Google announced a while ago that Chrome would begin alerting users when visiting a website that was unsecured and still on HTTP rather than HTTPS in July 2018 - and that time has come.
If your website is still an HTTP website and has forms, login fields or other forms of input, Google’s Chrome browser will begin marketing these as not secure.
Google has announced that later in 2017 they will be adding a new warning for searchers, which will mark websites as "not secure" if they haven't moved to HTTPS, and are still HTTP.
Google has been pushing for more secure websites across the internet for some time now, but now it's been said that 34% of all the sites within Google Search Results are now HTTPS.
Google is once again encouraging webmasters to adopt HTTPS, announcing that Chrome will display HTTP sites as unsecure in the future.