Climate averages 1991–2020
Thornton weather
in June.
A warm, moderately wet month: the 3rd warmest and the 10th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
June is a warm month in Thornton: daytime highs average 25.9°C and nights cool to about 10.8°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 52 mm of rain on roughly 8 days, which makes June a moderately wet month (the 10th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 57 min on an average June day.
The nearest other city in this atlas is Westminster (Colorado), United States (7 km away). In June its highs average 26.1°C, about as warm as Thornton, with 52 mm of rain.
Among the 498 cities listed in the United States, Thornton ranks joint 328th of 498 for the warmest June highs and joint 164th of 498 for the driest June (rainfall, lowest first). The mean June high of those 498 cities is 27.9°C; Thornton is 2.0°C cooler than that mean.
From June to July, average highs rise by 3.3°C to 29.2°C, and monthly rainfall falls from 52 mm to 41 mm.
The annual picture
June in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Thornton climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 4.3°C-9.7°C | -9.7°C | 22 | 5.2 | 9.710 h |
| February | 5.7°C-8.7°C | -8.7°C | 23 | 5.9 | 10.711 h |
| March | 10.7°C-4.9°C | -4.9°C | 47 | 7.6 | 11.912 h |
| April | 14.4°C-0.4°C | -0.4°C | 70 | 9.9 | 13.213 h |
| May | 19.6°C5.3°C | 5.3°C | 82 | 11.0 | 14.414 h |
| June, selected | 25.9°C10.8°C | 10.8°C | 52 | 8.3 | 14.915 h |
| July | 29.2°C14.5°C | 14.5°C | 41 | 7.2 | 14.715 h |
| August | 28.0°C13.8°C | 13.8°C | 39 | 6.4 | 13.714 h |
| September | 24.0°C9.4°C | 9.4°C | 36 | 5.8 | 12.512 h |
| October | 16.6°C2.3°C | 2.3°C | 40 | 6.1 | 11.211 h |
| November | 9.4°C-4.9°C | -4.9°C | 30 | 5.9 | 10.010 h |
| December | 4.0°C-9.7°C | -9.7°C | 21 | 4.9 | 9.49 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
June in nearby cities
- Westminster (Colorado), United States in JuneUnited States · 7 kmHigh 26.1°C · Low 10.8°C · 52 mm rain
- Arvada in JuneUnited States · 12 kmHigh 25.9°C · Low 10.7°C · 52 mm rain
- Denver in JuneUnited States · 14 kmHigh 26.2°C · Low 10.9°C · 52 mm rain
- Aurora (Colorado), United States in JuneUnited States · 20 kmHigh 27.3°C · Low 12.4°C · 40 mm rain
- Lakewood in JuneUnited States · 20 kmHigh 26.0°C · Low 10.7°C · 52 mm rain
- Boulder in JuneUnited States · 30 kmHigh 25.6°C · Low 10.8°C · 77 mm rain
- Centennial in JuneUnited States · 33 kmHigh 25.8°C · Low 10.5°C · 57 mm rain
- Highlands Ranch in JuneUnited States · 35 kmHigh 25.7°C · Low 10.3°C · 57 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Thornton) is explained once on the Thornton year overview and on the Sources, method and limits page.
Denver, Lakewood and Westminster (Colorado), United States lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.