Reliability of SSD vs HDD (Over large temperature variations)

Look for an industrial or ruggedized SSD for this application.

A good example of a proper product spec.
http://www.pretec.com/products/ssd-series/item/sata-ssd-series/a5000-industrial-grade

．Standard 2.5" SATA III SSD, compatible with SATA III/II/I interface
．Capacity: 32GB ~ 256GB
．Data transfer rate: Up to 490 MB/s
．Built-in ECC (Error Correction Code) function
．Support ATA-8 command and SMART function
．Temperature
I.  Operating Temperature: 0℃ ~ +70℃
II. Extended Temperature: -40℃ ~ +85℃
III. Storage Temperature: -55℃ ~ +95℃