Much of the Tokelau nature lore is based on shrewd observations of natural phenomena. Clouds traveling rapidly or fish jumping from the water (sumu, lautiapua) foretell strong winds which are dangerous for canoes. Still clouds indicate safe weather but little sailing breeze. When the sky shows small clouds “an arm's length in size” it is called te langi o atu, a bonito sky. The west wind, which brings the bonito close to the island, usually blows at this time. When the sky is red and solidly cloudy except for a few small breaks, it is called langi o teo (the sky of the teo fish). Orange reflection of the sunset in the clouds, common near the equator, is la sila fonu (the sun like a turtle's breastplate). When the south wind is chilled it is tafenga a le malu (the cooling freshet). Although this wind is refreshing it is dreaded for it is believed to bring death to some member of the population. Rain which makes the surface of the lagoon red or yellow also signifies death. A rainbow is nuanua.

Violent phenomena of nature were dreaded in ancient times. Close thunder (faitilitili) and distant thunder (tangulu) were thought to come from supernatural objects rolling about on the shelf (takataka) of the sky. Thunder and lightning (uila) bring out the ufu and kone fish that live in the coral of the lagoon.

An eclipse of the sun predicts some catastrophe. The sun is thought to lose its blood and become lifeless, ngase toto o te la (the sun's blood becomes like that of a sick person).

A full moon setting in a clear sky is an indication of calm weather. According to Turner (32) the ancient people believed that the moon was a residence of departed chiefs and that its waning (kaina te masina, the eating of the moon) was caused by its being eaten by the inhabitants. This was cause for great consternation and feasts and ceremonies were held. The name for an eclipse of the moon, which brings the atu and malau to the surface of the sea, suggests that this was explained in the same way as the waning moon.

Stars and constellations were used as guides in navigating among the islands and on voyages to Samoa. The following stars are remembered at Atafu as part of the old voyaging captains' lore of navigation.