With such short distances, I would consider
Nanostations, simpler, smaller and cheaper than the Nanobridge. Put Click PLCs at each site with 4-20mA analog input modules and use signal converters for your temp sensors. If you like the 820, then use that instead of the Click. If it supports messaging over Ethernet, you should be able to use it with the Ubiquiti wireless gear to collect all the data at the main PLC that will connect to the cellular network.
If this is for alarm notifications, you might also want to stick a
CR3000 HMI at the master so that you have a window into the system and a very
flexible means of generating alarms and sending them to run-time configurable recipients.
In general, I like my analogs to be separate modules, but the stuff I deal with is often tower level sensors (pressure transmitters) that get hit by lightning, so swapping out a fried analog input card is easier than replacing a PLC with built in analogs. I used several of the
ProSense RTDs with plug-in transmitters and they are very installer friendly and not much more money than doing it the old fashioned way.
I also like the StrideLinx VPN units. I have 5 in the field now, and one of them is the Wifi model. I have not used their 4G model, but I believe it only works with AT&T.