Weather

View from Look Rock Observation Tower. Lighting strikes, illuminating the mountains and sky of clouds in a purple hue.
The Look Rock webcam on the western edge of the park captured a photo of a lightning strike during a spring storm. Severe storms, including tornados, occur in the park, especially during spring and summer.

NPS Photo by Look Rock Webcam

 
 
 

Loading weather forecast...

 

Loading weather forecast...

 
 
Purple and white flowers growing low to the ground.
Common wildflowers in the Smokies: trillium, fringed phacelia, and phlox.

Thom McManus

Spring

March through May brings unpredictable weather. Changes occur rapidly - sunny skies can yield to snow flurries in a few hours.

  • Snow can fall at any time during March, particularly in the higher elevations. Temperatures in the lower elevations have a mean high of 61ºF. Low temperatures, which are often below freezing, have a mean of 42ºF.
  • By mid-April, the weather is usually milder with daytime temperatures in the 70s and occasionally the 80s. Below freezing temperatures at night are uncommon in the lower elevations but still occur higher up.
  • April averages over 4 inches (10.2 centimeters) of rain, usually in the form of afternoon showers.
  • May is warmer, with daytime highs in the 70s and 80s and lows in the 40s and 50s. May rainfall averages about 4.5 inches (11.4 centimeters).
 
A view of rolling mountains that appear blue-colored from atop a lush, grassy area with several evergreen trees.
Andrews Bald, reached via the Forney Ridge Trail, boasts sweeping views.

Andrea Walton

Summer

June through August means heat, haze, and humidity. Afternoon showers and thunderstorms are common.

  • Temperatures increase through the period with July and August afternoon highs in the 90s in the lower elevations. Evening lows are usually comfortable with readings in the 60s and 70s. In the higher elevations, the weather is much more pleasant.
  • On Mount Le Conte (6,593 feet/2,010 meters high), temperatures above 80 degrees Fahrenheit are extremely rare.
 
A mountain ridge full of orange, yellow, and red fall colors sprinkled with evergreen trees. Bright orange trees are in the foreground and rolling mountains are in the background.
Mt. Sterling as seen from Mt. Cammerer in fall.

Bob Carr

Autumn

September through mid-November welcomes cooler weather that signals the onset of the fall color season. Warm days alternate with cool nights.

  • Daytime highs are usually in the 70s and 80s during September, falling to the 50s and 60s in early November.
  • The first frosts often occur in late September. By November, the lows are usually near freezing. This is the driest period of the year with only occasional rain showers. In the higher elevations, snow is a possibility by November.
 
A flowing creek with snow-covered rocks sprinkled in it and snowy trees lining its banks.
A view along the Little River Trail in winter.

Bob Carr

Winter

Mid-November through February is generally moderate, but weather extremes do occur, especially with an increase in elevation. It is not unusual to have warm temperatures in the low elevations and snow in the higher areas.

  • About half the days in the winter have high temperatures of 50 degrees or more. Highs occasionally even reach the 70s.
  • Most nights have lows at or below freezing, but lows of -20°F are possible at high elevations. In the low elevations, snows of 1" or more occur 1-5 times a year. Snow falls more frequently in the higher mountains and up to two feet can fall during a storm.
  • One is most likely to find snow in the mountains in January and February.
 

Average Monthly Temperatures & Precipitation


The following tables give monthly averages for weather in the park. Temperatures are in degrees Fahrenheit. Precipitation and snow are listed in inches. T = trace.


For Gatlinburg, TN (low elevation)
Month

High

Low

Monthly Precipitation

Monthly Snowfall

Days of Precipitation

Jan

51

28

4.8"

2.3"

9

Feb

54

29

4.8"

2.9"

9

March

61

34

5.3"

T

8

April

71

42

4.5"

0

8

May

79

50

4.5"

0

9

June

86

58

5.2"

0

9

July

88

59

5.7"

0

10

Aug

87

60

5.3"

0

10

Sept

83

55

3.0"

0

5

Oct

73

43

3.1"

T

6

Nov

61

33

3.4"

0.7"

7

Dec

52

28

4.5"

1.0"

8



For Clingmans Dome (high elevation)
Month

High

Low

Monthly Precipitation

Monthly Snowfall

Days of Precipitation

Jan

35

19

7.0"

18"

12

Feb

35

18

8.2"

20"

12

March

39

24

8.2"

26"

12

April

49

34

6.5"

5"

10

May

57

43

6.0"

T

10

June

63

49

6.9"

0

11

July

65

53

8.3"

0

13

Aug

64

52

6.8"

0

12

Sept

60

47

5.1"

T

8

Oct

53

38

5.4"

2"

8

Nov

42

28

6.4"

5"

9

Dec

37

21

7.3"

8"

10

 

Drought

Keetch and Byram (1968) designed a drought index specifically for fire potential assessment. It is a number representing the net effect of evapotranspiration and precipitation in producing cumulative moisture deficiency in deep duff and upper soil layers. It is a continuous index, relating to the flammability of organic material in the ground.

The KBDI attempts to measure the amount of precipitation necessary to return the soil to full field capacity. It is a closed system ranging from 0 to 800 units and represents a moisture regime from 0 to 8 inches of water through the soil layer. At 8 inches of water, the KBDI assumes saturation. Zero is the point of no moisture deficiency and 800 is the maximum drought that is possible. At any point along the scale, the index number indicates the amount of net rainfall that is required to reduce the index to zero, or saturation.

The inputs for KBDI are weather station latitude, mean annual precipitation, maximum dry bulb temperature, and the last 24 hours of rainfall. Reduction in drought occurs only when rainfall exceeds 0.20 inch (called net rainfall). The computational steps involve reducing the drought index by the net rain amount and increasing the drought index by a drought factor.

  • KBDI = 0 - 200: Soil moisture and large class fuel moistures are high and do not contribute much to fire intensity. Typical of spring dormant season following winter precipitation.

  • KBDI = 200 - 400: Typical of late spring, early growing season. Lower litter and duff layers are drying and beginning to contribute to fire intensity.

  • KBDI = 400 - 600: Typical of late summer, early fall. Lower litter and duff layers actively contribute to fire intensity and will burn actively.

  • KBDI = 600 - 800: Often associated with more severe drought with increased wildfire occurrence. Intense, deep burning fires with significant downwind spotting can be expected. Live fuels can also be expected to burn actively at these levels.

Last updated: July 7, 2023

Park footer

Contact Info

Mailing Address:

107 Park Headquarters Road
Gatlinburg, TN 37738

Phone:

(865)436-1200

Contact Us