Mount Gretna, PA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Mount Gretna, a borough in Lebanon County, Pennsylvania.
Today
84°F
Mostly Sunny
Mostly sunny, with a high near 84. Northeast wind 1 to 5 mph.
7-day forecast for Mount Gretna
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Mostly Sunny | 1 to 5 mph NE | 0% |
| Tonight | 66°F | Mostly Cloudy | 5 mph SE | 4% |
| Wednesday | 83°F | Showers And Thunderstorms Likely | 3 to 7 mph E | 70% |
| Wednesday Night | 71°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 3 to 7 mph SE | 61% |
| Thursday | 88°F | Partly Sunny then Showers And Thunderstorms Likely | 5 to 9 mph S | 71% |
| Thursday Night | 72°F | Showers And Thunderstorms Likely | 2 to 8 mph S | 71% |
| Friday | 88°F | Mostly Sunny then Showers And Thunderstorms Likely | 2 to 7 mph SW | 68% |
| Friday Night | 70°F | Showers And Thunderstorms Likely then Chance Showers And Thunderstorms | 2 to 6 mph SW | 68% |
| Saturday | 86°F | Slight Chance Rain Showers then Chance Showers And Thunderstorms | 2 to 7 mph W | 52% |
| Saturday Night | 70°F | Chance Showers And Thunderstorms | 6 mph W | 52% |
| Sunday | 87°F | Mostly Sunny | 3 to 7 mph W | 12% |
| Sunday Night | 71°F | Partly Cloudy | 6 mph SW | 12% |
| Monday | 89°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 5 to 10 mph W | 19% |
| Monday Night | 70°F | Slight Chance Showers And Thunderstorms | 6 to 9 mph W | 19% |
Forecast source: National Weather Service (api.weather.gov) for Mount Gretna (40.246, -76.471). Updated through the day.
Growing snapshot for Mount Gretna
Last spring frost
Apr 20
First fall frost
Oct 25
Growing season
185 days
Hardiness zone
7a
More local growing data for Mount Gretna: nearby ZIP 17064 weather · frost dates · planting calendar · Pennsylvania frost dates
Nearby towns & communities
Annville
Avon
Campbelltown
Cleona
Cornwall
Fort Indiantown Gap
Fredericksburg
Hebron
Jonestown
Lebanon
Lebanon South
Mount Gretna Heights
Myerstown
Palmyra
Pleasant Hill
Quentin
Sand Hill
Schaefferstown
Timber Hills
West Myerstown
Climate data from the nearest NOAA station, Lebanon 2 W, Pa (6.3 mi from Mount Gretna). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.