St. Louis Climate & Monthly Temperature Overview – United States

Seasons and Precipitation

St. Louis experiences four distinct seasons, with warm and humid summers and cold, snowy winters. Spring and fall are generally mild, but can be unpredictable with occasional fluctuations in temperature and precipitation. Summer months typically see high temperatures in the mid-80s Fahrenheit with high humidity, while winter temperatures average in the mid-30s Fahrenheit with frequent snowfalls. St. Louis receives an average of 39 inches of rainfall annually, with most precipitation occurring during the spring and summer months.

Temperature and Humidity

St. Louis’s climate is characterized by significant temperature variations throughout the year. Summers are hot and humid, with average high temperatures in the mid-80s Fahrenheit and average low temperatures in the mid-60s Fahrenheit. Winters are cold and snowy, with average high temperatures in the mid-30s Fahrenheit and average low temperatures in the mid-20s Fahrenheit. Humidity levels are generally high throughout the year, especially during the summer months, making the heat feel more oppressive. During the winter months, there can be extreme cold with occasional blizzards and wind chills below zero degrees Fahrenheit.

Average Temperatures Throughout the Year

St. Louis experiences a humid subtropical climate with distinct seasons. Summers are generally warm and humid, with average high temperatures ranging from 28°C (82°F) in September to 32°C (90°F) in July. The city also experiences occasional heat waves, with temperatures soaring above 38°C (100°F). Winters, on the other hand, are cold and damp, with average low temperatures dropping to -3°C (26°F) in January and February. St. Louis typically receives around 50 inches of rain per year, spread relatively evenly throughout the year.

Seasonal Variations in Temperature

Spring and fall in St. Louis offer pleasant weather with moderate temperatures. In April, the average high temperature reaches 18°C (64°F), while in October it drops to 16°C (61°F). During these seasons, the city experiences a mix of sunny and cloudy days, as well as occasional thunderstorms. Summer arrives in May, bringing with it warm and humid conditions. Temperatures gradually rise throughout the season, with July being the hottest month on average. Fall begins in September, bringing cooler temperatures and lower humidity levels. By November, the average high temperature drops to 11°C (52°F). Winter sets in during December, with cold and damp weather. Snowfall is common in January and February, but it typically melts quickly due to the city’s relatively mild climate.

Cloud Cover and Types

St. Louis, Missouri, experiences a wide range of cloud cover throughout the year, with the amount and type varying depending on the season. During the summer months, the city typically has a high percentage of cloud cover, often with cumulus or cumulonimbus clouds, which can bring thunderstorms. As fall approaches, the cloud cover gradually decreases, and stratus or cirrus clouds become more prevalent. Winter in St. Louis is characterized by a mix of cloud types, including stratocumulus, altocumulus, and cirrocumulus. During spring, the cloud cover typically increases again, with cumulus and altocumulus clouds being common.

Impact on Weather and Climate

Cloud cover has a significant impact on St. Louis’ weather and climate. On days with high cloud cover, temperatures tend to be cooler, as the clouds block out sunlight and reduce heating from the sun. Conversely, low cloud cover allows for more sunlight to reach the ground, leading to warmer temperatures. Additionally, cloud cover can affect precipitation patterns. Thick cloud layers can lead to heavy rainfall or snowfall, while thin cloud layers may cause only light precipitation or no precipitation at all. The presence of clouds can also influence wind patterns, as clouds can disrupt airflow and create wind gusts or updrafts.

Seasonal Patterns

St. Louis, Missouri, experiences a humid continental climate, with distinct seasonal variations in precipitation. During the spring and early summer (March to June), the city receives moderate rainfall, averaging around 3-4 inches per month. This precipitation is often associated with thunderstorms and frontal systems that bring moisture from the Gulf of Mexico.

In the summer (July to August), St. Louis typically experiences its wettest months, with an average of 5-6 inches of rain each month. This precipitation is often intense and can occur in the form of heavy thunderstorms. The summer months also coincide with the peak of the North American Monsoon, which can bring additional moisture to the region.

Annual Precipitation

On an annual basis, St. Louis receives an average of approximately 40-45 inches of precipitation. This places St. Louis in the middle range of precipitation for cities in the United States. However, it’s important to note that precipitation can vary significantly from year to year, influenced by factors such as El Niño-Southern Oscillation (ENSO) patterns and long-term climate trends.

Rainfall Variability in St. Louis

St. Louis experiences significant variability in rainfall patterns throughout the year. During the spring and summer months (March to August), convective thunderstorms are common, bringing heavy but sporadic rainfall. These thunderstorms often occur in the afternoons or evenings and can produce intense downpours and hail in localized areas.

In contrast, the fall and winter months (September to February) tend to witness less frequent yet more persistent rainfall, often associated with frontal systems or mid-latitude cyclones. These systems bring widespread, steady precipitation that can last for several days. As a result, fall and winter in St. Louis are typically characterized by lower precipitation totals but more consistent rainfall patterns compared to the spring and summer months.

