Expand
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 daylight
- Average sunshine
- Average sunshine days
- Average UV index
- Average cloud cover
- Average visibility
Weather in January
January, like December, in Altadena, California, is another enjoyable winter month, with an average temperature fluctuating between 62.8°F (17.1°C) and 46.4°F (8°C). A minor adjustment in Altadena's average high-temperature is noted with the start of January, touching a still enjoyable 62.8°F (17.1°C) from December's 61°F (16.1°C). Weather in January »
Weather in February
The last month of the winter, February, is another refreshing month in Altadena, California, with an average temperature ranging between max 62.4°F (16.9°C) and min 45.7°F (7.6°C). Upon the beginning of February, Altadena's high-temperatures register at a still comfortable 62.4°F (16.9°C), closely mirroring the preceding month. Weather in February »
Weather in March
The first month of the spring, March, is also an enjoyable month in Altadena, California, with an average temperature varying between 66°F (18.9°C) and 46.9°F (8.3°C). With the onset of March, the average high-temperature stands at a still enjoyable 66°F (18.9°C), closely aligned with February's 62.4°F (16.9°C). Weather in March »
Weather in April
April is a pleasant spring month in Altadena, California, with an average temperature varying between 49.8°F (9.9°C) and 70°F (21.1°C). Altadena observes a minor difference in average high-temperatures between March's 66°F (18.9°C) and April's 70°F (21.1°C). Weather in April »
Weather in May
The last month of the spring, May, is also an agreeable month in Altadena, California, with an average temperature varying between 73.2°F (22.9°C) and 53.2°F (11.8°C). The commencement of May introduces an average high-temperature of a still agreeable 73.2°F (22.9°C), closely mirroring the preceding month. Weather in May »
Weather in June
June, the first month of the summer in Altadena, is a moderately hot month, with an average temperature fluctuating between 79.9°F (26.6°C) and 57.7°F (14.3°C). Altadena's transition into June is marked by a minor temperature shift, moving from a pleasant 73.2°F (22.9°C) in May to a moderately hot 79.9°F (26.6°C). Weather in June »
Weather in July
July, like June, in Altadena, California, is a moderately hot summer month, with temperature in the range of an average low of 63.3°F (17.4°C) and an average high of 85.1°F (29.5°C). The arrival of July brings an average high-temperature of a still warm 85.1°F (29.5°C), subtly diverging from June's 79.9°F (26.6°C). Weather in July »
Weather in August
The last month of the summer, August, is a hot month in Altadena, California, with an average temperature ranging between min 64.4°F (18°C) and max 86.2°F (30.1°C). Altadena registers the highest average temperatures during the month of August, with peaks of 86.2°F (30.1°C) and lows of 64.4°F (18°C). The average heat index in August is estimated at a hot 87.8°F (31°C). Weather in August »
Weather in September
The first month of the autumn, September, is also a moderately hot month in Altadena, California, with temperature in the range of an average low of 62.6°F (17°C) and an average high of 84.6°F (29.2°C). Altadena's average high-temperature marks a warm 84.6°F (29.2°C) with the advent of September, closely mirroring that of the preceding month. Weather in September »
Weather in October
October, the same as September, is a moderately hot autumn month in Altadena, California, with temperature in the range of an average low of 57.9°F (14.4°C) and an average high of 76.8°F (24.9°C). The transition into October is accompanied by a slight temperature decrease, with the average high-temperature shifting from a moderately hot 84.6°F (29.2°C) in September to a still warm 76.8°F (24.9°C). Weather in October »
Weather in November
November, the last month of the autumn in Altadena, is also an agreeable month, with an average temperature fluctuating between 51.1°F (10.6°C) and 68.7°F (20.4°C). The move into November indicates a slight reduction in the average high-temperature, down from October's warm 76.8°F (24.9°C) to an agreeable 68.7°F (20.4°C). Weather in November »
Weather in December
December, the first month of the winter in Altadena, is still a refreshing month, with an average temperature fluctuating between 45.5°F (7.5°C) and 61°F (16.1°C). In Altadena, the month of December registers the lowest temperatures, averaging 61°F (16.1°C) at the peak and 45.5°F (7.5°C) at the lowest. Weather in December »
[Resources]Frequently asked questions
How many days does it rain in Altadena?
In Altadena, during the entire year, the rain falls for 52 days and collects up to 8.82" (224mm) of precipitation.
What is the rainiest month in Altadena?
The month with the most rainfall is February, when the rain falls for 6.1 days and typically aggregates up to 1.81" (46mm) of precipitation.
What is the month with the least sunshine in Altadena?
February and December, with an average of 6.9h of sunshine, are months with the least sunshine.
What are the most humid months in Altadena?
The months with the highest humidity in Altadena are March, May and June, with an average relative humidity of 56%.
When is Daylight Saving Time (DST) in Altadena?
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts in Altadena, 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.
What is the driest month in Altadena?
The month with the least rainfall in Altadena is June, when the rain falls for 1.3 days and typically collects 0.04" (1mm) of precipitation.
When are the longest days in Altadena?
With an average of 14h and 24min of daylight, June has the longest days of the year in Altadena.
What are the months with the most sunshine in Altadena?
June and July, with an average of 12.1h of sunshine, are months with the most sunshine in Altadena.
What is the month with the highest UV index in Altadena?
June through September, with an average maximum UV index of 6, are months with the highest UV index.
What are the warmest months in Altadena?
August brings the highest temperatures, with an average high of 86.2°F (30.1°C) and an average low of 64.4°F (18°C).
