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Contents
- Weather in January
- Weather in February
- Weather in March
- Weather in April
- Weather in May
- Weather in June
- Weather in July
- Weather in August
- Weather in September
- Weather in October
- Weather in November
- Weather in December
- Frequently asked questions
- Average temperature
- Average pressure
- Average wind speed
- Average humidity
- Average rainfall
- Average rainfall days
- Average snowfall
- Average snowfall days
- Average daylight
- Average sunshine
- Average sunshine days
- Average UV index
- Average cloud cover
- Average visibility
Weather in January
January, like December, in Portola, California, is a wintry winter month, with an average temperature varying between 38.8°F (3.8°C) and 23.2°F (-4.9°C). January's presence records an average high-temperature of a still icy 38.8°F (3.8°C), closely mirroring December's climate. Weather in January »
Weather in February
The last month of the winter, February, is another cold month in Portola, California, with an average temperature varying between 39.6°F (4.2°C) and 22.8°F (-5.1°C). With the onset of February, the average high-temperature stands at a still icy 39.6°F (4.2°C), closely aligned with January's 38.8°F (3.8°C). Weather in February »
Weather in March
March, the first month of the spring in Portola, is a frosty month, with an average temperature varying between 43.2°F (6.2°C) and 25.3°F (-3.7°C). With the transition into March, Portola notes an average high-temperature of a chilly 43.2°F (6.2°C), closely resembling February. Weather in March »
Weather in April
April in Portola, California, is a cool spring month, with an average temperature varying between 51.4°F (10.8°C) and 29.7°F (-1.3°C). April introduces a marginal temperature uplift, with average high-temperatures adjusting from March's frosty 43.2°F (6.2°C) to a fresh 51.4°F (10.8°C). Weather in April »
Weather in May
The last month of the spring, May, is a refreshing month in Portola, California, with temperature in the range of an average low of 35.8°F (2.1°C) and an average high of 60.6°F (15.9°C). 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). Weather in May »
Weather in June
The first month of the summer, June, is an agreeable month in Portola, California, with temperature in the range of an average low of 42.1°F (5.6°C) and an average high of 72.7°F (22.6°C). June's onset brings a rise in the average high-temperature, moving from a moderate 60.6°F (15.9°C) in May to a pleasant 72.7°F (22.6°C). Weather in June »
Weather in July
July in Portola, California, is a warm summer month, with temperature in the range of an average low of 47.5°F (8.6°C) and an average high of 82.9°F (28.3°C). July, having an average high-temperature of 82.9°F (28.3°C) and an average low-temperature of 47.5°F (8.6°C), is the warmest month. July's average heat index is computed to be 82.4°F (28°C). Weather in July »
Weather in August
August, the last month of the summer in Portola, is also a moderately hot month, with an average temperature varying between 46°F (7.8°C) and 81.1°F (27.3°C). The transition into August notes an average high-temperature of a still warm 81.1°F (27.3°C), revealing a mild distinction from the 82.9°F (28.3°C) in July. Weather in August »
Weather in September
September, the first month of the autumn in Portola, is also a moderately hot month, with an average temperature fluctuating between 73.8°F (23.2°C) and 42.3°F (5.7°C). The move into September indicates a slight reduction in the average high-temperature, down from August's warm 81.1°F (27.3°C) to a still moderately hot 73.8°F (23.2°C). Weather in September »
Weather in October
October, the same as September, in Portola, California, is another mild autumn month, with an average temperature ranging between max 60.4°F (15.8°C) and min 34.9°F (1.6°C). The shift from September to October corresponds with a decrease in the average high-temperature, down to a refreshing 60.4°F (15.8°C) from a warm 73.8°F (23.2°C). Weather in October »
Weather in November
November, the last month of the autumn in Portola, is another chilly month, with an average temperature ranging between min 27°F (-2.8°C) and max 47.3°F (8.5°C). Portola's weather changes with the onset of November, slightly falling from a mild 60.4°F (15.8°C) in October to a chilly 47.3°F (8.5°C). Weather in November »
Weather in December
December, the first month of the winter in Portola, is also an icy month, with temperature in the range of an average low of 21.6°F (-5.8°C) and an average high of 37.2°F (2.9°C). Portola's temperature records reveal December as the coldest month, marked by average highs of 37.2°F (2.9°C) and lows of 21.6°F (-5.8°C). Weather in December »
Updated: Jul 9, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the most humid months in Portola?
The months with the highest humidity are January and March, with an average relative humidity of 81%.
How many days does it rain?
Throughout the year, in Portola, there are 80.1 rainfall days, and 22.95" (583mm) of precipitation is accumulated.
When does it snow?
Months with snowfall are January through June, September through December.
How much does it snow?
Throughout the year, there are 69.3 snowfall days, and 103.5" (2629mm) of snow is accumulated.
What is the month with the least sunshine?
With an average of 5h of sunshine, January has the least sunshine of the year.
What is the rainiest month?
The month with the most rainfall is March, when the rain falls for 10.1 days and typically aggregates up to 4.02" (102mm) of precipitation.
When is Daylight Saving Time (DST)?
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Portola, and the time zone changes from PST to PDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from PDT to PST.
When are the longest days?
With an average of 14h and 54min of daylight, June has the longest days of the year.
What are the months with the highest UV index?
The months with the highest UV index are June through August, with an average maximum UV index of 5.
What is the hottest time of year in Portola?
July stands out as Portola's warmest month, with an average high-temperature of 82.9°F (28.3°C) and a low-temperature of 47.5°F (8.6°C).
