Climate and monthly weather forecast
South Dakota, USA

South Dakota has a temperate continental type of climate with warm and moderately humid summers and dry and cold winters. Nebraska to the south, Wyoming to the west, Montana to the northwest, North Dakota to the north, Minnesota to the east, and Iowa to the southeast share borders with the landlocked state. South Dakota, the Coyote state, is part of the American Midwest and lies in the Great Plains region, the land of many Indian reservations.

The Missouri River divides South Dakota into the distinct western and eastern parts called West River and East River. The Black Hills in the western part display a different climate subtype due to the unique geography - the mountains receive a high level of precipitation and have various species of pines such as the lodgepole and ponderosa. The majority of South Dakota is a temperate grassland prairie with hills, ravines, and flat-topped elevations occupying the rest - however, elms, willows, larches, and cottonwoods are common near the riverbeds. The western portion is semi-arid in places where the terrain is uneven and consists of badlands. The eastern part receives more rainfall than the western one and has few mountains of towering heights.

The best time to visit South Dakota is usually from late spring to autumn, particularly from May to October.
Summer is typically the peak tourist season, but late spring and autumn are generally better regarding accommodation and fewer crowds. June to August tends to have hot, dry, and humid days with the mercury often close to 90°F (32.2°C).
Late spring and early summer are prone to rain and thunderstorms, while autumn sees a reduction in storms and cooler temperatures than the summer. The fall season has pleasant weather with reduced humidity and rainfall.
Summers swell with tourists eager to visit Mount Rushmore and the state and national parks.

Winter is the worst time to visit South Dakota, with severe weather that often sees days and nights below freezing temperatures.
The majority of the state sees a substantial amount of snow, and mountains have deep snow packs. Wind Cave national park receives 41" (1041mm) of snow, while Mount Rushmore records 52" (1321mm) - it is a better idea to visit these places during the warm seasons than the biting cold of winter.
Local attractions draw some visitors to South Dakota during the winter, but the season registers significantly low tourist numbers compared to the summer.

Spring brings a moderate climate to South Dakota. Temperatures begin to climb, and the landscape starts to rejuvenate after the cold winter months. Daytime temperatures can range from 60°F (15.6°C) to 75°F (23.9°C), while nights remain cooler, settling between 40°F (4.4°C) to 55°F (12.8°C). This season also marks the beginning of the rainy period, with occasional thunderstorms, particularly in the southeastern region which is a part of Tornado Alley.

Summer in South Dakota is characterized by warm to hot conditions. Average high temperatures during July can vary from 80°F (26.7°C) to 90°F (32.2°C), with some days even surpassing 100°F (37.8°C), especially in the western semi-arid zones. The evenings offer a respite as temperatures drop to a comfortable range of 50°F (10°C) to 60°F (15.6°C). Alongside high temperatures, summer can bring occasional severe thunderstorms.

Autumn in South Dakota introduces cooler temperatures, making it a delightful season for tourists. With reduced humidity and rainfall, daytime temperatures usually remain between 60°F (15.6°C) and 75°F (23.9°C), while nighttime temperatures can fall to 40°F (4.4°C) to 55°F (12.8°C). The weather remains relatively stable, and the changing foliage offers a picturesque landscape, enhancing the state's beauty.

Winter sees South Dakota grappling with intense cold. January, in particular, experiences average high temperatures that stay below the freezing point. The lows can plummet to 10°F (-12.2°C) across most parts of the state. Snowfall becomes a common sight, with plains witnessing regular snow episodes. Mountainous regions can amass snowfall exceeding 100" (2540mm), showcasing a wintry landscape but imposing challenges for travel and outdoor activities.

January in South Dakota is characterized by its intense cold, typically registering as the coldest month of the entire year. Daytime temperatures often struggle to surpass the freezing point, with average highs below 32°F (0°C). Weather in January »

February in South Dakota witnesses a continuation of winter's icy grip, though there's a gradual transition towards slightly milder conditions as the month progresses. Daytime temperatures in February usually lie between 25°F (-3.9°C) and 35°F (1.7°C). Weather in February »

March ushers in the initial hints of spring for South Dakota, although winter's remnants are still palpable, especially in the early part of the month. Daytime temperatures in March experience a marked increase, generally fluctuating between 40°F (4.4°C) and 50°F (10°C). Weather in March »

April in South Dakota is a definitive shift into spring, with the landscape coming alive as temperatures rise and winter's grip loosens considerably. Daytime temperatures during this month generally settle between 55°F (12.8°C) and 65°F (18.3°C). Weather in April »

May in South Dakota sees a full embrace of spring, heralding the upcoming summer season with steadily rising temperatures and blooming landscapes. Daytime temperatures during this month comfortably oscillate between 65°F (18.3°C) and 75°F (23.9°C). Weather in May »

June in South Dakota signals the onset of summer, with the state experiencing warmer and drier conditions, along with longer daylight hours. Daytime temperatures predominantly hover between 75°F (23.9°C) and 85°F (29.4°C). The nights, in contrast, offer a pleasant respite from the daytime warmth, with lows generally settling between 55°F (12.8°C) and 65°F (18.3°C). The Black Hills, consistent with their unique climatic tendencies influenced by their geography, might occasionally see temperatures that are slightly cooler than the vast plains. Weather in June »

July stands as the zenith of the summer season in South Dakota, showcasing the warmest temperatures of the year. Daytime temperatures frequently scale the range from 80°F (26.7°C) to 90°F (32.2°C), with occasional surges beyond, especially in the semi-arid western belts. Weather in July »

August in South Dakota can be described as a transitional month, as the intense heat of peak summer begins to wane, making way for the early hints of the forthcoming autumn season. Daytime temperatures during August generally lie between 75°F (23.9°C) and 85°F (29.4°C). Weather in August »

September ushers in the full embrace of autumn in South Dakota, marked by cooler temperatures, transforming landscapes, and a shift in atmospheric conditions. Daytime temperatures predominantly range from 65°F (18.3°C) to 75°F (23.9°C), while the nights experience a more significant drop, settling between 45°F (7.2°C) and 55°F (12.8°C). Weather in September »

October in South Dakota is quintessentially autumnal, characterized by a refreshing crispness in the air, vibrant fall foliage, and the unmistakable anticipation of the approaching winter. Daytime temperatures during this month are notably cooler, ranging from 55°F (12.8°C) to 65°F (18.3°C). Weather in October »

As November rolls into South Dakota, the landscapes shift from the colorful tapestry of autumn to the stark and often snow-draped scenes of early winter. Daytime temperatures tend to hover between 40°F (4.4°C) and 50°F (10°C), while nighttime sees a sharper drop, often plummeting to between 20°F (-6.7°C) and 30°F (-1.1°C). Weather in November »

December in South Dakota is emblematic of winter in its full splendor. The state, blanketed in snow and gripped by the cold, exhibits a serene yet stark beauty. Daytime temperatures during December are typically quite chilly, fluctuating between 25°F (-3.9°C) and 35°F (1.7°C). Weather in December »