Jefferson, IA Weather & Growing Conditions
Overnight
43°F
Chance Rain Showers
A chance of rain showers. Cloudy. Low around 43, with temperatures rising to around 45 overnight. West northwest wind 10 to 15 mph, with gusts as high as 21 mph. Chance of precipitation is 40%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 43°F | Chance Rain Showers | 10 to 15 mph WNW | 39% |
| Wednesday | 50°F | Slight Chance Rain Showers then Cloudy | 13 mph W | 19% |
| Wednesday Night | 41°F | Cloudy then Chance Rain Showers | 10 mph WNW | 32% |
| Thursday | 53°F | Chance Rain Showers then Mostly Cloudy | 10 mph NW | 29% |
| Thursday Night | 37°F | Mostly Cloudy | 3 to 8 mph N | 3% |
| Friday | 51°F | Mostly Sunny | 5 mph N | 1% |
| Friday Night | 29°F | Partly Cloudy | 1 mph NNE | 0% |
| Saturday | 54°F | Mostly Sunny | 0 to 3 mph SSW | 0% |
| Saturday Night | 35°F | Mostly Clear | 2 mph W | 0% |
| Sunday | 60°F | Sunny | 5 mph W | 0% |
| Sunday Night | 37°F | Clear | 3 mph SW | 0% |
| Monday | 66°F | Sunny | 3 to 7 mph SW | 0% |
| Monday Night | 40°F | Mostly Clear | 3 mph WNW | 0% |
| Tuesday | 64°F | Mostly Sunny | 3 mph NNW | 0% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Jefferson, IA
Last spring frost
Apr 26
First fall frost
Oct 9
Growing season
164 days
Hardiness zone
5b
Explore more for Jefferson, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Jefferson, Ia (1 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.