Also the WoTC does not clarify it, in fact in Metarra's entry there we can read "Her strength level was 9(4), roughly equal to Elayne and Egwene". But we know firstly that both of them have a potential at level 8(5) and secondly that Egwene was forced and so reached it, but instead Elayne has to reach her full potential yet.
She Travels with the the rest of the group led by Nynaeve al'Meara and Elayne Trakand from Ebou Dar to the Kin's farm with the Bowl of the Winds. Due to her great strength in the One Power, she is part of the thirteen women who link and channel into the Bowl of the Winds to change the weather.
After it Metarra reaches Caemlyn, following Elayne and Nynaeve, along the other Windfinders. In the capital city of Andor, for a while Metarra is instructed by the Aes Sedai along her fellow companions. Some time later, when Zaida leaves Caemlyn, Metarra goes with her.