The onset of the monsoon rains in India coincides with the middle of summer. Metoro probably had heard some version of the myth about the great ocean god Varuna, and he - presumably correctly - connected Aa6-66 with the 'deluge of rain' at the number of the beast:

Aa6-64	Aa6-65	Aa6-66	Aa6-67	Aa6-68	Aa6-69	Aa6-70
i to moa	ko te vai hopu o te moa	e he goe kua moe	ki to vaha o to ika mea	o te maitaki	kua noho te ariki	e mago

The following imbalanced state of nature seems to be illustrated in Aa6-68 - at left (past) a high sky and at right (forward in time) the low space left up to the sky roof resulting from the 'high tide'.

The moa (Aa6-64) has got his vai hopu (water to bathe in), Aa6-65. By way of his ordinal number, 6-64, he is related to day number 6 * 64 / 2 = 6 * 32 = 192 (= the number of glyphs in the K text). The first half of the year is ending and the dry earth is being inundated by the 'Flood'. The 6th Rain God station describes the situation:

Also according to the Maya all the torrents of water originated from the Milky Way. The picure below (from Maya Cosmos) identifies the source as the 'Cosmic Dragon':