Temperature data logging

[Mike AA]

We have recently been asked to make a device to read temperatures of soil at increments of 1ft for 20ft logged hourly in a remote location over the course of the up coming winter months in sw Michigan. We will be using temperature probes with 2 conductor wiring for the temperature readouts, thats 21 probes we will be connecting, thats the easy part. The difficulty we have is what device (c-rio is a bit expensive to leave in the elements unmonitored) could we use with this many inputs. The data would have to be stored for upwards of 30 days at a time and the device relatively low power draw, solar panels will provide power for charging batteries and powering the device. Would something like an Aruindo work for this application with a breakout board? Could it save the data to a text file for later reading and not erase with a power loss?

Thanks for any help and suggestions!
Team 3458 Code Blue