Cuahuitl Ehua.

the name of a month of twenty days, also called Atl Cahualo; dedicated to the celebration of the rain deities, such as the Tlalocs and Chalchiuhtlicue
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2 -- The Ceremonies, No. 14, Part III, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1951), 1, 42.