Just how big can a snowflake get? It depends on what you mean by 'snowflake'
The Guinness World Record folks would have us believe in a 19th century snowflake more than a foot wide, but some scientists are skeptical.
https://www.npr.org/2023/12/25/1217356234/just-how-big-can-a-snowflake-get-it-depends-on-what-you-mean-by-snowflake