Portland, TN Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Portland, a city in Sumner County, Tennessee.
Overnight
63°F
Showers And Thunderstorms
Showers and thunderstorms. Cloudy, with a low around 63. South southeast wind 15 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 100%. New rainfall amounts between three quarters and one inch possible.
7-day forecast for Portland
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 63°F | Showers And Thunderstorms | 15 to 20 mph SSE | 98% |
| Wednesday | 72°F | Showers And Thunderstorms | 5 to 20 mph SSW | 99% |
| Wednesday Night | 47°F | Partly Cloudy | 0 to 5 mph W | 0% |
| Thursday | 70°F | Mostly Sunny | 0 to 5 mph WSW | 0% |
| Thursday Night | 44°F | Patchy Fog | 0 mph | 0% |
| Friday | 65°F | Patchy Fog then Mostly Sunny | 0 to 10 mph NW | 0% |
| Friday Night | 39°F | Partly Cloudy | 5 mph NNW | 0% |
| Saturday | 57°F | Mostly Sunny | 5 mph N | 0% |
| Saturday Night | 33°F | Partly Cloudy | 0 to 5 mph N | 0% |
| Sunday | 58°F | Mostly Sunny | 0 to 5 mph N | 1% |
| Sunday Night | 33°F | Mostly Clear | 0 to 5 mph N | 1% |
| Monday | 61°F | Sunny | 0 to 5 mph SSW | 0% |
| Monday Night | 35°F | Clear | 0 mph | 1% |
| Tuesday | 66°F | Sunny | 0 to 5 mph WSW | 1% |
Forecast source: National Weather Service (api.weather.gov) for Portland (36.597, -86.527). Updated through the day.
Growing snapshot for Portland
Last spring frost
Apr 5
First fall frost
Nov 1
Growing season
210 days
Hardiness zone
7b
More local growing data for Portland: nearby ZIP 37148 weather · frost dates · planting calendar · Tennessee frost dates
Nearby towns & communities
Bethpage
Bransford
Castalian Springs
Cottontown
Gallatin
Graball
Hendersonville
Mitchellville
New Deal
Oak Grove
Shackle Island
Walnut Grove
Westmoreland
Climate data from the nearest NOAA station, Portland Sewage Plt, Tn (1.7 mi from Portland). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.