When running a node process on your machine locally, it will adopt your machine's local timezone.
I can observe this by starting a node process and outputting a date with
toLocaleString().
> new Date().toLocaleString()
'11/30/2020, 8:48:17 PM'This is the time that I'm writing this post, in Chicago (CST).
I can then start the process in another timezone, such as UTC.
$ TZ=utc nodeWith that node process, I can now do the same experiment.
> new Date().toLocaleString()
'12/1/2020, 2:52:40 AM'The time jumps ahead about 6 hours because it is going from CST (UTC-6) to UTC.
Similarly, I could start the Node process for the west coast like so,
$ TZ='America/Los_Angeles' node