Boise weather in July
In July, Boise has daytime highs averaging 34 °C, nights around 18 °C, with 0.8 wet days. Figures are 1991–2020 climate normals.
- 33.6°C Average high
- 17.8°C Average low
- 0.8days Wet days
- 3mm Rainfall
- 15h Daylight
Daily temperatures through July
How July develops
Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.
| Days | Avg high | Avg low | Chance of rain |
|---|---|---|---|
| 1–10 July | 32.4 °C | 16.7 °C | 3 % |
| 11–20 July | 33.8 °C | 17.9 °C | 2 % |
| 21–31 July | 34.6 °C | 18.8 °C | 3 % |
- Average highs rise from 32.4 °C early in July to 34.6 °C by the end of it.
What to expect
| Measure | Typical July | Share of the month |
|---|---|---|
| Days above 25 °C | 30 of 31 | 96 % |
| Days above 30 °C | 26 of 31 | 84 % |
| Days below 0 °C | 0 of 31 | 0 % |
| Days with more than 1 mm rain | 0.8 of 31 | 3 % |
Conditions in July
| Measure | Average |
|---|---|
| Mean temperature | 26 °C |
| Record high (1991–2020) | 42 °C |
| Record low (1991–2020) | 8.8 °C |
| Relative humidity | 31 % |
| Wind speed | 17 km/h |
| Cloud cover | 21 % |
Where Boise ranks in July
| Ranking | Position | Value |
|---|---|---|
| The driest places in North America in July | 28thof 50 | 2.7 mm |
| The warmest places in North America in July | 41stof 50 | 34 °C |
July compared with the months around it
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| May | 22.6 °C | 31 mm | 49 % |
| June | 27.7 °C | 18 mm | 38 % |
| July | 33.6 °C | 3 mm | 21 % |
| August | 33.0 °C | 3 mm | 22 % |
| September | 27.2 °C | 11 mm | 28 % |
See all twelve months for Boise
- July is the warmest month in Boise.
- It is the 1st driest month of the year.
- It ranks 1st for least cloud cover.
- Days last about 15 hours from sunrise to sunset.
- It rains on 0.8 of 31 days — 3 % of the month.
- Nights are about 16 °C cooler than the middle of the day.
- The hottest July day on record since 1991 reached 42 °C, 8.4 °C above the usual daytime high.
Nearby destinations in July
| Destination | Avg high | Wet days |
|---|---|---|
| Boise | 34 °C | 0.8 |
| Salt Lake City | 33 °C | 3 |
QuestionsJuly in Boise, answered
How warm is Boise in July?
Daily highs average 34 °C and nights fall to about 18 °C, a spread of 16 °C between afternoon and dawn. That makes July the 1st warmest month of the year here.
Does it rain much in Boise in July?
July averages 3 mm of rain, spread over about 1 of the 31 days — 3 % of the month. Cloud cover averages 21 % of the sky.
How long are the days in July?
Boise averages 15 hours between sunrise and sunset in July. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.
Data sources and method
- ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
- Open-Meteo — Open-Meteo.com. CC BY 4.0
- NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
- GeoNames — GeoNames.org. CC BY 4.0
- Normal period
- 1991–2020
- Dataset version
- era5-1991-2020-scores1.1
- Last processed
Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.
Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.