This is the cover that male junior officers wear. Similar ones are worn by senior officers and chief petty officers:
It is reasonably weatherproof. The gold strap is a chinstrap. In high winds, the wearer would loosen up the strap and slide it under his chin, in order to not lose his cover.
This is the cover that female junior officers wear. All women in the Navy wear similar ones:
The chinstrap doesn't do jack shit. It is as useless as a promise from a politician. Worse was that the cover is not anywhere near close to being weatherproof. If you got it good and wet, the damned sides would droop and there was fuck-all that could be done about it. Oh, you could try to starch it up or something, but it never looked right. So if you thought that the weather was going to be good and you left your plastic rain-cover at home, well, that was a hundred-buck mistake.
The good news is that those stupid covers for women may be going away.