Thermostat, WiFi, Z-Wave, or Zigbee, that does not require manufacturer's cloud server

In that scenario there are any number of other sources to get the outside temperature including some outdoor rated zwave and zigbee sensors up to and including whole weather stations, if you don’t want to use cloud even for weather information (I assume you don’t care about forecast).

I live in Colorado at 7000+ elevation. Humidity is a concern for me too. But even more than temperature, humidity tends to be fairly localized in individual rooms and the humidifiers run independently of what the outside humidity is. It doesn’t matter if the outside humidity is 5% or 50% (I’m not sure I’ve ever seen a humidity that high though, 40% is a really humid day here), if the room where my wife keeps her instruments is under 40%, the humidifier in that room needs to turn on. If the humidity remains low after turning on, I need an alert to remember to fill the tank. To do that, I need a sensor in the room. I don’t need it from where the thermostat is. Each room where we control humidity has a dumb humidifier controlled by a smart outlet.

To run these humidifier rules I use Threshold Alert and Open Reminder [4.0.0.0;4.9.9.9], one instance created to drive the humidifiers and another instance created to alert me when the humidity remains too low.

Each individual binding will often list those devices it is compatible with but I don’t know of any comprehensive list of devices that has ever been published. Maybe you are thinking of the Zwave database? That is used by the Zwave binding and it’s pretty extensive, but it’s only Zwave devices and does not include anything that uses other technologies.

There are literally tens of thousands of devices that are compatible with OH. Just building such a list would be a herculean task.