I like the hand wrought iron ones stuck on a post in the garden. Lightening is a violent and dangerous weather phenomenon that can kill and does. So, forget the lawn mowing, weeding, or other gardening chores when such storms are approaching. If your garden is fairly open, in a valley, or prone to severe thunderstorms, consider lightning rod protection for tall trees near your home, or if they are valuable. Consult an arborist for advice and price quotes.
Windsocks are attractive and can be used to gauge the direction and speed of wind.
Some of these are mini computers, storing information at certain intervals and for weeks at a time. If nothing else, if you garden and need to know a little about the weather, you might consider a thermometer mounted outside the house and a rain gauge. When mounting the thermometer, pick a location out of direct sun if possible in order to get the true temperature. The better thermometers have a sensor on a long cable, so you can put the thermometer inside and run the cable outside where desired. I really like the rain gauges that you can monitor and reset inside by means of a thin wire and battery-operated dial.