Sunnyvale, California – Climate and Average Weather Year Round: A Comprehensive Guide

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Nestled in the heart of California’s Silicon Valley, Sunnyvale boasts a climate that lives up to its name.

This vibrant city experiences mild, pleasant weather throughout the year, making it a desirable location for residents and visitors alike.

The hottest month in Sunnyvale is August, with average highs reaching 76°F and lows around 60°F. This consistent warmth, paired with the city’s robust tech industry, makes Sunnyvale a hotspot for innovation and relaxation.

During the cooler months, Sunnyvale still manages to offer comfortable weather.

From late November to early February, temperatures drop, with the coldest month being December.

In December, highs average 59°F while lows can dip to 45°F. Despite the cooler temperatures, the city remains an attractive option for those looking to escape harsher winters found elsewhere in the Northern Hemisphere.

Sunnyvale’s climate is well-documented through various weather reports and data collected over the years.

This information is crucial for anyone planning to move to or visit the city.

Weather apps and climate graphs provide detailed insights into Sunnyvale’s yearly weather conditions, ensuring that people can prepare for any season.

For those interested in the specifics, more detailed average weather data for Sunnyvale can be found online.

Average Temperature in Sunnyvale, California

Sunnyvale, California, enjoys mild and pleasant temperatures throughout the year. The climate here is characterized by warm, dry summers and mild, wet winters.

Summer temperatures are usually warm.

The hottest month is often September, with average high temperatures reaching around 68.2°F. The daily temperature generally stays between 77°F and 87°F.

Winter brings cooler weather to Sunnyvale.

January is typically the coldest month, with average low temperatures around 49.9°F. It’s rare for the temperature to drop below 36°F.

Month High Temp (°F) Low Temp (°F)
January 59 44
September 77 56

The annual weather averages show a consistent pattern.

Throughout the year, temperatures usually stay within a comfortable range, making Sunnyvale an ideal place for those who prefer mild climates.

During the summer months, you can expect long days with plenty of sunshine, while the winters are shorter, colder, and wetter. Winter temperatures rarely exceed 60°F.

The average low temperature remains fairly mild throughout the year.

Even during the colder months, the temperature doesn’t drop significantly.

The weather averages highlight a balanced climate suitable for outdoor activities year-round.

Sunnyvale’s climate can be ideal for those looking for moderate weather without severe extremes. The annual temperature data highlights the city’s average temperature stability and comfort.

Average Precipitation in Sunnyvale, California

Sunnyvale, California experiences a Mediterranean climate with wet winters and dry summers. Precipitation levels fluctuate significantly throughout the year.

Average Rainfall in Sunnyvale, California

Rainfall in Sunnyvale is concentrated during the cooler winter months.

The wettest month is typically January, with an average of 3.7 inches of rainfall. The annual precipitation is around 15 inches.

Rainy days are common from November to March, with December and January having the most.

During these months, daily rainfall can often exceed half an inch.

From April to October, rainfall is sparse.

June, July, and August are usually the driest, with almost no rain recorded.

This seasonal variation results from the region’s Mediterranean climate, which features wet winters and dry summers.

Overall, a clear pattern of high rainfall during the winter and dry spells in the summer characterizes Sunnyvale’s weather.

Average Snow in Sunnyvale, California

Snow is a rare occurrence in Sunnyvale. The city’s average annual snowfall is virtually zero due to its mild winter temperatures.

The last significant snow event in the region dates back several decades.

Instead of snow, the area experiences rainfall during the colder months.

The absence of snow and ice means residents do not need to prepare for winter conditions often seen in other parts of the country. This makes Sunnyvale an attractive place for those who prefer milder winters without the hassle of snow removal.

Average Sun in Sunnyvale, California

Sunnyvale enjoys a healthy amount of sunshine year-round. The daily shortwave solar energy and hours of sunshine vary with the seasons, giving residents plenty of sun.

Average Daily Shortwave Solar Energy in Sunnyvale, California

Sunnyvale benefits from a significant amount of daily shortwave solar energy throughout the year.

During the summer months, residents can expect long sunshine hours, sometimes reaching up to 14.7 hours of daylight per day. The high UV index during these times means that sun protection is important.

In contrast, the winter months bring shorter days with reduced sunshine, often down to 10 hours per day.

The shortest day typically happens in late December, while the longest day occurs around late June. This fluctuation in sunlight impacts various activities and lifestyles in Sunnyvale.

Average Humidity in Sunnyvale, California

Sunnyvale, California, experiences various humidity levels throughout the year.

The average annual relative humidity is about 75%. This indicates the amount of moisture in the air compared to the maximum amount the air can hold at a given temperature.

The most humid month in Sunnyvale is January, with an average relative humidity of 80%. During this month, mornings can feel particularly damp, making the cold feel even colder.

In contrast, October is the least humid month, with an average relative humidity of 71%. During this time, the weather feels drier, and the air lacks the moisture common during other months.

The dew point, which is the temperature at which air becomes saturated and forms dew, also fluctuates throughout the year.

Higher dew points are often observed during the summer months, contributing to a feeling of mugginess.

Here’s a summary of monthly average relative humidity:

Month Relative Humidity (%)
January 80
February 78
March 76
April 74
May 72
June 71
July 71
August 72
September 70
October 71
November 74
December 77

For those living in or visiting Sunnyvale, understanding these humidity patterns can help in planning activities and daily routines.

Average Wind in Sunnyvale, California

Sunnyvale experiences moderate wind conditions throughout the year.

The average wind speed tends to range between 5 to 10 mph. The wind speed can occasionally reach higher speeds during certain months.

Windiest Month:
March is the windiest month. During this period, residents often notice stronger breezes with speeds averaging around 10 mph.

