Tempest provides a map of units around you. (actually expands to the US and CA which is cool) I use it for tracking differences in the surrounding areas. Your units are working in all areas except one. When installing the unit there is a blue arrow that must be facing north. I used a hand held compass to install mine. You can also use your phone. I see some units that are the exact opposite of mine in wind direction. I am registered with the Weather Underground so I have to be setup right all the time. This brings up another concern. In my area in the mid-Atlantic, following directions affords me the best angle with the sun to recharge the amazing battery in the unit. If you are having battery problems, pointing the black stripes (solar cells) to the south (in the northern hemisphere) gives you the greatest chance of keeping your unit batteries in top condition. Anyway, I love my unit.
Zoom and pan to see the whole globe.
Unless the unit is installed in the southern hemisphere, then it should point south. The app should automatically enable a 180° offset, but it can be manually set. Also, if you used a magnetic compass, hopefully you remembered to orient the Tempest to true North if there is any declination for your location.
If they aren’t right next to each other you can’t compare wind direction differences to determine proper orientation.
And for those who have issues due to tree shadows, weather, or are just too far north/south to have enough sun year round, there is the Power Booster Accessory for external power.