Nestled just northeast of downtown Los Angeles, Pasadena, California, is a city known for its pleasant and varied climate.
The city of Pasadena enjoys a Mediterranean climate, specifically classified in the Köppen climate classification as a Csb zone. This means mild, wet winters and hot, dry summers.
Pasadena experiences the hot season from late June to late September, with August recording the highest temperatures, averaging an 88°F high and a 66°F low.
During the cooler months, from late November to mid-March, temperatures generally stay below 70°F, providing a comfortable contrast to the summer heat.
Winter is very mild in Pasadena, with December often being the coldest month, averaging around 56°F.
Rain is more frequent during this season, contributing to the area’s greenery and overall appeal. While snowfall is extremely rare, it did occur once back in 1949, making it a notable weather phenomenon for locals.
Pasadena’s climate is ideal for outdoor activities year-round, with ample sunshine even during the winter months.
The city benefits from longer daylight hours during the summer due to daylight saving time, which is perfect for enjoying its numerous parks and cultural attractions.
This climate information makes Pasadena an attractive destination for both residents and visitors seeking consistent and enjoyable weather conditions throughout the year.
For more details on Pasadena’s climate, you can explore the annual weather averages in Pasadena provided by various weather resources.
Average Temperature In Pasadena, California
Pasadena experiences mild and pleasant temperatures throughout the year. The average annual temperature is about 64°F.
Monthly Averages
January: The coldest month with an average temperature of 54.4°F. Highs reach around 68°F, and lows drop to 46°F.
February: Slightly warmer with average highs of 69°F and lows of 47°F.
March: Average temperatures rise to about 57°F, with highs around 72°F.
April: Springtime brings average highs of 76°F and lows near 50°F, making April weather quite pleasant.
May: Warming up to an average of 63°F, highs reach 79°F.
June: Average temperatures hover around 72°F, with highs of 84°F.
July: One of the warmest months, temperatures reach highs of 87°F and lows of 66°F.
August: The hottest month with average highs of 88°F and lows of 66°F. For more on temperature, check out this resource.
September: Temperatures start to cool slightly with highs around 84°F.
October: Average high temperatures drop to 77°F, and lows are around 58°F.
November: Cooling further with highs around 72°F and lows near 50°F.
December: Temperatures average 57°F, with highs of 68°F and lows of 47°F.
Average Precipitation In Pasadena, California
Pasadena, California, experiences varied precipitation throughout the year, with most rainfall occurring in the cooler months and snow being quite rare.
Average Rainfall In Pasadena, California
Pasadena gets most of its rain in the winter months. January and February are the wettest months, with about 4-5 inches of rain each. The total annual rainfall in Pasadena is around 20 inches.
Summertime is mostly dry, with very little rain.
In other months, the city receives smaller amounts of rain, typically a half-inch to an inch per month. For example, November and March each see about 2 inches.
This pattern of rainfall makes it important for residents to plan for wet winter conditions and dry summer weather.
Average Snow In Pasadena, California
Snow is uncommon in Pasadena. The elevation of the city and its proximity to the coast mean it rarely gets cold enough for snow. Typically, any precipitation in winter falls as rain.
On rare occasions, a light dusting of snow may occur, especially in the foothills or nearby mountains. These events are infrequent and usually do not have a significant impact on daily life in Pasadena.
If snow does occur, it is a rare and notable event that draws a lot of attention. More information about snow can be found in articles related to Snow and Ice.
Average Sun In Pasadena, California
Pasadena, California, enjoys a considerable amount of sunshine throughout the year, with varying levels of cloud coverage and daylight hours depending on the season.
Average Daily Shortwave Solar Energy In Pasadena, California
In Pasadena, the average daily shortwave solar energy varies with the time of year.
In the summer months, the city receives more solar energy due to longer daylight hours and clear skies. During this time, the average daily solar energy can peak at 6.7 kWh/m².
