Boulder, CO Weather & Growing Conditions
Today
78°F
Patchy Smoke
Patchy smoke and a slight chance of rain showers before noon, then patchy smoke and a slight chance of showers and thunderstorms. Mostly sunny, with a high near 78. Northeast wind around 7 mph. Chance of precipitation is 20%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 78°F | Patchy Smoke | 7 mph NE | 17% |
| Tonight | 55°F | Patchy Smoke | 2 to 8 mph NNE | 11% |
| Wednesday | 86°F | Patchy Smoke | 2 to 7 mph NE | 1% |
| Wednesday Night | 58°F | Mostly Clear | 6 mph N | 1% |
| Thursday | 95°F | Sunny | 2 to 8 mph NNW | 1% |
| Thursday Night | 61°F | Clear | 3 to 7 mph WNW | 1% |
| Friday | 97°F | Sunny | 2 to 8 mph SSE | 0% |
| Friday Night | 65°F | Mostly Clear | 5 to 8 mph SSW | 0% |
| Saturday | 99°F | Sunny | 3 to 7 mph NNW | 3% |
| Saturday Night | 66°F | Partly Cloudy | 7 mph W | 0% |
| Sunday | 98°F | Sunny | 3 to 7 mph N | 9% |
| Sunday Night | 68°F | Partly Cloudy | 7 mph W | 4% |
| Monday | 97°F | Mostly Sunny then Chance Showers And Thunderstorms | 6 to 9 mph NNW | 30% |
| Monday Night | 66°F | Slight Chance Showers And Thunderstorms then Partly Cloudy | 3 to 9 mph W | 18% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Boulder, CO
Last spring frost
May 6
First fall frost
Oct 5
Growing season
151 days
Hardiness zone
6a
Explore more for Boulder, CO: full frost dates · planting calendar · Colorado frost dates
Climate data from the nearest NOAA station, Boulder, Co (3.3 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.