Last updated: June 24, 2025
In Grand Island, United States, the average temperature in September hovers around 21°C (69°F), offering a pleasant backdrop for outdoor activities. However, be prepared for fluctuations, as temperatures can dip as low as 4°C (40°F) and soar up to 36°C (96°F). Rain is also in the mix, with an average precipitation of 59 mm (2.3 in) over 6 days, making it wise to pack an umbrella. The average humidity is 77%, so be ready for that tropical feel!
In September in Grand Island, the average temperature is 21°C (69°F). Maximums can reach 36°C (96°F), while minimums can drop as low as 4°C (40°F). This wide range of temperatures makes Grand Island an ideal destination for travelers seeking both warm and cool experiences during their visit.
In Grand Island in September, the precipitation amount is 59 mm (2.3 in) over the course of 6 days.
In Grand Island in September humidity is 77%. With an average temperature of 21°C (69°F), this humidity feels like a warm, enveloping blanket that clings to your skin, making outdoor activities both invigorating and somewhat sluggish for traveling.
In Grand Island in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Grand Island.
UV Risk Categories
Weather in Grand Island varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Grand Island, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -3°C (26°F) | 28 mm (1.1 inches) | 73% | moderate |
| February Weather | -4°C (26°F) | 19 mm (0.7 inches) | 81% | moderate |
| March Weather | 5°C (41°F) | 86 mm (3.4 inches) | 69% | high |
| April Weather | 10°C (50°F) | 56 mm (2.2 inches) | 71% | very high |
| May Weather | 16°C (62°F) | 147 mm (5.8 inches) | 80% | very high |
| June Weather | 24°C (75°F) | 89 mm (3.5 inches) | 83% | extreme |
| July Weather | 25°C (78°F) | 66 mm (2.6 inches) | 84% | very high |
| August Weather | 24°C (75°F) | 71 mm (2.8 inches) | 84% | very high |
| September Weather | 21°C (69°F) | 59 mm (2.3 inches) | 77% | very high |
| October Weather | 11°C (52°F) | 86 mm (3.4 inches) | 72% | high |
| November Weather | 5°C (41°F) | 21 mm (0.8 inches) | 80% | moderate |
| December Weather | -1°C (31°F) | 42 mm (1.6 inches) | 79% | moderate |