Winter brings shorter daylight hours and increased cloud coverage.
Despite this, Pasadena still receives a fair share of sunlight, averaging about 3.5 kWh/m² daily.
These variations in solar energy significantly influence the amount of daylight and sunshine the city experiences throughout the year.
Cloud coverage impacts sunlight hours, especially in the winter months. During these times, residents can expect fewer clear days and more overcast conditions, reducing the amount of direct solar energy.
For detailed month-by-month weather patterns, including sunlight hours and cloud coverage, visit Weather-Atlas Pasadena Climate.
Average Humidity in Pasadena, California
Pasadena, California experiences varying levels of humidity throughout the year.
Average Humidity by Month:
- May: The most humid month with an average of 73%.
- November: The least humid month with an average of 50%.
General Year-Round Humidity:
The average annual humidity in Pasadena is around 65%. This means residents can expect moderate humidity levels most of the time.
| Month | Average Humidity (%) |
|---|---|
| January | 67% |
| February | 66% |
| March | 65% |
| April | 65% |
| May | 73% |
| June | 68% |
| July | 67% |
| August | 67% |
| September | 65% |
| October | 60% |
| November | 50% |
| December | 59% |
Relative Humidity and Dew Point:
- Relative Humidity: Varies with the time of year, being highest in spring.
- Dew Point: Influenced by both temperature and humidity but generally lower during winter due to cooler temperatures.
For more specifics, including the detailed percentages, visit the Average humidity in Pasadena.
Average Wind In Pasadena, California
Wind conditions in Pasadena vary throughout the year. On average, wind speeds are generally calm to moderate.
Average Wind Speed:
- The wind speed tends to be around 5.7 mph (9.2 km/h) during most of the year.
The windiest month is typically May, with speeds averaging around 6.3 mph (10.1 km/h).
In contrast, December often experiences the calmest conditions, with wind speeds tapering to an average of 4.6 mph (7.4 km/h).
Monthly Wind Speed Data:
- January: 5.2 mph (8.4 km/h)
- February: 5.4 mph (8.7 km/h)
- March: 5.8 mph (9.3 km/h)
- April: 6.0 mph (9.7 km/h)
- May: 6.3 mph (10.1 km/h)
- June: 5.9 mph (9.5 km/h)
- July: 5.7 mph (9.2 km/h)
- August: 5.5 mph (8.9 km/h)
- September: 5.3 mph (8.5 km/h)
- October: 4.9 mph (7.9 km/h)
- November: 4.8 mph (7.7 km/h)
- December: 4.6 mph (7.4 km/h)
These varying wind speeds can impact outdoor activities and should be considered when planning events.
Average Air Quality In Pasadena, California
Pasadena generally has good air quality throughout the year. The city’s air quality index (AQI) is often classified as “Good,” meaning that air pollution poses little or no risk to health.
PM2.5 Levels:
- PM2.5, or fine particulate matter, is one of the primary pollutants.
- In Pasadena, PM2.5 levels are often well within safe limits.
Visibility in Pasadena can be affected by air pollution, though this is usually not a significant issue due to low levels of particulates.
Climate Impact on Air Quality:
- Summers are generally clear and hot, which helps disperse pollutants.
- Winters are cooler and partly cloudy, which can lead to occasional days with reduced air quality.
The air quality in Pasadena is relatively better compared to other neighborhoods in California, making it a healthier place for residents prone to respiratory conditions.
Weather Influence:
- Average temperatures range from 63.9°F yearly, peaking at 74.7°F in August.
- Seasonal changes cause fluctuations in pollutants but are usually mild.
Pressure and Humidity:
- Air pressure and humidity interact to influence pollutant concentration.
- Higher humidity in winter may lead to temporary drops in air quality.
Topography Of Pasadena, California
Pasadena is located in the San Gabriel Valley, nestled against the San Gabriel Mountains.
