Lake Geneva Weather: September
 |
Average Day Temperature: | 76.2°F |
|
Average Night Temperature: | 59.0°F |
|
Sea Water Temperature: | 50.2°F |
|
Number of Sunny Days: | 15 days |
| Sunshine Hours: | 11.8 - 13.1 hours | |
|
Number of Rainy Days: | 1 day |
| Precipitation Totals: | 0.8 in | |
| detailed information | ||
forecast
| Lake Geneva |
Temperature
| Lake Geneva |
Air Temperature in September, °F
The highest day temperature in September 2025 was 90°F. The lowest night temperature was 35°F. The average values for day and night temperatures during September were 77.9°F и 55.6°F respectivly.
Lake Geneva Water Sea Temperature in September, °F
The average sea surface temperature in September 2025 for Lake Geneva was 30.0°F. The maximum and minimum values were 30.0°F and 30.0°F respectively.
Most of the days in September are sunny but you can also expect cloudy and gloomy days.
Precipitation Totals in September, in
Precipitation total in September for Lake Geneva is 0.8 in.
The average wind speed in September is 8.3 mph. It makes September one of the most windless months of the year for Lake Geneva.
We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Lake Geneva in September is 8.2 hours.
Lake Geneva on the Weather Map
| Boston |  |
+96 |
| Chicago | |
+86 |
| Hawaii |  |
+82 |
| Houston |  |
+80 |
| Las Vegas |  |
+118 |
| Los Angeles | |
+100 |
| Maui | |
+78 |
| Miami | |
+96 |
| Myrtle Beach | |
+90 |
| New York | |
+104 |
| San Diego | |
+94 |
| San Francisco | |
+82 |
| Santa Monica | |
+82 |
| Sarasota | |
+96 |
| Tampa | |
+98 |
| 1800 |  |
102°F | SE 4 mph |
| 2100 |  |
90°F | W 7 mph |
| 0000 | |
80°F | W 6 mph |
| 0300 | |
72°F | W 4 mph |
| 0600 | |
70°F | W 3 mph |
| 0900 | |
80°F | W 5 mph |
| 1200 | |
88°F | NW 6 mph |
| 1500 | |
90°F | NW 6 mph |