Mammoth Cave National Park in Kentucky features a humid subtropical climate with four distinct seasons. Summers are warm and muggy, while winters are short, cold, and sometimes snowy. The park is wet and partly cloudy year-round, offering lush forests, vibrant seasonal changes, and a consistent, cool underground climate that makes it a unique destination for outdoor and cave exploration.
The best times to travel section shows how the months compare for a visit, so you can find the time of year that fits what you want to do.
Background colours of the months:
The colour shows the typical temperature: yellow (hot), green (mild) and blue (cold). How strong the colour is shows the travel season: full colour means high season, soft colour means shoulder season and soft-striped means off season.
Weather symbols:
Each month has one symbol showing what the weather is typically like, such as hot and sunny, freezing or a rainy or snowy season. Use them to quickly spot months that match the weather you want, or to avoid the ones that don't.
Crowdedness:
The people icon shows how busy the place usually is. The more people, the more crowded it gets.
Additional notes:
The grey info boxes point out special things worth knowing, like recurring weather issues or seasonal events.
Mammoth Cave National Park experiences a moderate climate with warm, humid summers and cool, damp winters. Summer temperatures (June–August) typically range from 24–32°C (mid-70s to low 90s °F), with high humidity and frequent afternoon thunderstorms. The surface can feel sultry, but the cave remains a constant, cool 12°C (54°F) year-round, offering a welcome respite from the heat. Summer is also the park’s busiest season, with expanded cave tour options and all outdoor activities in full swing.
Spring (March–May) and autumn (September–November) are transitional, featuring mild to warm days (10–24°C in spring, 10–21°C in autumn), cooler nights, and vibrant displays of wildflowers or colourful foliage. Rain is common in both seasons, so waterproof gear is recommended. Autumn is especially popular for leaf-peeping in late October. Winters (December–February) are short and cold, with highs of 4–10°C and lows often below freezing. Snow and ice storms can occur, though snow cover is usually light and temporary. The park is quietest in winter, with fewer cave tours and reduced services, but the cave’s interior remains comfortably temperate. Annual precipitation averages around 1,270 mm (50 inches), spread fairly evenly throughout the year, with spring and winter being the wettest periods. Winds are generally light to moderate, but brisk gusts are possible during storms. Daylight varies from about 9 hours in winter to 15 hours in midsummer, supporting a long growing season and diverse wildlife.
| Average climate data for Mammoth Cave National Park, United States | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Average maximum temperature (°C) | 5 | 8 | 14 | 20 | 25 | 29 | 31 | 30 | 27 | 21 | 14 | 8 | 31 |
| Average minimum temperature (°C) | -5 | -4 | 2 | 7 | 12 | 16 | 19 | 18 | 14 | 7 | 2 | -2 | -5 |
| Average precipitation (mm) | 98 | 106 | 124 | 106 | 126 | 108 | 123 | 97 | 96 | 74 | 107 | 120 | 1,285 |
| Average rainfall days (days) | 11 | 11 | 13 | 11 | 12 | 10 | 11 | 9 | 8 | 8 | 10 | 12 | 126 |
| Average daily daylight hours (h) | 10 | 10 | 12 | 13 | 14 | 14 | 14 | 13 | 12 | 11 | 10 | 9 | 12 |
| Average daily sunshine hours (h) | 4 | 5 | 6 | 8 | 9 | 10 | 9 | 9 | 8 | 7 | 5 | 4 | 7 |
| Average UV index | 2 | 3 | 5 | 7 | 8 | 10 | 10 | 9 | 7 | 5 | 3 | 2 | 6 |
The best time to visit Mammoth Cave National Park is in spring (March–May) and autumn (September–early November). These seasons offer mild temperatures, fewer crowds than summer, and beautiful wildflowers or autumn foliage. Outdoor activities and cave tours are widely available, and the weather is generally comfortable for hiking and exploring both above and below ground.
The least favourable time to visit is in mid-winter (December–February), when cold, wet, and sometimes icy conditions can limit outdoor activities and reduce cave tour options. However, winter offers solitude and a unique, peaceful atmosphere for those prepared for chilly weather and fewer services.
The park has a humid subtropical climate with warm, muggy summers and short, cold winters. Rain falls year-round, and the cave maintains a constant cool temperature of 12°C (54°F), regardless of season.
Spring and autumn are best, offering mild weather, blooming wildflowers or autumn colours, and comfortable conditions for hiking and cave tours. Summer is busiest but can be hot and humid.
Snow and ice storms can occur in winter, but snow cover is usually light and temporary. Winter highs rarely exceed 10°C, and lows often drop below freezing.
Summer highs typically reach 24–32°C (mid-70s to low 90s °F), with high humidity and frequent afternoon thunderstorms. The cave remains a cool 12°C (54°F) year-round.
Pack layers for changing temperatures, a jacket for cave tours, waterproof gear for spring and autumn, and insect repellent for summer. Sturdy shoes are recommended for hiking and cave exploration.
Yes, but there are more tour options in summer. Winter offers fewer tours, but they are less crowded. Book in advance for spring and summer visits, as tours often sell out.
Summer is the busiest season, with crowded tours and full campsites. Spring and autumn are less crowded, while winter is quiet and offers solitude for those seeking a peaceful visit.
The warmest month, with the highest average maximum temperature, is July (31 °C). The month with the lowest average maximum temperature is January (5 °C). Overall, the average maximum temperature over the whole year is 19.3 °C.
The month with the highest average minimum temperature is July (19 °C). The coldest month, with the lowest average minimum temperature, is January (-5 °C). Overall, the average minimum temperature over the whole year is 7.2 °C.
The wettest month, with the highest amount of precipitation, is May (126.5 mm). The driest month, with the least amount of precipitation, is October (74.1 mm). Over the whole year there are 1,284.7 mm of rainfall on average.
The month with the most days of rain is March (13.1 days). The month with the fewest days of rain is October (7.9 days). Over the whole year there are 126.3 days of rain on average.
The month with the longest days, so the most daylight, is June (Average daylight: 14.1 h). The month with the shortest days, so the least daylight, is December (Average daylight: 9.1 h). Over the whole year there are 11.9 h of daylight per day on average.
The month with the most sunshine per day is June (Average sunshine: 10 h). The month with the least sunshine per day is December (Average sunshine: 3.9 h). Over the whole year there are 7 h of sunlight per day on average.
The months with the highest average UV index are June and July (UV index: 10). The months with the lowest average UV index are January and December (UV index: 2). Over the whole year the average UV index is 5.9.
