Convert Timestamp from PostgreSQL to Time Zone in Query (Rails) - ruby-on-rails

Question

Past the hours of head-banging for this one.
I am attempting to separate the query model from PG for the model start_time (stored in UTC) by day group.
Morning (12a - 12p)
Afternoon (12p - 5p)
Evening (5p - 12a)
I've tried scope methods, queries by instance methods, and overall class methods. All of which return the day group by UTC (not the local time zone for the scheduled event)
# event.rb
def self.morning
startday = 0
midday = 12
Event.where("extract(hour from start_time) >= ? AND extract(hour from start_time) < ?", startday, midday)
end
Also tried,
def self.afternoon
midday = "12:00:00"
eveday = "17:00:00"
Event.where("start_time::time >= ? AND start_time::time < ?", midday, eveday)
end
When console prompting (and generally throughout the app) I call event.start_time is successfully returned in the local time zone (set in the application.rb file)
But unless called outside of the model, the start_time continues to query as UTC.
I do not want to preset the DB timezone (as this is bad practice and the app is used globally)
Edit
As an example in the view, I am calling
<% events.morning.order("start_time ASC").each do |fit_class| %>
...
where,
events = #events = Event.all # passed through a partial

Answer 1

Just add scopes for Event model with time zone checks
class Event < ApplicationRecord
scope :morning, -> { where(
"start_time >= ? AND start_time < ?",
formatted_time(0), formatted_time(12))
}
scope :afternoon, -> { where(
"start_time >= ? AND start_time < ?",
formatted_time(12), formatted_time(17))
}
scope :evening, -> { where(
"start_time >= ? AND start_time < ?",
formatted_time(17), formatted_time(24))
}
private
def formatted_time(hour = 0)
Time.zone.parse(Date.current.to_s).change(hour: hour)
end
end
You don't have to modify any other time zone settings for this query. Hope it helps!

Answer 2

For onlookers, my temporary solution is as follows (MUCH research into the PostgreSQL docs):
def self.morning
startday = 0
midday = 12
Event.where("extract(hour from start_time - interval '6 hours') >= ? AND extract(hour from start_time - interval '6 hours') < ?", startday, midday)
end
def self.afternoon
midday = 12
eveday = 17
Event.where("extract(hour from start_time - interval '6 hours') >= ? AND extract(hour from start_time - interval '6 hours') < ?", midday, eveday)
end
def self.evening
eveday = 17
endday = 24
Event.where("extract(hour from start_time - interval '6 hours') >= ? AND extract(hour from start_time - interval '6 hours') < ?", eveday, endday)
end
This required me to preset the application time zone.
# application.rb
config.time_zone = "Central Time (US & Canada)"
I will change post the full-solution update when discovered!