The city sits at an average elevation of about 864 feet above sea level, with some areas rising higher due to the mountainous terrain.
Mountain Ranges
- San Gabriel Mountains: These mountains form a natural northern boundary, providing scenic views and hiking opportunities.
- Angeles National Forest: Lies to the north, offering outdoor recreational areas and natural beauty.
Terrain
- Flat Areas: Central Pasadena has more flat terrain, which is ideal for urban development.
- Hilly Regions: Northern parts include hilly areas as the terrain rises towards the mountains.
- Arroyo Seco: A natural canyon that runs through Pasadena, featuring a mix of rugged terrain and green spaces.
Water Bodies
- Arroyo Seco Stream: This stream flows through Pasadena, contributing to the region’s natural landscape.
- Devil’s Gate Reservoir: Located to the northwest, it helps with flood control and provides recreational activities.
Parks and Green Spaces
- Brookside Park: One of the largest parks, located near the Rose Bowl.
- Eaton Canyon Natural Area: Offers trails, a nature center, and waterfall access.
Extreme Weather Events That Occur In Pasadena, California
Pasadena, California experiences a variety of extreme weather events. These events can pose risks to the community and impact daily life.
Heat Waves
Pasadena can experience intense heat waves, especially during summer months.
The temperature frequently exceeds 100°F. As climate change progresses, these heat waves are expected to become more frequent and severe, increasing the risk of heat-related illnesses.
Drought
Drought conditions are a significant concern in Pasadena. The region is prone to long periods without rainfall, which affects water supply and increases the risk of wildfires.
Drought risk in Pasadena is classified as extreme.
Wildfires
The combination of high temperatures and dry conditions makes Pasadena susceptible to wildfires.
These fires can spread rapidly due to dry vegetation and strong winds, causing damage to property and natural resources.
Heavy Rain and Flooding
Though less common, Pasadena can experience periods of heavy rain, particularly during the winter months.
These rains can lead to flooding in low-lying areas and cause mudslides on hillsides. Ensuring proper drainage and early warning systems can mitigate some of these risks.
Best Time Of The Year To Visit Pasadena, California
Pasadena offers different experiences in each season, making it a year-round destination.
The weather varies from warm summers to more moderate temperatures in fall and spring, with winter bringing cooler but pleasant conditions.
What Is Pasadena, California Like In Spring
Spring is one of the best times to visit Pasadena.
From April to May, the weather is mild and temperatures range from 60°F to 75°F. This season is known for its sunny days and minimal rainfall.
The city is in full bloom with colorful flowers, making it perfect for outdoor activities.
Popular events like the Pasadena Showcase House for the Arts take place, drawing visitors who enjoy culture and nature.
What Is Pasadena, California Like In Summer
Summer in Pasadena is hot, lasting from late June to September.
Temperatures often surpass 84°F, with August being the hottest month, averaging highs of 88°F and lows around 66°F.
The sunny and dry weather makes it ideal for poolside relaxation and water sports.
During this time, tourist activities like outdoor concerts and festivals are abundant.
Be prepared for the heat, and consider staying hydrated and sun-protected.
What Is Pasadena, California Like In Fall
Fall, especially from October to November, is another great time to visit.
Temperatures stay between 65°F and 80°F, offering comfortable weather for exploring the area. The season is generally mild and pleasant, although the Santa Ana winds can occur, bringing dry and warm conditions.
Fall is also the beginning of the event season, with several art fairs and food festivals.
The natural scenery changes as leaves turn, providing a beautiful backdrop for outdoor activities.
What Is Pasadena, California Like In Winter
Winter in Pasadena spans from late November to mid-March, with average high temperatures below 70°F.
January is the coolest month, with average highs around 63°F and lows near 45°F. Rainfall is more frequent but usually not heavy.
This season still offers plenty of sunshine, making it suitable for indoor cultural experiences and less crowded outdoor sites.
The mild winter makes Pasadena a cozy yet lively place to visit.