Running show timezone; will reveal the timezone for your postgres
connection. If you want to change the timezone for the duration of the
connection, you can run something like
> set timezone='America/New_York';
SET
> show timezone;
TimeZone
------------------
America/New_York
(1 row)
Now, if you run a command such as select now();, the time will be in
Eastern time.
h/t Jack Christensen