Dawn formed very late, on February 10, and the last storm, Tropical Depression Isa, dissipated early, on April 19.

It strengthened to a Category 2 tropical cyclone (Australian scale) before dissipating, northwest of Brisbane on the South Pacific basin.

It continued its L movement while strengthening to a tropical cyclone before weakening due to the cold waters and wind shear.

On April 17, 1970, Apollo 13 was making its final descent over the splashdown zone when they spotted a weakening Helen as they were re-entering the Earth's atmosphere.

[1][2] The system was subsequently tracked by infrequent satelitte imagery, which revealed that it slowly completed a cyclonic loop near the Solomon Islands before curving back toward the southwest.