Won't be long before winter sets in, and we have contaminated runway reports in METARs, for anyone who wants to get the text books out early and swot up on those too!
By the way, "AUTO" means an automated report, as others have said. Also worth mentioning, though, that "AUTO" can come with other codes you wouldn't see if a human observer had generated the report, e.g. NDC (nill cloud detected), or NDV (non-directional visibility - the visibility has been detected automatically, but unlike a human observer who would check for variations in visibility in different directions, the automated observation makes no observation on what direction this visibility relates to)....
Sorry. I'll get my anorak and leave.....
FFF
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