Harman US

Firestone, CO Weather & Growing Conditions

Today
76°F
Mostly Sunny then Chance Showers And Thunderstorms
A chance of showers and thunderstorms between noon and 3pm, then showers and thunderstorms likely. Mostly sunny. High near 76, with temperatures falling to around 70 in the afternoon. East northeast wind 2 to 8 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Today 76°F Mostly Sunny then Chance Showers And Thunderstorms 2 to 8 mph ENE 63%
Tonight 51°F Chance Showers And Thunderstorms then Partly Cloudy 2 to 7 mph SSE 40%
Sunday 71°F Partly Sunny then Chance Showers And Thunderstorms 2 to 7 mph NE 29%
Sunday Night 49°F Chance Showers And Thunderstorms then Partly Cloudy 1 to 7 mph NNE 30%
Monday 73°F Mostly Sunny 1 to 8 mph NNE 1%
Monday Night 50°F Slight Chance Showers And Thunderstorms then Partly Cloudy 2 to 8 mph ESE 23%
Tuesday 75°F Mostly Sunny 5 mph NNE 4%
Tuesday Night 52°F Slight Chance Showers And Thunderstorms then Partly Cloudy 6 mph SSW 18%
Wednesday 78°F Mostly Sunny 2 to 6 mph NE 7%
Wednesday Night 52°F Slight Chance Showers And Thunderstorms then Mostly Cloudy 2 to 6 mph NW 15%
Thursday 79°F Mostly Sunny 2 to 7 mph N 5%
Thursday Night 54°F Partly Cloudy 2 to 7 mph SSW 12%
Friday 80°F Mostly Sunny 1 to 7 mph SSE 9%
Friday Night 54°F Slight Chance Rain Showers then Partly Cloudy 6 mph S 15%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Firestone, CO

Last spring frost
May 7
First fall frost
Oct 5
Growing season
151 days
Hardiness zone
5b

Explore more for Firestone, CO: full frost dates · planting calendar · Colorado frost dates

Climate data from the nearest NOAA station, Longmont 2 Ese, Co (8.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.