What is the least humid month?
The months with the lowest humidity in Portola are July and August, with an average relative humidity of 40%.
When it does not snow?
July and August are months without snowfall.
What month has the most sunshine?
July has the most sunshine of the year, with an average of 12h of sunshine.
What is the driest month?
The month with the least rainfall is August, when the rain falls for 3.4 days and typically collects 0.2" (5mm) of precipitation.
When is the lowest UV index?
With an average maximum UV index of 1, November is the month with the lowest UV index.
What is the coldest month?
Portola's coldest month, December, generally records average temperatures ranging from a high of 37.2°F (2.9°C) to a low of 21.6°F (-5.8°C).
When does it snow the most?
December is the month with the most snowfall. Snow falls for 12.8 days and accumulates 22.52" (572mm) of snow.
What is the month with the shortest days?
The month with the shortest days is December, with an average of 9h and 24min of daylight.
Average temperature
Portola, CA
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).
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
Portola, CA
- Average pressure in January:
30.19"Hg - Average pressure in February:
30.09"Hg - Average pressure in March:
30.05"Hg - Average pressure in April:
30"Hg - Average pressure in May:
29.93"Hg - Average pressure in June:
29.9"Hg
- Average pressure in July:
29.92"Hg - Average pressure in August:
29.91"Hg - Average pressure in September:
29.93"Hg - Average pressure in October:
30.02"Hg - Average pressure in November:
30.1"Hg - Average pressure in December:
30.16"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
Portola, CA
- Average wind speed in January:
5.7mph - Average wind speed in February:
6.2mph - Average wind speed in March:
6.6mph - Average wind speed in April:
6.4mph - Average wind speed in May:
6.1mph - Average wind speed in June:
5.9mph
- Average wind speed in July:
5.3mph - Average wind speed in August:
5.2mph - Average wind speed in September:
5.2mph - Average wind speed in October:
5.5mph - Average wind speed in November:
5.5mph - Average wind speed in December:
5.7mph
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
Portola, CA
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
Portola, CA
- Average rainfall in January:
3.62" - Average rainfall in February:
3.58" - Average rainfall in March:
4.02" - Average rainfall in April:
1.97" - Average rainfall in May:
2.05" - Average rainfall in June:
0.43"
- Average rainfall in July:
0.24" - Average rainfall in August:
0.2" - Average rainfall in September:
0.43" - Average rainfall in October:
0.91" - Average rainfall in November:
1.85" - Average rainfall in December:
3.66"
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
Portola, CA
- Average rainfall days in January:
6.8 days - Average rainfall days in February:
6.3 days - Average rainfall days in March:
10.1 days - Average rainfall days in April:
10.6 days - Average rainfall days in May:
11.8 days - Average rainfall days in June:
5.3 days
- Average rainfall days in July:
3.3 days - Average rainfall days in August:
3.4 days - Average rainfall days in September:
4.5 days - Average rainfall days in October:
5 days - Average rainfall days in November:
6.2 days - Average rainfall days in December:
6.8 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
Portola, CA
- Average snowfall in January:
19.09" - Average snowfall in February:
18.46" - Average snowfall in March:
22.48" - Average snowfall in April:
8.58" - Average snowfall in May:
2.76" - Average snowfall in June:
0.28"
The month with the highest snowfall is December (22.52").
The months with the least snowfall are July and August (0").
Average snowfall days
Portola, CA
- Average snowfall days in January:
10.5 days - Average snowfall days in February:
11.4 days - Average snowfall days in March:
14.7 days - Average snowfall days in April:
8.1 days - Average snowfall days in May:
2.8 days - Average snowfall days in June:
0.5 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0.4 days - Average snowfall days in October:
1.2 days - Average snowfall days in November:
6.9 days - Average snowfall days in December:
12.8 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 / Average sunshine
Portola, CA
- Average daylight in January:
9h and 4min - Average daylight in February:
10h and 4min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 2min - Average daylight in May:
14h and 2min - Average daylight in June:
14h and 5min
- Average daylight in July:
14h and 4min - Average daylight in August:
13h and 4min - Average daylight in September:
12h and 2min - Average daylight in October:
11h and 1min - Average daylight in November:
10h and 0min - Average daylight in December:
9h 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 January:
5h - Average sunshine in February:
5h and 4min - Average sunshine in March:
7h - Average sunshine in April:
9h and 4min - Average sunshine in May:
10h and 4min - Average sunshine in June:
11h and 4min
- Average sunshine in July:
12h - Average sunshine in August:
11h and 5min - Average sunshine in September:
11h - Average sunshine in October:
7h and 1min - Average sunshine in November:
6h and 2min - Average sunshine in December:
5h and 1min
The month with the most sunshine is July (Average sunshine: 12h).
The month with the least sunshine is January (Average sunshine: 5h).
Average sunshine days
Portola, CA
- Average sunshine days in January:
16.8 days - Average sunshine days in February:
15 days - Average sunshine days in March:
11.8 days - Average sunshine days in April:
13.3 days - Average sunshine days in May:
16.6 days - Average sunshine days in June:
23.7 days
- Average sunshine days in July:
25.8 days - Average sunshine days in August:
26 days - Average sunshine days in September:
25 days - Average sunshine days in October:
24.8 days - Average sunshine days in November:
19.1 days - Average sunshine days in December:
15.5 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
Portola, CA
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
Portola, CA
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
Portola, CA
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
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