What is the least humid month in Altadena?
The least humid month is November, with an average relative humidity of 46%.
What is the coldest time of year in Altadena?
With average high temperatures of 61°F (16.1°C) and lows of 45.5°F (7.5°C), December is the coldest month in Altadena, California.
What is the month with the shortest days in Altadena?
With an average of 9h and 54min of daylight, December has the shortest days of the year in Altadena, California.
What is the month with the lowest UV index in Altadena?
The month with the lowest UV index in Altadena is December, with an average maximum UV index of 3.
Average temperature
Altadena, CA
The warmest month (with the highest average high temperature) is August (86.2°F).
The month with the lowest average high temperature is December (61°F).
The month with the highest average low temperature is August (64.4°F).
The coldest month (with the lowest average low temperature) is December (45.5°F).
Average pressure
Altadena, CA
- Average pressure in January:
30.11"Hg - Average pressure in February:
30.05"Hg - Average pressure in March:
30.03"Hg - Average pressure in April:
29.96"Hg - Average pressure in May:
29.92"Hg - Average pressure in June:
29.88"Hg
- Average pressure in July:
29.91"Hg - Average pressure in August:
29.89"Hg - Average pressure in September:
29.89"Hg - Average pressure in October:
29.95"Hg - Average pressure in November:
30.03"Hg - Average pressure in December:
30.08"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed
Altadena, CA
- Average wind speed in January:
5.5mph - Average wind speed in February:
5.2mph - Average wind speed in March:
5.3mph - Average wind speed in April:
5.8mph - Average wind speed in May:
5.7mph - Average wind speed in June:
5.2mph
- Average wind speed in July:
4.9mph - Average wind speed in August:
4.6mph - Average wind speed in September:
4.4mph - Average wind speed in October:
4.7mph - Average wind speed in November:
5.1mph - Average wind speed in December:
5.5mph
The windiest month (with the highest average wind speed) is April (5.8mph).
The calmest month (with the lowest average wind speed) is September (4.4mph).
Average humidity
Altadena, CA
The months with the highest relative humidity are March, May and June (56%).
The month with the lowest relative humidity is November (46%).
Average rainfall
Altadena, CA
- Average rainfall in January:
1.5" - Average rainfall in February:
1.81" - Average rainfall in March:
1.1" - Average rainfall in April:
0.63" - Average rainfall in May:
0.28" - Average rainfall in June:
0.04"
- Average rainfall in July:
0.28" - Average rainfall in August:
0.16" - Average rainfall in September:
0.16" - Average rainfall in October:
0.24" - Average rainfall in November:
0.87" - Average rainfall in December:
1.77"
The wettest month (with the highest rainfall) is February (1.81").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days
Altadena, CA
- Average rainfall days in January:
5.7 days - Average rainfall days in February:
6.1 days - Average rainfall days in March:
7.5 days - Average rainfall days in April:
5.8 days - Average rainfall days in May:
3.5 days - Average rainfall days in June:
1.3 days
- Average rainfall days in July:
3.9 days - Average rainfall days in August:
2.3 days - Average rainfall days in September:
3 days - Average rainfall days in October:
2.9 days - Average rainfall days in November:
3.8 days - Average rainfall days in December:
6.2 days
The month with the highest number of rainy days is March (7.5 days).
The month with the least rainy days is June (1.3 days).
Average daylight / Average sunshine
Altadena, CA
- Average daylight in January:
10h and 1min - Average daylight in February:
11h and 0min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 1min - Average daylight in May:
14h and 0min - Average daylight in June:
14h and 2min
- Average daylight in July:
14h and 1min - Average daylight in August:
13h and 2min - Average daylight in September:
12h and 2min - Average daylight in October:
11h and 2min - Average daylight in November:
10h and 2min - Average daylight in December:
9h and 5min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in January:
7h and 0min - Average sunshine in February:
6h and 5min - Average sunshine in March:
8h and 5min - Average sunshine in April:
11h and 2min - Average sunshine in May:
11h and 4min - Average sunshine in June:
12h and 1min
- Average sunshine in July:
12h and 1min - Average sunshine in August:
12h and 0min - Average sunshine in September:
10h and 5min - Average sunshine in October:
8h and 4min - Average sunshine in November:
7h and 2min - Average sunshine in December:
6h and 5min
The months with the most sunshine are June and July (Average sunshine: 12h and 6min).
The months with the least sunshine are February and December (Average sunshine: 6h and 54min).
Average sunshine days
Altadena, CA
- Average sunshine days in January:
24.5 days - Average sunshine days in February:
21.3 days - Average sunshine days in March:
22.6 days - Average sunshine days in April:
23.1 days - Average sunshine days in May:
25.4 days - Average sunshine days in June:
27.2 days
- Average sunshine days in July:
24.3 days - Average sunshine days in August:
26.2 days - Average sunshine days in September:
25.6 days - Average sunshine days in October:
26.6 days - Average sunshine days in November:
24.8 days - Average sunshine days in December:
23.5 days
The month with the most sunshine days is June (27.2 days).
The month with the least sunshine days is February (21.3 days).
Average UV index
Altadena, CA
The months with the highest UV index are June, July, August and September (UV index 6).
The month with the lowest UV index is December (UV index 3).
Average cloud cover
Altadena, CA
The month with the most cloud cover is March (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility
Altadena, CA
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).
Altadena, California, USA
Weather forecast for your location
1. Click Locate me button
2. Allow the app to use your location
2. Allow the app to use your location