Wind Direction:
Winds primarily come from the west. This western wind pattern is consistent throughout most of the year.

In summary, the wind conditions in Sunnyvale are fairly stable and predictable.

This information is useful for planning outdoor activities and events. For more detailed articles on wind patterns, visit wind patterns.

Average Air Quality in Sunnyvale, California

Sunnyvale, California typically enjoys good air quality for most of the year.

According to the IQAir Air Quality Index (AQI), Sunnyvale often has AQI ratings in the “Good” range. This means that the air is generally safe for the entire population.

During certain times, air pollution can be higher due to factors like wildfires or seasonal changes.

People with respiratory issues should particularly monitor the AQI during these periods.

Listed below are common pollutants tracked in Sunnyvale:

  • Particulate Matter (PM2.5, PM10)
  • Ozone (O3)
  • Nitrogen Dioxide (NO2)

Localized air quality data can be helpful for making daily decisions.

For up-to-date information, residents can use resources like AccuWeather or Plume Labs.

Real-time tracking allows residents to plan outdoor activities when air quality is at its best.

Sunnyvale’s average weather conditions can also influence air quality.

During the summer, warm and mostly clear skies often lead to better air visibility.

Conversely, colder and partly cloudy winters, with an average of 44°F, can sometimes trap pollutants near the ground, reducing air quality temporarily.

Pressure and visibility metrics also play a role.

Higher atmospheric pressure generally means clearer skies and better air quality.

Visibility, closely tied to pollution levels, is typically high but can drop during pollution spikes.

Topography of Sunnyvale, California

Sunnyvale is located in Santa Clara County with elevations ranging from 79 feet to 492 feet above sea level.

The average elevation of the city is around 79 feet. The city’s terrain is relatively flat, which makes it ideal for biking and walking.

The lowest elevation is found in the northern parts of the city and can be as low as -49 feet. In contrast, the highest point is at 492 feet.

This range provides a slight variation in landscape, but Sunnyvale remains predominantly flat.

The city covers a total area of 22.7 square miles. Of this, 22.0 square miles is land, and 0.69 square miles is water.

This means that approximately 3.09% of Sunnyvale is composed of water bodies.

The topography influences the climate, with the flat terrain allowing for moderate winds and contributing to the mild Mediterranean climate Sunnyvale experiences.

The terrain also plays a role in drainage and development planning, ensuring that the city remains navigable and pleasant for its residents year-round.

Extreme Weather Events that Occur in Sunnyvale, California

Sunnyvale experiences various extreme weather events throughout the year. These events can impact daily life and safety.

Heatwaves

Heatwaves are common, especially in the summer when temperatures can soar.

On extremely hot days, temperatures can exceed 100°F. This can cause heat-related illnesses and pose risks, especially for the elderly and young children.

Wildfires

Sunnyvale, like other parts of California, is prone to wildfires.

The dry, hot climate, coupled with strong winds, can spark and spread fires quickly. Wildfires in nearby regions can also affect Sunnyvale’s air quality.

Heavy Rainfall and Flooding

Rainfall in Sunnyvale is generally low, but heavy rain events can lead to flooding.

This usually happens during the winter months. Flooding can disrupt transportation and damage property.

Month Average Rainfall
January 2.91 inches
February 2.59 inches
March 2.00 inches

Earthquakes

Although not a weather event, earthquakes are a significant natural hazard in the area.

Sunnyvale is located near several fault lines, making it susceptible to tremors.

Air Quality Alerts

Due to its proximity to wildfire-prone areas, Sunnyvale often faces air quality alerts.

Smoke and particulate matter from fires can cause respiratory issues and other health problems.

To stay safe during these events, it’s crucial for residents to stay informed and prepared.

Best Time of the Year to Visit Sunnyvale, California

Sunnyvale offers a mix of mild winters and warm summers, with spring and fall providing some of the most pleasant conditions.

Summer features long daylight hours, making it great for outdoor activities.

What is Sunnyvale, California Like in Spring

Spring in Sunnyvale, from March to May, is marked by mild temperatures and increasing sunshine.

Average highs range from 63°F in March to 74°F in May.

Rainfall is more common in March, tapering off by May.

Visitors can expect around 14 hours of daylight by the end of the season.

This makes spring a great time for outdoor activities and exploring local parks without the intense heat of summer. Blossoming trees and flowers add natural beauty to the cityscape.

What is Sunnyvale, California Like in Summer

Summer in Sunnyvale lasts from June to August, with average daily high temperatures above 73°F.

The hottest month is August, with highs averaging around 76°F and lows around 60°F.

Sunnyvale experiences long days with up to 14.7 hours of sunshine.

Rainfall is minimal, making it the perfect season for beach trips, hiking, and other outdoor pursuits.

The dry weather keeps the humidity low, providing comfortable conditions for visitors and residents alike.

What is Sunnyvale, California Like in Fall

Fall in Sunnyvale, from September to November, sees slightly cooler temperatures than summer.

September remains warm with highs around 68°F, gradually dropping to around 60°F by November.

The weather remains dry, offering clear skies and pleasant conditions.

This season provides an excellent opportunity for exploring the region’s vineyards and enjoying outdoor festivals.

Daylight hours begin to shorten, but there is still plenty of sunshine to enjoy.

What is Sunnyvale, California Like in Winter

Winter in Sunnyvale lasts from December to February and is noted for its mild, wet conditions.

Temperatures range from an average high of 60°F in December and January to a low of 40°F.

Rain is more frequent during these months, making it the wettest season.

Despite the increased precipitation, Sunnyvale rarely experiences extreme cold.

Visitors can still enjoy outdoor activities with appropriate rain gear, while indoor attractions and events offer alternative activities.

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