Signal Mountain, TN Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Signal Mountain, a town in Marion County, Tennessee.
Today
84°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms after 11am. Mostly sunny, with a high near 84. East wind 0 to 5 mph. Chance of precipitation is 40%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Signal Mountain
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Chance Showers And Thunderstorms | 0 to 5 mph E | 42% |
| Tonight | 68°F | Chance Showers And Thunderstorms then Partly Cloudy | 0 mph | 53% |
| Wednesday | 83°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 0 to 5 mph S | 62% |
| Wednesday Night | 68°F | Chance Showers And Thunderstorms | 0 mph | 53% |
| Thursday | 85°F | Chance Showers And Thunderstorms | 0 to 5 mph S | 48% |
| Thursday Night | 68°F | Chance Showers And Thunderstorms then Partly Cloudy | 0 to 5 mph S | 48% |
| Friday | 85°F | Mostly Sunny then Chance Showers And Thunderstorms | 0 to 5 mph S | 39% |
| Friday Night | 68°F | Chance Showers And Thunderstorms | 0 to 5 mph S | 39% |
| Saturday | 85°F | Chance Showers And Thunderstorms | 0 mph | 66% |
| Saturday Night | 69°F | Showers And Thunderstorms Likely | 0 mph | 66% |
| Sunday | 85°F | Chance Showers And Thunderstorms | 0 mph | 50% |
| Sunday Night | 69°F | Chance Showers And Thunderstorms then Partly Cloudy | 0 mph | 50% |
| Monday | 85°F | Chance Showers And Thunderstorms | 0 mph | 45% |
| Monday Night | 70°F | Chance Showers And Thunderstorms then Partly Cloudy | 0 mph | 45% |
Forecast source: National Weather Service (api.weather.gov) for Signal Mountain (35.144, -85.341). Updated through the day.
Growing snapshot for Signal Mountain
Last spring frost
Mar 31
First fall frost
Nov 6
Growing season
219 days
Hardiness zone
7b
More local growing data for Signal Mountain: nearby ZIP 37405 weather · frost dates · planting calendar · Tennessee frost dates
Nearby towns & communities
Griffith Creek
Jasper
Kimball
Monteagle
New Hope
Powells Crossroads
Sequatchie
South Pittsburg
Whiteside
Whitwell
Climate data from the nearest NOAA station, Lookout Mtn-Point Park, Tn (8.6 mi from Signal Mountain). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.