Cisco Catalyst 3650 series Command Reference Manual page 997

The internal temperature sensor in the device measures the internal system temperature and might vary
Note
±5 degrees C.
Examples This example sets 15 as the difference between the yellow and red thresholds:
Device(config)# system env temperature threshold yellow 15
Device(config)#
Command Reference, Cisco IOS XE Everest 16.5.1a (Catalyst 3650 Switches)
system env temperature threshold yellow
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