You're right. I watched for about an hour, my jumps were up to 108 degrees Celsius.Same here.
CCR1009-7G-1C-1S+
S/N: 914F0A7D0752, 7AEC0624C572, 7AEC069DC199
This is not shown only in SNMP data, but also in Winbox - System - Health, when you look at counters long enough.