Herculaneum, MO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Herculaneum, a city in Jefferson County, Missouri.
Overnight
63°F
Patchy Fog
Patchy fog. Clear, with a low around 63. Northeast wind around 1 mph.
7-day forecast for Herculaneum
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 63°F | Patchy Fog | 1 mph NE | 0% |
| Tuesday | 88°F | Patchy Fog then Sunny | 0 to 3 mph SE | 0% |
| Tuesday Night | 66°F | Mostly Clear | 3 mph SE | 0% |
| Wednesday | 92°F | Sunny | 3 mph S | 6% |
| Wednesday Night | 70°F | Slight Chance Showers And Thunderstorms | 5 mph S | 56% |
| Thursday | 88°F | Showers And Thunderstorms Likely | 3 mph S | 65% |
| Thursday Night | 69°F | Chance Showers And Thunderstorms | 2 mph S | 47% |
| Friday | 88°F | Chance Showers And Thunderstorms | 2 mph SW | 47% |
| Friday Night | 69°F | Chance Showers And Thunderstorms | 2 mph SW | 39% |
| Saturday | 90°F | Chance Showers And Thunderstorms | 2 mph S | 39% |
| Saturday Night | 71°F | Mostly Clear | 3 mph S | 10% |
| Sunday | 93°F | Sunny | 2 to 6 mph SW | 7% |
| Sunday Night | 73°F | Mostly Clear | 5 mph S | 5% |
| Monday | 95°F | Sunny | 6 mph SW | 5% |
Forecast source: National Weather Service (api.weather.gov) for Herculaneum (38.258, -90.393). Updated through the day.
Growing snapshot for Herculaneum
Last spring frost
Apr 9
First fall frost
Oct 26
Growing season
197 days
Hardiness zone
7a
More local growing data for Herculaneum: nearby ZIP 63048 weather · frost dates · planting calendar · Missouri frost dates
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Raintree Plantation
Scotsdale
Summer Set
Climate data from the nearest NOAA station, Festus, Mo (2 mi from Herculaneum). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.