Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
The average high-temperature increases in May, moving from a cool 51.4°F (10.8°C) in April to a moderate 60.6°F (15.9°C). Portola's temperature exhibits a stark contrast from daytime to nighttime, averaging lows of 35.8°F (2.1°C) in May.Humidity
In Portola, the average relative humidity in May is 62%.Rainfall
In May, the rain falls for 11.8 days. Throughout May, 2.05" (52mm) of precipitation is accumulated. In Portola, during the entire year, the rain falls for 80.1 days and collects up to 22.95" (583mm) of precipitation.Snowfall
January through June, September through December are months with snowfall. In Portola, in May, during 2.8 snowfall days, 2.76" (70mm) of snow is typically accumulated. In Portola, during the entire year, snow falls for 69.3 days and aggregates up to 103.5" (2629mm) of snow.Daylight
The average length of the day in May is 14h and 23min.On the first day of May, sunrise is at 6:01 am and sunset at 7:56 pm. On the last day of the month, sunrise is at 5:35 am and sunset at 8:23 pm PDT.
Sunshine
In May, the average sunshine is 10.6h.UV index
In Portola, the average daily maximum UV index in May is 4. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for average individuals.Note: The daily maximum UV index of 4 in May interprets into the following advice:
Take care. Persons with lighter skin might suffer burns in less than 30 minutes. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Be alert to the fact! The reflection from snow can nearly double the UV radiation of the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in May?
What is the average humidity in May?
How much does it rain in May?
How many days does it snow in May?
How many hours of daylight does Portola have in May?
What time are sunrise and sunset in May?
How long on average sun shines in May?
What is the UV index reading in May?
Average temperature in May
Portola, CA
- Average high temperature in May: 60.6°F
The warmest month (with the highest average high temperature) is July (82.9°F).
The month with the lowest average high temperature is December (37.2°F).
- Average low temperature in May: 35.8°F
The month with the highest average low temperature is July (47.5°F).
The coldest month (with the lowest average low temperature) is December (21.6°F).
Average pressure in May
Portola, CA
- Average pressure in May: 29.93"Hg
The month with the highest atmospheric pressure is January (30.19"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in May
Portola, CA
- Average wind speed in May: 6.1mph
The windiest month (with the highest average wind speed) is March (6.6mph).
The calmest months (with the lowest average wind speed) are August and September (5.2mph).
Average humidity in May
Portola, CA
- Average humidity in May: 62%
The months with the highest relative humidity are January and March (81%).
The months with the lowest relative humidity are July and August (40%).
Average rainfall in May
Portola, CA
- Average rainfall in May: 2.05"
The wettest month (with the highest rainfall) is March (4.02").
The driest month (with the least rainfall) is August (0.2").
Average rainfall days in May
Portola, CA
- Average rainfall days in May: 11.8 days
The month with the highest number of rainy days is May (11.8 days).
The month with the least rainy days is July (3.3 days).
Average snowfall in May
Portola, CA
- Average snowfall in May: 2.76"
The month with the highest snowfall is December (22.52").
The months with the least snowfall are July and August (0").
Average snowfall days in May
Portola, CA
- Average snowfall days in May: 2.8 days
The month with the highest number of snowfall days is March (14.7 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in May /
Average sunshine in May
Portola, CA
- Average daylight in May: 14h and 2min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in May: 10h and 4min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 5h and 0min).
Average sunshine days in May
Portola, CA
- Average sunshine days in May: 16.6 days
The month with the most sunshine days is August (26 days).
The month with the least sunshine days is March (11.8 days).
Average UV index in May
Portola, CA
- Average UV index in May: 4
The months with the highest UV index are June, July and August (UV index 5).
The month with the lowest UV index is November (UV index 1).
Average cloud cover in May
Portola, CA
- Average cloud cover in May: 28
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 7).
Average visibility in May
Portola, CA
- Average visibility in May: 6mi
The months with the highest visibility are May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (4mi).
Portola, California, USA
Weather forecast for your location
2. Allow the app to use your location