tona.

Headword: 
tona.
Principal English Translation: 

to be warm, for the sun to shine (see Karttunen and Molina); for it to be hot or sunny (see Lockhart and Molina); or, to prosper (see Launey); it shines, he shines

IPAspelling: 
toːnɑ
Alonso de Molina: 

tona. (pret. otonac.) hazer calor o sol.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 149r. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

TŌNA to be warm, for the sun to shine / hacer calor o sol (M).
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 245.

Lockhart’s Nahuatl as Written: 

to shine, be hot. Class 1: ōtōnac.
James Lockhart, Nahuatl as Written: Lessons in Older Written Nahuatl, with Copious Examples and Texts (Stanford: Stanford University Press and UCLA Latin American Studies, 2001), 240.

Attestations from sources in English: 

in tona, in ceoa = there is heat, there is cold (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 6 -- Rhetoric and Moral Philosophy, No. 14, Part 7, 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, 1961), chapter 35, 193.

tōna = to prosper (impersonal: it is warm)
Michel Launey, An Introduction to Classical Nahuatl, translated and adapted by Christopher MacKay (Cambridge: Cambridge University Press, 2011), 75.

cujx tonaz: tlathujz = Perhaps he will cause the sun to shine, to dawn (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 6 -- Rhetoric and Moral Philosophy, No. 14, Part 7, 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, 1961), 189.

themes: 
Weather, Climate