Last updated: February 24, 2025
May in Rapid City, United States, showcases a fascinating range of temperatures, with maximums reaching 30°C (86°F) and minimums dipping to -4°C (24°F). The average temperature settles around a comfortable 11°C (53°F), providing a variable but pleasant climate. This month observes considerable precipitation, totaling 112 mm (4.4 in) over 17 days, contributing to a humidity level of 74%. As spring unfolds, the combination of warmth and moisture gives the landscape a vibrant character, making Rapid City an intriguing destination during this transitional season.
In May, Rapid City transitions into a more temperate climate, showcasing a significant improvement from the harsh winter months. With a minimum temperature of -4°C (24°F) and an average reaching 11°C (53°F), the city begins to enjoy the initial warmth of spring. The maximum daytime temperature can soar to 30°C (86°F), inviting outdoor activities and a vibrant atmosphere. This month marks a turning point, as temperatures steadily rise from the chill of April’s lows while hinting at the impending heat of June and July. Overall, May serves as a delightful bridge between winter's cold embrace and summer's warmth, encouraging both residents and visitors to embrace the blossoming beauty of Rapid City.
May in Rapid City marks a significant uptick in precipitation, with 112 mm (4.4 in) of rainfall over 17 days, making it one of the wettest months of the year. This is a sharp increase compared to the preceding months, following April's 73 mm (2.9 in) and showcasing nature’s vibrant transition into spring. As the city shakes off the lingering chill of winter, the frequency of rainy days also spikes, reflecting a shift toward a more temperate climate, ideal for blossoming flora. This pattern suggests that May serves as a crucial watering period, setting the stage for lush landscapes throughout the summer months.
In May, Rapid City experiences a comfortable humidity level of 74%, striking a balance between the drier conditions of earlier spring months and the higher humidity that follows in summer. This slight increase from April's 66% indicates a gradual transition towards the more humid months of June and July, which average around 84% and 85%, respectively. This trend highlights a shift from the cool, crisp air of the early year, where humidity levels tend to hover between 64% and 78%, to the more oppressive, moisture-laden environment of mid-summer. Overall, May's humidity serves as a gentle prelude to the more humid weeks ahead, inviting residents and visitors alike to enjoy the mild weather before the summer heat sets in.
In May, Rapid City experiences a very high UV Index of 9, similar to the preceding month of April, indicating a consistent trend of increased sun intensity as spring transitions into summer. With a burn time of just 15 minutes, it's crucial for residents and visitors to take protective measures against sun exposure. The UV Index in May mirrors the data seen in April, emphasizing the need for vigilance during outdoor activities. As the months progress into June and July, the UV Index escalates to an extreme level of 11, further highlighting the importance of sun safety this time of year. To learn more about the UV Index throughout the year, visit Rapid City UV Index.
UV Risk Categories
May graces Rapid City with a splendid 300 hours of sunshine, marking a delightful peak in the spring season. As the days grow longer and warmer, sunshine hours increase steadily from 169 hours in January to a vibrant 376 hours in June. This upward trend reflects the city’s transformation, with May serving as a gateway to summer. The consistent rise in sunlight not only enhances the picturesque landscapes but also invites residents and visitors to enjoy the multitude of outdoor activities that the region offers. As spring breathes life into the scenery, Rapid City basks in the sunshine, setting the stage for a bright and lively summer ahead.
As spring blossoms into summer, Rapid City experiences a notable shift in its weather patterns. May sees a 41% chance of sunny weather, which is lower than in preceding months like March and April, where the sun shines more frequently. This decline marks a transition into the warmer season, evidenced by the substantial increase in sunny days observed in June (67%) and July (63%). Overall, while May may have fewer sunny days compared to the early spring months, it serves as a precursor to the bright, vibrant days of summer, inviting residents and visitors alike to embrace the upcoming seasonal warmth.
As spring transitions into summer, Rapid City experiences a notable increase in daylight duration, culminating in May with an impressive 14 hours of sunlight. This month marks a significant leap from April, where daylight lasts for 13 hours. Following May, the trend peaks in June and July at 15 hours, offering long, sun-soaked days perfect for outdoor adventures. However, as summer winds down, daylight diminishes gradually, with August seeing a drop to 13 hours, and September further declining to 12 hours. The decline continues into fall and winter, with daylight dwindling to just 8 hours by December. This pattern showcases the rhythmic ebb and flow of light throughout the year, offering Rapid City residents a vibrant tapestry of seasonal change.
