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Niwot, CO Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Niwot, a community in Boulder County, Colorado.

This Afternoon
57°F
Sunny
Sunny. High near 57, with temperatures falling to around 52 in the afternoon. East wind around 3 mph.

7-day forecast for Niwot

WhenTempForecastWindPrecip
This Afternoon 57°F Sunny 3 mph E 0%
Tonight 33°F Mostly Clear 3 mph SW 0%
Wednesday 56°F Partly Sunny 0 to 3 mph NNE 9%
Wednesday Night 33°F Mostly Cloudy 2 mph NW 9%
Thursday 59°F Sunny 1 to 5 mph SSE 0%
Thursday Night 34°F Partly Cloudy 2 mph WSW 1%
Friday 58°F Mostly Sunny 0 to 5 mph SSE 9%
Friday Night 33°F Mostly Clear 3 mph WSW 9%
Saturday 60°F Sunny 1 to 5 mph S 1%
Saturday Night 33°F Clear 3 mph WSW 0%
Sunday 67°F Sunny 3 mph SSW 0%
Sunday Night 39°F Mostly Clear 3 to 7 mph W 0%
Monday 67°F Sunny 1 to 5 mph E 0%
Monday Night 39°F Partly Cloudy 2 mph WNW 0%

Forecast source: National Weather Service (api.weather.gov) for Niwot (40.098, -105.158). Updated through the day.

Growing snapshot for Niwot

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

More local growing data for Niwot: nearby ZIP 80544 weather · frost dates · planting calendar · Colorado frost dates

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Climate data from the nearest NOAA station, Longmont 2 Ese, Co (6.8 mi from Niwot). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.