Historical Snowfall Records

St. Louis, Missouri, has experienced significant snowfall throughout its history, with some notable events standing out. One of the most memorable is the Great Blizzard of 1918, which dumped an astonishing 20.3 inches of snow on the city. This event paralyzed transportation and left residents stranded, contributing to the outbreak of the Spanish Flu pandemic that followed. Another notable snowfall occurred on January 31st, 1964, when 16.6 inches of snow blanketed the city, leading to the cancellation of classes and disrupting travel.

Average Annual Snowfall and Winter Season

Over the years, St. Louis has averaged around 19 inches of snowfall annually, with significant variations from year to year. The winter season typically lasts from December to February, with the heaviest snowfall occurring in January. However, snowfall can occur as early as October and as late as April, making it essential for residents to be prepared for winter weather conditions.

Average Monthly Sunlight

St. Louis experiences significant seasonal variations in sunlight duration. During the summer months (June to August), the city enjoys ample sunshine, with an average of 10-12 hours of bright sunlight per day. The longest day of the year occurs around June 21st, offering nearly 14 hours of daylight. In contrast, winter days are much shorter, averaging only 4-6 hours of sunlight per day. The shortest day of the year is December 21st, with only around 9 hours of daylight.

Seasonal Sunlight Patterns

The transition from summer to winter and vice versa brings about noticeable changes in sunlight patterns. As the days shorten in autumn, the amount of sunlight gradually diminishes. This trend continues throughout December, resulting in the shortest days of the year. However, as spring approaches, sunlight duration begins to increase again. By April, the city starts to experience longer days and warmer temperatures. The increase in sunlight stimulates plant growth and invigorates the local ecosystem.

Moonrise in St. Louis

The moonrise in St. Louis, United States, is a breathtaking sight that can be enjoyed on clear nights. As the sun sets, the sky transforms into a canvas of vibrant hues, casting a warm glow over the cityscape. Slowly, the moon begins to peek over the horizon, its silvery orb gradually illuminating the surroundings. The contrast between the fading daylight and the emerging moonlight creates a surreal and enchanting atmosphere.

Moonset in St. Louis

The moonset in St. Louis is equally captivating, offering a different perspective on the city’s skyline. As the night reaches its peak, the moon begins to descend towards the horizon. Its waning glow casts an ethereal light upon the buildings and landmarks, transforming them into silhouettes against the darkening sky. As the moon dips below the horizon, it leaves behind a lingering glow that gradually fades into darkness, signaling the end of another celestial cycle.

Seasonal Humidity

St. Louis, Missouri, experiences distinct seasonal variations in humidity. Winters are generally dry, with relative humidity levels averaging around 60-70%. The humidity gradually increases during spring and peaks in the summer months, particularly in July and August. During these peak summer months, relative humidity levels can soar to 80-90%, creating a hot and muggy environment. Fall brings a gradual decline in humidity, returning to the relatively dry conditions of winter.

Factors Influencing Humidity

Several factors contribute to the seasonal fluctuations in humidity in St. Louis. The city’s location near the Mississippi River and its humid subtropical climate create a humid environment. During the summer months, warm, moist air from the Gulf of Mexico moves northward, resulting in high humidity. In contrast, during winter, cold and dry air from the north dominates, reducing humidity levels. Additionally, St. Louis often experiences thunderstorms during the summer, which can temporarily increase humidity levels as they release moisture into the atmosphere.

Wind Patterns in St. Louis

St. Louis, Missouri, is located in the central United States and experiences a humid continental climate with distinct seasons. The city is known for its variable winds, with the prevailing wind direction being from the southwest. This wind pattern is influenced by the region’s location within the Mississippi River Valley and the presence of the Ozark Mountains to the west. The prevailing southwest winds transport warm, moist air from the Gulf of Mexico into the Midwest, contributing to the humid conditions in St. Louis. Additionally, the city’s proximity to the Mississippi River can result in strong northerly winds during cold fronts, which can bring colder and drier air masses from the north.

Seasonal Variations in Wind Speed and Direction

The wind patterns in St. Louis exhibit seasonal variations. During the spring and fall, the prevailing winds tend to be from the southwest, with moderate wind speeds. However, during the summer, the winds become more variable in direction and speed. This is due to the frequent passage of cold fronts and thunderstorms, which can cause sudden shifts in wind direction and intensity. In the winter, the prevailing winds typically become stronger and more frequent from the north, bringing colder and drier air masses into the region. Additionally, St. Louis is occasionally affected by strong winds associated with low-pressure systems, such as nor’easters and cyclones, which can bring high winds and precipitation to the area.

Spring (March-May):

Spring in St. Louis is a vibrant time, with temperatures gradually warming and ample sunshine. The city comes alive with blooming flowers and lush greenery. It’s an excellent time for outdoor activities like exploring Forest Park, visiting the Missouri Botanical Garden, or enjoying a picnic along the Mississippi Riverfront. Festivals such as the Saint Louis Earth Day Festival and the Saint Louis Food and Drink Festival add to the lively atmosphere.

