February is the middle of the dry season. The swell picture is unchanged from January, small and from the north, and the lake wind is at its most insistent: the same offshore that holds a wave open all morning can also be enough to make the paddle out hard work on an exposed beach.
That is worth planning around rather than avoiding. The reefs on the Tola coast take offshore better than the open beaches do, and the coves around San Juan del Sur sit out of the worst of it. The water is at 25°C, the coolest reading of the Nicaraguan year, which in practice still means boardshorts.

