Boise, Idaho – Climate and Average Weather Year Round: An In-Depth Overview

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In Boise, Idaho, the climate offers a diverse range of weather conditions throughout the year.

The summers are short, hot, dry, and mostly clear, while winters are very cold, snowy, and partly cloudy.

Temperatures typically range from 24°F to 93°F, rarely dipping below 10°F or climbing above 101°F. This makes Boise a place for both summer and winter enthusiasts to enjoy various outdoor activities.

Located in Ada County, Boise is the largest city in Idaho and serves as the state capital.

The semi-arid climate results in an average annual precipitation of just over 11 inches, with the majority falling in the cooler months.

The Boise Air Terminal records the city’s weather data, giving a comprehensive look at the local climate trends.

Residents and visitors can expect nearly 15 to 15.4 hours of daylight in June and July, making it perfect for long summer days filled with activities.

Winter, on the other hand, brings shorter days and significant snowfall, creating a picturesque backdrop for winter sports.

This combination of summer warmth and winter chill makes Boise an interesting place to experience the changing seasons in the northern hemisphere.

Average Temperature In Boise, Idaho

Boise, Idaho experiences a wide range of temperatures throughout the year.

In the hot season, which lasts for almost three months from mid-June to early September, average daily high temperatures are above 82ºF.

July, the warmest month, has an average high of 92°F and a low of 62°F.

During the cold season, spanning from mid-November to late February, average daily high temperatures drop below 46ºF.

December is typically the coldest month with an average high of 37°F and a low of 25°F.

A typical year in Boise also sees an average high temperature of around 93ºF and a low of about 25ºF.

The mean temperature for the year is around 53°F, striking a balance between warm and cold times of the year.

Boise experiences highs of up to 111ºF, recorded on July 19, 1960, and the lowest temperature ever recorded was 25 degrees below zero on December 22, 1990.

Average Precipitation In Boise, Idaho

Boise experiences a semi-arid climate with distinct patterns of rainfall and snowfall. The area’s precipitation is relatively low compared to other regions.

Average Rainfall In Boise, Idaho

Boise receives an average annual rainfall of just over 11 inches. Most of the rain falls between November and May, with December being the wettest month.

The city experiences very dry summers, with minimal rain in July and August.

Rainfall is usually light, and heavy rainstorms are rare. The area’s low precipitation is a defining feature of its semi-arid climate.

For those interested in snowfall, more details can be found in the next subsection.

Average Snow In Boise, Idaho

Snowfall in Boise is also limited, averaging around 18 inches per year.

The heaviest snow typically falls in December and January. By late February, snowfall amounts begin to decrease as temperatures rise.

Snow and ice events are infrequent, making winter travel generally manageable.

The city’s snowfall contributes to its overall precipitation totals but remains modest compared to regions with harsher winters.

Average Sun In Boise, Idaho

Boise, Idaho experiences varied amounts of sunshine throughout the year, affecting both daily life and outdoor activities. The city’s climate features significant differences in daylight hours between summer and winter.

Average Daily Shortwave Solar Energy In Boise, Idaho

In Boise, the amount of daily shortwave solar energy changes throughout the year.

During the summer months, Boise sees its peak sunlight. June and July are particularly sunny, offering as much as 15 to 15.4 hours of daylight.

This means longer days filled with more sunshine, which is perfect for outdoor activities.

In contrast, winter days are much shorter with significantly less daylight. December has the least amount of sunshine hours, with days barely reaching 9 hours from sunrise to sunset.

This reduction in daylight impacts daily routines and energy consumption. Boise’s shortwave solar energy is lowest in these winter months.

These variations in solar energy and daylight hours are important for planning outdoor activities and for understanding how much natural light Boise residents can expect throughout the year.

Average Humidity In Boise, Idaho

Boise, Idaho experiences varying humidity levels throughout the year.

January is the most humid month, with an average relative humidity of 75%.

In contrast, July has the least humidity, averaging around 36%.

This significant difference makes Boise feel much drier in summer months compared to winter.

The average annual humidity in Boise is 55%. This places it in a comfortable range for many people most of the year.

Dew points also vary, reflecting the changes in moisture. For instance, the annual average dew point is about 33°F.

Month Humidity (%)
January 75
July 36
Annual 55

Understanding these patterns helps in planning activities and managing comfort in different seasons.

For more detailed information on Boise’s climate, visit World Weather & Climate Information and Time and Date.

Average Wind In Boise, Idaho

Wind conditions in Boise, Idaho, show distinct patterns throughout the year.

Average wind speeds are generally moderate, with most months experiencing peaks around 10 miles per hour (mph).

During the spring and fall, wind speeds can rise slightly due to weather changes and increased surface movement.

Monthly Average Wind Speeds:

  • January: 8 mph
  • February: 9 mph
  • March: 10 mph
  • April: 11 mph

The windiest month in Boise is typically April, with average speeds reaching up to 11 mph.

This period sees more dynamic surface movement, influenced by the changing seasons.

Boise experiences its calmest conditions during the summer months, particularly in July and August, where average speeds drop to around 7 mph. This provides a favorable environment for outdoor activities.

Throughout the year, the prevailing wind direction is from the northwest, though this can vary slightly during different seasons. The combination of elevation and geographical location contributes to these wind patterns.

Wind conditions are a crucial factor for residents and visitors alike, especially those engaging in activities like hiking or cycling. Understanding these patterns can help in planning activities and staying safe during periods of higher winds.

Average Air Quality In Boise, Idaho

The air quality in Boise, Idaho, can vary significantly throughout the year.

PM2.5 Levels:

  • PM2.5, tiny particulate matter, is the most significant factor impacting Boise’s air.

