Summers in Las Vegas are scorching. The daily high averages around 38°C (100°F) from June to August, compared with average winter lows of around 13°C (55°F) from December to February; the rest of the year is temperate. It's pretty dry most of the time, but thunderstorms are most common in the summer (June to August) and can cause dangerous flash floods.
| Month | Temp (°C) | Rainfall (mm) | Humidity (%) | Sunshine (hours) |
| Jan | -2 - 16 | 18 | 8 | |
| Feb | 1 - 19 | 13 | 9 | |
| Mar | 4 - 22 | 8 | 10 | |
| Apr | 7 - 27 | 8 | 11 | |
| May | 11 - 32 | 5 | 12 | |
| Jun | 16 - 37 | 5 | 14 | |
| Jul | 20 - 39 | 13 | 12 | |
| Aug | 19 - 39 | 13 | 12 | |
| Sep | 14 - 35 | 8 | 12 | |
| Oct | 8 - 29 | 8 | 10 | |
| Nov | 2 - 22 | 5 | 9 | |
| Dec | -1 - 16 | 10 | 10 |