In Rapid City, May brings a gentle breeze with an average wind speed of 3.4 m/s (8 mph), slightly lower than the earlier spring months of January through April, which all hover around or just above 4.0 m/s. This subtle shift marks the transition into late spring, where the winds become more subdued as nature begins to flourish in full bloom. Interestingly, the wind speeds in May mirror those seen in June and September, suggesting a consistent pattern of mild breezes as summer approaches. As the year progresses, the wind speeds generally stabilize around the 3.2 to 4.0 m/s range, reinforcing the region's characteristic gentle winds that complement its beautiful landscapes. With the arrival of warmer weather, residents and visitors alike can enjoy the refreshing gusts while savoring the stunning surroundings that make Rapid City a captivating destination.
The weather in Rapid City changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of May's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Rapid City and find detailed weather information for every month.
May and January present stark contrasts in weather patterns. In May, temperatures can range from a chilly -4°C (24°F) at night to a warm high of 30°C (86°F) during the day, with an average temperature of 11°C (53°F). The month typically experiences around 112 mm (4.4 in) of precipitation over 17 days, contributing to the higher humidity levels at 74%. In contrast, January brings much colder conditions, with nighttime lows plunging to -26°C (-14°F) and daytime highs only reaching 16°C (61°F), resulting in an average temperature of -3°C (27°F). Precipitation is minimal in January, with only 14 mm (0.5 in) recorded over 4 days and humidity slightly lower at 73%. For more detailed insights into January weather, check out Rapid City weather in January.
Comparing the weather in May and February reveals stark differences in temperature and precipitation patterns. May experiences a much milder climate with average temperatures around 11°C (53°F) and a maximum of 30°C (86°F), while February sees much colder conditions, with averages around -6°C (22°F) and minimums plunging to -29°C (-19°F). Additionally, May is characterized by significantly higher precipitation, with 112 mm (4.4 in) over 17 days, compared to February's 27 mm (1.1 in) over just 7 days. Humidity levels are slightly higher in February at 78%, though May's humidity of 74% still contributes to its overall warmth. For more detailed weather insights, check out Rapid City weather in February.
When comparing the weather in March and May, there are notable differences in temperature and precipitation. March tends to be much colder, with average temperatures around 2°C (36°F), reaching a minimum of -26°C (-14°F), while May offers a milder climate with average temperatures of 11°C (53°F) and maximums soaring up to 30°C (86°F). Additionally, May experiences more precipitation, totaling 112 mm (4.4 in) over 17 days, compared to March's 44 mm (1.7 in) over just 8 days. Humidity levels also rise in May, averaging 74%, compared to March's 64%. For a closer look at March weather, you can visit Rapid City weather in March.
In comparing the weather between April and May, we see a significant warming trend as spring progresses. May boasts a broader temperature range with a minimum of -4°C (24°F) and an average of 11°C (53°F), peaking at 30°C (86°F). In contrast, April experiences cooler temperatures, with a minimum of -16°C (3°F) and an average of 5°C (41°F), reaching a maximum of 25°C (77°F). Additionally, May sees increased precipitation, totaling 112 mm (4.4 in) over 17 days, compared to April's 73 mm (2.9 in) across 11 days. Humidity levels also rise in May to 74%, up from April's 66%. For more details on April's weather specifics, check out Rapid City weather in April.
May and June offer contrasting weather conditions, with June generally being warmer and drier. In May, temperatures range from a low of -4°C (24°F) to a high of 30°C (86°F), with an average of 11°C (53°F) and substantial precipitation of 112 mm (4.4 in) over 17 days. Humidity sits at a moderate 74%. In contrast, June sees temperatures that start at a minimum of 4°C (40°F) and reach a maximum of 36°C (97°F), averaging 19°C (67°F). The precipitation in June decreases to 72 mm (2.8 in) over 13 days, and humidity increases slightly to 84%. For more detailed information, check Rapid City weather in June.
