All it takes are a few days of sunshine and the lake water warms up quickly. I should rephrase that, the shallower smaller lakes warm up quickly, the bigger, deeper lakes take a little bit longer. On a calm day the surface temperatures are inviting while the deeper water remains much cooler.
The water temperature on Saganaga usually doesn’t get into the 70’s. Some smaller lakes in the BWCA will get into the 70’s but the average temperatures are in the upper 60’s. This isn’t warm when compared to a swimming pool because the average pool temperature is in the 80’s. Shallow lakes in other parts of the state might get that warm but not up here.
Then there’s Lake Superior that is so big and so deep that we rarely swim in it. Every once in awhile we’ll be brave and go for a dip near Grand Marais but it’s never for a long swim. As you can see from the maps below the temperature of the water is quite frigid. The good news is, it is warming up.
We have to make the most of the opportunity to go swimming because before we know it the water temperatures will begin a downward fall.