 5 represents a moderate health risk from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The daily maximum UV index of 4 in April interprets into the following advice:
Take care. Persons with lighter skin might suffer burns in less than 30 minutes. Around midday, solar radiation is most harmful; hence, exposure should be limited. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in April
Half Moon Bay, CA
- Average high temperature in April: 58.6°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 April: 50°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 April
Half Moon Bay, CA
- Average pressure in April: 30.04"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 April
Half Moon Bay, CA
- Average wind speed in April: 9.6mph
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 April
Half Moon Bay, CA
- Average humidity in April: 77%
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 April
Half Moon Bay, CA
- Average rainfall in April: 0.43"
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 April
Half Moon Bay, CA
- Average rainfall days in April: 7.2 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 April /
Average sunshine in April
Half Moon Bay, CA
- Average daylight in April: 13h and 12min
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 April: 10h 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 April
Half Moon Bay, CA
- Average sunshine days in April: 22 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 April
Half Moon Bay, CA
- Average UV index in April: 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 April
Half Moon Bay, CA
- Average cloud cover in April: 30
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 April
Half Moon Bay, CA
- Average visibility in April: 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).





