I don’t wear a hat daily, but I wear a hat when I need to.
Out of all the types of hats, the absolute most useless one ever to exist is the baseball hat. At best, a baseball hat will maybe provide a little shade for your eyes. It will not keep sun/rain/snow off your head, neck, or ears. It is a piece of athletic gear that has little use outside of athletic endeavors. OK, got that out of my system.
Second major whining point – civilized men do not wear hats indoors! There are a few exceptions such as color guards and some assignments but if you can’t take your cover off when you cross a threshold, I will pass judgement on you.
A good felt hat with a real brim will work in most cool, cold, dry or damp weather. The style is up to you, but a good basic fedora will fit into most situations and is useful. Felt is not ideal in heavy rain or hot weather. A good dark gray fedora can pass for a stylish hat and still be useful as a casual hat. Cowboy hat styles are varied and sometimes work in formal situations but can look a little too “rural” in some settings. You must make that call yourself.
Hot weather and bright sun dictate something that breathes but provides shade. These are seldom situations that require a lot of style, and the standards get relaxed a bit in hot weather. Think Panama hats, think straw type campaign hats, think material that doesn’t get sweat stained easily.
While not suitable in formal settings but entirely adequate in casual settings, the Tilley model T4 is extremely useful. It provides shade. It keeps moderate rain off your head. It keeps snow off your head, and it isn’t too hot. It’s not a sophisticated hat for formal settings, so not the best “out on the town” hat, but very useful in a lot of situations and fits into casual situations well.
A Gore-Tex floppy boonie hat is as ugly as a mud fence but it the BEST thing in the world in heavy rain. And you can stuff it in your raincoat pocket when you walk indoors. Boonie hats are not stylish in any stretch of imagination but they are great in foul weather.