Boise, ID
Idaho · Records since 1875–2026
Records for August 11
🔥 Record High
August 11, 2018
+12° from 92° normal❄ Record Low
August 11, 1985
-17° from 62° normalAll-Time Records — Boise
Top 10 Record Highs — August 11
| # | Temp | Date |
|---|---|---|
| 🏆 | 104°F | August 11, 2018 |
| 2 | 102°F | August 11, 2015 |
| 3 | 102°F | August 11, 2014 |
| 4 | 102°F | August 11, 1996 |
| 5 | 102°F | August 11, 1972 |
| 6 | 102°F | August 11, 1875 |
| 7 | 101°F | August 11, 1898 |
| 8 | 101°F | August 11, 1888 |
| 9 | 100°F | August 11, 2022 |
| 10 | 99°F | August 11, 1964 |
Top 5 Record Lows — August 11
| # | Temp | Date |
|---|---|---|
| 🥶 | 45°F | August 11, 1985 |
| 2 | 46°F | August 11, 1896 |
| 3 | 47°F | August 11, 1932 |
| 4 | 47°F | August 11, 1907 |
| 5 | 48°F | August 11, 1991 |
Heat Wave Summary — Boise
threshold: 98°F (90th percentile of historical Jun–Aug highs)2026 Daily High Temperature vs Normal
Year to date151 of 221 days with data were above the 1991–2020 normal high for their date.
Days ≥ 90°F Per Year
1875–2026Average Daily High by Decade
Full year · complete decades only
Longest Heat Waves — Boise
| # | Dates | Days | Peak | Avg High | Avg Overnight Low |
|---|---|---|---|---|---|
| 🏆 | Jul 8, 2024 – Jul 24, 2024 | 17 | 108°F (Jul 10) | 104°F | 72°F |
| 2 | Jun 27, 2021 – Jul 8, 2021 | 12 | 107°F (Jul 6) | 102°F | 73°F |
| 3 | Jul 12, 1960 – Jul 22, 1960 | 11 | 111°F (Jul 19) | 102°F | 66°F |
| 4 | Jul 19, 2006 – Jul 28, 2006 | 10 | 107°F (Jul 22) | 102°F | 70°F |
| 5 | Jul 23, 2018 – Aug 1, 2018 | 10 | 102°F (Jul 24) | 100°F | 68°F |
| 6 | Jun 26, 2015 – Jul 4, 2015 | 9 | 110°F (Jun 28) | 103°F | 71°F |
| 7 | Jul 19, 1931 – Jul 27, 1931 | 9 | 108°F (Jul 20) | 102°F | 68°F |
| 8 | Jul 15, 1998 – Jul 23, 1998 | 9 | 108°F (Jul 17) | 100°F | 65°F |
| 9 | Jul 15, 2003 – Jul 23, 2003 | 9 | 108°F (Jul 22) | 103°F | 68°F |
| 10 | Jul 21, 1994 – Jul 29, 1994 | 9 | 106°F (Jul 22) | 101°F | 68°F |
Heat Waves Per Year
Warm Summer Nights (Jun–Aug)
Nights where the overnight low exceeded the 1991–2020 normal low
Above-Normal Summer Nights Per Year
Average June–August Low by Decade
Overnight lows · complete decades only
Precipitation
Actual vs. 1991–2020 full-month and full-season normals
Monthly Precipitation — Last 24 Months
Blue = actual · dashed line = monthly normal
Annual Precipitation Per Year (1970–2026)
Blue = above average · tan = below average · gold = 2026 (partial)
Heavy Rain Days Per Year (≥ 1.0")
Compare year-to-year changes in days with heavy rainfall (≥ 1.0")
Month in Review — July 2026
Average temperature · July 2026
10th-warmest month on record
9th-warmest July of 149 on record
+3.9° vs. 77.1° average (1991–2020)Longest 90°F Streak in July
17 consecutive days with highs of at least 90°F (Jul 15–31, 2026, peaking at 104°F)
The longest July streak since 2024 (2 years). The July record is 31 days, set in 2021.
Average July Temperature by Year
1877–2026 · 2026 highlighted
Warmest Julys on Record
| # | Year | Avg Temp |
|---|---|---|
| 1 | 2021 | 83.8°F |
| 2 | 2007 | 83.1°F |
| 3 | 2024 | 82.5°F |
| 4 | 2017 | 81.6°F |
| 5 | 2006 | 81.5°F |
| 6 | 2013 | 81.5°F |
| 7 | 2023 | 81.4°F |
| 8 | 2012 | 81.3°F |
| 9 | 2026 | 81.0°F |
| 10 | 2014 | 81.0°F |
Warmest Months on Record (Any Month)
| # | Month | Avg Temp |
|---|---|---|
| 1 | July 2021 | 83.8°F |
| 2 | July 2007 | 83.1°F |
| 3 | July 2024 | 82.5°F |
| 4 | August 2022 | 81.9°F |
| 5 | July 2017 | 81.6°F |
| 6 | July 2006 | 81.5°F |
| 7 | July 2013 | 81.5°F |
| 8 | July 2023 | 81.4°F |
| 9 | July 2012 | 81.3°F |
| 10 | July 2026 | 81.0°F |
Nearby Stations — July 2026
How the same month ranked at the closest reporting stations
| Station | Avg Temp | July Rank |
|---|---|---|
| Boise, ID | 81.0°F | 9th of 149 |
| Ontario, OR | 79.8°F | 17th of 70 |
| Stanley, ID | 62.6°F | 4th of 62 |
| McCall, ID | 68.0°F | 6th of 103 |
| Baker City, OR | 69.0°F | 21st of 99 |