St. Ann Highlands, CO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for St. Ann Highlands, a community in Boulder County, Colorado.
Overnight
29°F
Partly Cloudy
Partly cloudy, with a low around 29. West wind around 3 mph.
7-day forecast for St. Ann Highlands
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 29°F | Partly Cloudy | 3 mph W | 1% |
| Wednesday | 46°F | Partly Sunny then Chance Snow Showers | 0 to 6 mph NNE | 33% |
| Wednesday Night | 28°F | Chance Snow Showers then Mostly Cloudy | 2 mph WNW | 33% |
| Thursday | 49°F | Sunny | 0 to 5 mph WSW | 0% |
| Thursday Night | 32°F | Mostly Cloudy | 2 mph WSW | 2% |
| Friday | 49°F | Slight Chance Rain And Snow Showers | 0 to 3 mph N | 24% |
| Friday Night | 29°F | Slight Chance Rain And Snow Showers then Mostly Clear | 0 to 5 mph WNW | 23% |
| Saturday | 52°F | Sunny | 0 to 8 mph N | 2% |
| Saturday Night | 30°F | Mostly Clear | 3 mph W | 0% |
| Sunday | 59°F | Sunny | 1 to 8 mph W | 0% |
| Sunday Night | 36°F | Mostly Clear | 8 mph W | 0% |
| Monday | 59°F | Sunny | 0 to 7 mph WNW | 0% |
| Monday Night | 36°F | Partly Cloudy | 0 to 3 mph W | 0% |
| Tuesday | 57°F | Mostly Sunny | 1 to 5 mph W | 1% |
Forecast source: National Weather Service (api.weather.gov) for St. Ann Highlands (39.987, -105.456). Updated through the day.
Growing snapshot for St. Ann Highlands
Last spring frost
Jun 5
First fall frost
Sep 16
Growing season
103 days
Hardiness zone
5b
More local growing data for St. Ann Highlands: nearby ZIP 80471 weather · frost dates · planting calendar · Colorado frost dates
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Climate data from the nearest NOAA station, Coal Creek Canyon, Co (3.3 mi from St. Ann Highlands). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.