Most watched television station in the United States is in Spanish: KMEX in Los Angeles

So says a very short article:

KMEX's 6 00 p.m. newscast also recorded the largest number of total viewers in the nation, with 146,000. And its late-night news also led with 197,000 viewers.

On that note, isn't it about time for the Spanish Wikipedia to create a page on the station? Thus far it's only available in English.

That's not an implication that the Spanish Wikipedia isn't doing a good job though. If you look at the list of Wikipedias and check the number of edits (generally better than number of pages as a way to determine the quality of a Wikipedia), Spanish is in 4th place. Japanese is only a wee bit behind but that gap will probably grow over time given the fact that Spanish-speaking nations still have a ways to go in internet penetration and are increasing rapidly whereas Japan is nearly saturated. In numbers of users it's also in second place at almost a million, compared to 8 million users in English and almost 700,000 users for German, the next after Spanish.