Lake Bluff
Illinois, USA
Long-term weather forecast
Long-term weather forecast

September weather forecast and climate
Lake Bluff, IL

Ocean temperature

In Lake Bluff, Illinois, in September, the average water temperature is 68.5°F (20.3°C).
Note: For swimming, a surface water temperature of 68.5°F (20.3°C) is not enjoyable for the majority. It is not considered safe, as controlling breathing becomes progressively more difficult as water temperature decreases below 69.8°F (21°C).

Daylight

In September, the average length of the day in Lake Bluff is 12.5h.

How cold is the water in September in Lake Bluff?

In Lake Bluff, Illinois, the average seawater temperature in September is 68.5°F (20.3°C). Swimming in 68.5°F (20.3°C) is not enjoyable for the majority. Controlling breathing becomes progressively more difficult as surface water temperature decreases below 69.8°F (21°C).

How many hours of daylight does Lake Bluff have in September?

The average length of the day in September in Lake Bluff, Illinois, is 12.5h.
Average sea temperature in September - Lake Bluff, IL
  • Average sea temperature in September: 68.5°F

The best month for swimming (with the highest average sea temperature) is August (73.3°F).
The coldest month (with the lowest average sea temperature) is February (37.1°F).

Average daylight in September - Lake Bluff, IL
  • Average daylight in September: 12.5h

The month with the longest days is June (Average daylight: 15.2h).
The month with shortest days is December (Average daylight: 9.1h).