High levels are common in summer due to wildfires in Idaho and neighboring states. These particles can adversely affect health, especially for sensitive groups.

Air Quality Index (AQI):

  • The Boise AQI often ranges from “Good” to “Unhealthy for Sensitive Groups.”

During wildfires, it can reach even higher levels, indicating poor air quality.

Seasonal Variations:

  • Summer: Wildfires can increase PM2.5 levels, resulting in poorer air quality.
  • Winter: Inversions can trap pollutants close to the ground, negatively affecting air quality.

Weather Impact:

  • Cloud Cover: This can affect temperatures and air quality. More cloud cover can lead to higher pollutant levels as they trap air close to the surface.
  • Pressure: Barometric pressure affects air movement. High pressure can result in stagnation, reducing air dispersion.
  • Visibility: Reduced visibility often indicates higher pollution levels. This can be particularly noticeable during wildfire events.

Real-Time Monitoring:

Boise residents often rely on real-time data to make daily decisions on outdoor activities due to these frequent changes in air quality.

Topography Of Boise, Idaho

Boise, Idaho is located in Ada County at the coordinates 43.6150° N latitude and 116.2023° W longitude. The city is nestled in the Treasure Valley on the western edge of the state.

The average elevation of Boise is approximately 3,412 feet. The terrain around Boise varies widely. The minimum elevation in the region is about 2,500 feet, while the maximum elevation reaches up to 7,556 feet.

The area is characterized by its mountainous landscape. The Rocky Mountains to the north and east create a dramatic backdrop.

Boise’s altitude influences its semi-arid climate, which produces low rainfall and significant temperature variations.

The Boise River runs through the heart of the city, providing a scenic waterway that contributes to the area’s geography.

The foothills near Boise offer a range of elevations and terrains, popular for hiking and outdoor activities.

These topographical features play a significant role in shaping the local climate, landscape, and recreational opportunities in Boise.

Almost any exploration of Boise will reveal its varied elevation and striking landscapes, from urban flatlands to rugged mountain peaks, making it an interesting city to study and visit.

The combination of river valleys and mountain ranges gives Boise a unique topographical identity.

Extreme Weather Events That Occur In Boise, Idaho

Boise faces a variety of extreme weather events throughout the year.

These include thunderstorms, heatwaves, and cold snaps.

In recent years, the city has experienced more frequent and intense thunderstorms.

One notable storm occurred in June 2024, causing significant damage to properties and power lines.

Supercell thunderstorms have also led to wildfires in the region.

Heatwaves are becoming more common, pushing temperatures well above the average.

The hottest month is typically July, with temperatures often exceeding 90°F.

Extreme temperatures can cause unique hazards, such as falling tree limbs from stressed trees.

Boise also deals with freezing temperatures during winter.

The coldest month is usually January, with temperatures occasionally dropping below 20°F.

These cold snaps can cause difficulties for residents, especially in areas not equipped to handle prolonged freezing conditions.

The wettest month in Boise tends to be December, though overall precipitation is low compared to other regions.

In the past, the city averaged around 13.1 inches of rain per year, but this has decreased to about 11.6 inches.

Climate change effects have likely contributed to these changing weather patterns.

Best Time Of The Year To Visit Boise, Idaho

Boise, Idaho offers diverse experiences throughout the year, making it suitable for different preferences.

From mild springs to snowy winters, each season has unique attractions.

What Is Boise, Idaho Like In Spring

Spring in Boise, spanning March to May, brings mild temperatures ideal for outdoor activities.

March temperatures average between 34°F and 56°F, while May warms up to 45°F to 70°F.

This season sees moderate rainfall around 1.5 inches per month, which helps to keep the landscape green and vibrant.

  • Activities: Spring is perfect for hiking, biking, and exploring the Boise River Greenbelt.
  • The blooming flowers in local parks and gardens provide beautiful scenery for outdoor enthusiasts.
  • Events: Popular events include the Gene Harris Jazz Festival and the Boise Farmers Market, which opens in April.

What Is Boise, Idaho Like In Summer

Summer in Boise, from June to August, experiences hot and dry conditions.

July is the hottest month, with temperatures ranging from 62°F to 92°F. Precipitation is minimal, often less than 0.5 inches per month.

  • Activities: Summer is perfect for river rafting, paddleboarding on the Boise River, and attending outdoor concerts.
  • The long daylight hours, nearly 15.4 hours in June, provide ample time for exploration.
  • Events: The annual Boise Music Festival in June and Art in the Park in September are major attractions.

What Is Boise, Idaho Like In Fall

Fall in Boise, from September to November, features cooler temperatures and beautiful autumn foliage.

September starts with highs around 77°F, dropping to 44°F in November. Rainfall increases slightly, averaging around 1 inch per month.

  • Activities: This season is ideal for hiking in the nearby foothills, visiting local vineyards, and enjoying scenic drives.
  • The crisp air makes it a comfortable time for outdoor activities.
  • Events: Visitors can enjoy the Hyde Park Street Fair in September and Boise State football games.

What Is Boise, Idaho Like In Winter

Winter in Boise, lasting from December to February, brings cold temperatures and occasional snowfall.

January is the coldest month, with average highs of 37°F and lows around 24°F.

Snowfall is moderate, with snowstorms delivering 2-4 inches on average.

  • Activities:
  • Winter sports like skiing and snowboarding are popular, especially at nearby Bogus Basin.
  • Ice skating and holiday festivals also draw visitors.
  • Events:
  • The Winter Garden aGlow at the Idaho Botanical Garden in December and the McCall Winter Carnival in January are highlights.
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