Fall (September-November):

Fall is another ideal season for visiting St. Louis. The heat of summer has subsided, replaced by crisp autumn air and vibrant foliage. It’s the perfect time for walking tours of the historic neighborhoods, such as Soulard and Lafayette Square. Attend festivals like the St. Louis Blues Heritage Festival or the Great Forest Park Balloon Race, offering unique and memorable experiences. Fall is also a popular time for sports enthusiasts, as the St. Louis Cardinals baseball team is in full swing at Busch Stadium.

Solar Energy Potential and Incentives

St. Louis, Missouri has a promising solar energy potential, with an average of 4 peak sunlight hours per day. The city offers various incentives to encourage solar adoption, such as the Missouri Solar Investment Tax Credit (ITC), which provides a 30% tax credit for installing solar systems. Additionally, St. Louis’s Green Fund offers grants and rebates for renewable energy projects.

Solar Installation and Costs

The cost of installing a solar system in St. Louis varies depending on factors such as system size, equipment selection, and labor costs. On average, a residential solar system with a capacity of 5 kilowatts (kW) can cost around $15,000 to $20,000 before incentives. Solar panel installation companies in St. Louis include SunPower, Sunrun, and Vivint Solar. With the availability of tax credits and incentives, the payback period for a solar system in St. Louis typically ranges from 8 to 12 years.

Mississippi River Valley

St. Louis is situated at the confluence of the Mississippi and Missouri Rivers. The Mississippi River Valley, which encompasses the city, is characterized by a relatively flat landscape with gently rolling hills. The valley floor is composed of alluvial sediments deposited by the rivers over millions of years. The bluffs that line the Mississippi River rise abruptly from the valley floor, reaching heights of up to 200 feet. The bluffs are a prominent feature of the St. Louis skyline and offer panoramic views of the city and the river.

Dissected Uplands

To the west of St. Louis, the landscape transitions into dissected uplands. This region is characterized by a series of hills and valleys that were carved out by streams and rivers. The hills are typically capped with a layer of limestone, which has been eroded over time to form caves and sinkholes. The valleys are filled with a mix of loess, a windblown sediment, and glacial till, a deposit of rocks and sediments left behind by glaciers. The dissected uplands provide a rugged and diverse topography, with woodland areas, steep slopes, and natural springs.

Lambert-St. Louis International Airport (STL)

Lambert-St. Louis International Airport (STL) is the primary airport serving the St. Louis metropolitan area. It is located approximately 12 miles northwest of downtown St. Louis in the city of Berkeley, Missouri. STL is the busiest airport in Missouri and ranks among the top 50 airports in the United States by passenger traffic. The airport is a hub for Southwest Airlines and offers direct flights to over 100 destinations worldwide. STL features modern facilities, including four runways, three terminals, and a large retail and dining area. The airport is easily accessible via major highways and public transportation.

Other Nearby Airports

While STL is the closest airport to St. Louis, there are several other airports within a reasonable driving distance. These include:

• MidAmerica St. Louis Airport (BLV) is a general aviation airport located approximately 25 miles northeast of downtown St. Louis. It is primarily used for private and corporate aircraft.
• Spirit of St. Louis Airport (SUS) is a general aviation airport located approximately 15 miles west of downtown St. Louis. It is used for both private and commercial flights, including charter flights and flight training.
• St. Louis Downtown Airport (CPS) is a general aviation airport located just south of downtown St. Louis. It is primarily used for private and corporate aircraft.

History of St. Louis

St. Louis, a vibrant city in the heart of the United States, boasts a rich and captivating history. Founded by French fur traders in the early 18th century, the city served as a gateway to the vast American interior. During the westward expansion, St. Louis became a major hub for exploration and trade, earning the nickname “The Gateway to the West.” Its strategic location at the confluence of the Mississippi and Missouri rivers facilitated the movement of settlers, goods, and ideas. As the city grew, it played a pivotal role in the American Civil War and the Civil Rights Movement, leaving a lasting legacy of social and cultural change.

Culture and Attractions

St. Louis is renowned for its vibrant culture, diverse neighborhoods, and world-class attractions. The city is home to iconic landmarks such as the Gateway Arch, a soaring symbol of American ingenuity and westward expansion. Visitors can explore the bustling downtown area, known for its historic buildings, museums, and theaters. Forest Park, one of the largest urban parks in the country, offers a serene escape with lush gardens, museums, and the iconic Saint Louis Zoo. The city’s vibrant arts scene is showcased through renowned museums such as the Saint Louis Art Museum and the Contemporary Art Museum St. Louis. St. Louis is also known for its unique cuisine, featuring traditional dishes such as toasted ravioli and gooey butter cake. The city’s passion for sports is evident in the enthusiastic support for the St. Louis Cardinals baseball team and the St. Louis Blues hockey team.