Casper, WY
Wyoming · Records since 1939–2026
Records for August 11
🔥 Record High
August 11, 2000
+11° from 88° normal❄ Record Low
August 11, 2004
-14° from 53° normalAll-Time Records — Casper
Top 10 Record Highs — August 11
| # | Temp | Date |
|---|---|---|
| 🏆 | 99°F | August 11, 2000 |
| 2 | 98°F | August 11, 2022 |
| 3 | 98°F | August 11, 2018 |
| 4 | 98°F | August 11, 2003 |
| 5 | 96°F | August 11, 1991 |
| 6 | 96°F | August 11, 1969 |
| 7 | 95°F | August 11, 2006 |
| 8 | 95°F | August 11, 1984 |
| 9 | 95°F | August 11, 1983 |
| 10 | 95°F | August 11, 1978 |
Top 5 Record Lows — August 11
| # | Temp | Date |
|---|---|---|
| 🥶 | 39°F | August 11, 2004 |
| 2 | 42°F | August 11, 2009 |
| 3 | 43°F | August 11, 1996 |
| 4 | 44°F | August 11, 2025 |
| 5 | 45°F | August 11, 1980 |
Heat Wave Summary — Casper
threshold: 94°F (90th percentile of historical Jun–Aug highs)2026 Daily High Temperature vs Normal
Year to date160 of 221 days with data were above the 1991–2020 normal high for their date.
Days ≥ 90°F Per Year
1940–2026Average Daily High by Decade
Full year · complete decades only
Longest Heat Waves — Casper
| # | Dates | Days | Peak | Avg High | Avg Overnight Low |
|---|---|---|---|---|---|
| 🏆 | Jul 10, 2026 – Jul 20, 2026 | 11 | 103°F (Jul 12) | 98°F | 57°F |
| 2 | Jul 15, 2007 – Jul 25, 2007 | 11 | 99°F (Jul 17) | 96°F | 59°F |
| 3 | Jun 23, 1990 – Jul 2, 1990 | 10 | 102°F (Jun 30) | 99°F | 57°F |
| 4 | Jun 25, 2002 – Jul 3, 2002 | 9 | 100°F (Jun 30) | 96°F | 53°F |
| 5 | Aug 6, 2003 – Aug 14, 2003 | 9 | 99°F (Aug 14) | 97°F | 60°F |
| 6 | Jun 20, 1988 – Jun 27, 1988 | 8 | 102°F (Jun 24) | 98°F | 65°F |
| 7 | Jul 3, 1989 – Jul 9, 1989 | 7 | 102°F (Jul 8) | 98°F | 58°F |
| 8 | Aug 2, 2001 – Aug 8, 2001 | 7 | 101°F (Aug 6) | 97°F | 62°F |
| 9 | Jul 19, 2014 – Jul 25, 2014 | 7 | 100°F (Jul 23) | 96°F | 55°F |
| 10 | Jul 19, 2005 – Jul 24, 2005 | 6 | 103°F (Jul 22) | 98°F | 58°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
2nd-warmest month on record
2nd-warmest July of 87 on record
+4.5° vs. 71.3° average (1991–2020)Longest 90°F Streak in July
20 consecutive days with highs of at least 90°F (Jul 10–29, 2026, peaking at 103°F)
The longest July streak in Casper’s recorded history.
Average July Temperature by Year
1940–2026 · 2026 highlighted
Warmest Julys on Record
| # | Year | Avg Temp |
|---|---|---|
| 1 | 1954 | 76.1°F |
| 2 | 2026 | 75.8°F |
| 3 | 2006 | 75.3°F |
| 4 | 2012 | 75.2°F |
| 5 | 1966 | 74.9°F |
| 6 | 2007 | 74.8°F |
| 7 | 1964 | 74.1°F |
| 8 | 1940 | 73.9°F |
| 9 | 2001 | 73.8°F |
| 10 | 2002 | 73.5°F |
Warmest Months on Record (Any Month)
| # | Month | Avg Temp |
|---|---|---|
| 1 | July 1954 | 76.1°F |
| 2 | July 2026 | 75.8°F |
| 3 | July 2006 | 75.3°F |
| 4 | July 2012 | 75.2°F |
| 5 | July 1966 | 74.9°F |
| 6 | July 2007 | 74.8°F |
| 7 | August 1983 | 74.7°F |
| 8 | July 1964 | 74.1°F |
| 9 | July 1940 | 73.9°F |
| 10 | July 2001 | 73.8°F |
Nearby Stations — July 2026
How the same month ranked at the closest reporting stations
| Station | Avg Temp | July Rank |
|---|---|---|
| Casper, WY | 75.8°F | 2nd of 87 |
| Lander, WY | 76.5°F | 1st of 135 |
| Sheridan, WY | 76.1°F | 2nd of 120 |
| Cheyenne, WY | 74.1°F | 3rd of 154 |
| Scottsbluff, NE | 79.1°F | 3rd of 130 |