"Forecasted" or "forecast"

With authors writing in English as a second language increasingly predominating, especially in technical fields, irregular verbs get regularized. As an editor, should I give up the Canute-like** struggle against the oncoming tide of forecasted and the like?

** Yes, I know ... !

As editor? Of course not!

However, in this case, according to dictionary.com

verb, -cast or -cast·ed

both forms are correct.

So, it is a matter of style and it depends on guidelines you decide to enforce.

My advice:

• Never give up on your own stuff! Make it as good as it can be, in grammar, style and content.
• Stop bothering about other peoples' stuff. I call this "stop the tut"! - and try to stop myself from tutting when I see bad spelling or grammar. English evolves :)

I found that once I let go of spelling errors in facebook posts, texts, email etc - let alone public signage or notices! - I enjoyed life more. I might have an occasional chuckle to myself about bad grammar on a sign, and if someone asks, I'll always try to help. But I don't correct them.