In May, the weather in Rapid City is characterized by a significant range in temperatures, with minimums dipping to -4°C (24°F) and maximums reaching up to 30°C (86°F). The average temperature sits around 11°C (53°F), accompanied by a notable 112 mm (4.4 in) of precipitation over 17 days and a humidity level of 74%. In contrast, July experiences warmer conditions, with minimum temperatures at 9°C (49°F) and highs soaring to 38°C (100°F). The average temperature increases to 22°C (72°F), while total precipitation decreases slightly to 96 mm (3.8 in) over 16 days, bringing a higher humidity level of 85%. For more details on the July weather, you can check Rapid City weather in July.
May and August present quite distinct weather patterns. In May, temperatures can range from a chilly -4°C (24°F) to a balmy 30°C (86°F), with an average of 11°C (53°F). The month experiences relatively high precipitation, with about 112 mm (4.4 in) spread over 17 days, leading to a humidity level of 74%. In contrast, August typically delivers warmer conditions, with minimum temperatures around 7°C (44°F), average highs of 20°C (69°F), and peaks reaching 37°C (98°F). There’s significantly less rainfall in August, totaling 57 mm (2.2 in) over 12 days, and the humidity rises to 85%. For more detailed information, you can check Rapid City weather in August.
May and September exhibit distinct weather patterns, reflecting the transition between spring and fall. In May, temperatures range from a chilly -4°C (24°F) to a warm 30°C (86°F), with an average of 11°C (53°F) and a higher precipitation level of 112 mm (4.4 in) over 17 days, resulting in a humidity of 74%. Conversely, September experiences a broader temperature range from -4°C (26°F) to a hotter max of 37°C (100°F), with an average temperature of 16°C (62°F). This month sees significantly less rainfall at 43 mm (1.7 in) over just 7 days, and a slightly higher humidity of 76%. For more detailed weather insights, you can visit Rapid City weather in September.
In comparing the weather of May and October, one can observe distinct differences and some similarities. May typically sees a broader range of temperatures, with a minimum of -4°C (24°F) and an average of 11°C (53°F), while the maximum can reach up to 30°C (86°F). In contrast, October experiences lower minimum temperatures, dipping to -18°C (-1°F) on average, although it shares the same maximum of 30°C (86°F) as May on rare occasions. Additionally, May is wetter, with 112 mm (4.4 in) of precipitation over 17 days compared to October's 52 mm (2.0 in) spread across only 8 days. Humidity levels remain quite similar, hovering around 74% in May and 71% in October. For a closer look at the weather patterns specific to October, visit Rapid City weather in October.
May and November present quite different weather patterns. In May, temperatures range from a chilly minimum of -4°C (24°F) to a warm maximum of 30°C (86°F), with an average of 11°C (53°F). The month experiences increased precipitation, averaging 112 mm (4.4 in) over approximately 17 days, and humidity levels sit at 74%. In contrast, November sees much colder temperatures, ranging from a minimum of -19°C (-2°F) to a maximum of 24°C (75°F), with an average of just 3°C (37°F). Precipitation is significantly lower at 17 mm (0.7 in) over 5 days, and humidity remains similar at 73%. For a closer look at what to expect during this colder month, you can visit Rapid City weather in November.
May and December present stark contrasts in weather. In May, temperatures range from a brisk -4°C (24°F) at night to a warm 30°C (86°F) during the day, with an average of 11°C (53°F). This month also sees considerable rainfall, with 112 mm (4.4 in) spread over 17 days, alongside a relatively high humidity level of 74%. In contrast, December experiences much colder conditions, with nighttime lows plummeting to -23°C (-10°F) and daytime highs only reaching up to 21°C (70°F), averaging around -1°C (30°F). Rainfall is minimal in December, totaling just 28 mm (1.1 in) over six days, with a humidity level of 75%. To explore more about what to expect during December, you can visit Rapid City weather in December.
As May arrives in Rapid City, the weather transitions into a warm and vibrant period, characterized by noticeably higher temperatures compared to the cooler spring months. While the average temperature begins to rise, bringing a refreshing warmth, the likelihood of precipitation also increases, with rain appearing on roughly half of the days. This combination of warmth and humidity creates a dynamic climate, marking a significant departure from the chill of earlier months. For a deeper dive into how May compares to the rest of the year, explore our detailed page on Rapid City Climate.