diff --git a/.github/workflows/jekyll-build.yml b/.github/workflows/jekyll-build.yml
index c79f55b937..5e170bd301 100644
--- a/.github/workflows/jekyll-build.yml
+++ b/.github/workflows/jekyll-build.yml
@@ -13,10 +13,5 @@ jobs:
         ruby-version: '3.0'
         bundler-cache: true
     - run: |
-        malformed_event_dates=$(grep -Er --files-without-match '^eventdate: [0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2} [-+][0-9]{4}$' _events)
-        if [ -n "${malformed_event_dates}" ]; then
-          echo "Malformed event date in:" >&2
-          echo "${malformed_event_dates}" >&2
-          exit 1
-        fi
+        bundle exec _scripts/_malformedevents.rb
         bundle exec jekyll build --future
diff --git a/Gemfile b/Gemfile
index 489b65fed6..ae42b12ef6 100644
--- a/Gemfile
+++ b/Gemfile
@@ -22,6 +22,10 @@ group :jekyll_plugins do
   gem "jekyll-sitemap"
 end
 
+group :test do
+  gem "activesupport"
+end
+
 # Windows and JRuby does not include zoneinfo files, so bundle the tzinfo-data gem
 # and associated library.
 platforms :mingw, :x64_mingw, :mswin, :jruby do
diff --git a/_events/_0000-0000-communitymeeting-template.markdown b/_events/_0000-0000-communitymeeting-template.markdown
index 1ff6243aac..2110834778 100644
--- a/_events/_0000-0000-communitymeeting-template.markdown
+++ b/_events/_0000-0000-communitymeeting-template.markdown
@@ -4,8 +4,7 @@
 eventdate: 2023-02-28 15:00:00 -0800
 title: OpenSearch Community Meeting - 2023-02-28
 online: true
-# If the event is online, remove the next line, otherwise uncomment and adjust it:
-# tz: Pacific/Tahiti
+tz: America/Los_Angeles
 signup:
     url: https://www.meetup.com/opensearch/events/290444926/
     title: Join on Meetup
diff --git a/_events/_0000-0000-dev-officehours-dashboards.markdown b/_events/_0000-0000-dev-officehours-dashboards.markdown
index 11959cfb08..17cb9cb6af 100644
--- a/_events/_0000-0000-dev-officehours-dashboards.markdown
+++ b/_events/_0000-0000-dev-officehours-dashboards.markdown
@@ -5,8 +5,7 @@ eventdate: 2023-05-05 10:00:00 -0700
 title: OpenSearch Dashboards Developer Office Hours - YYYY-MM-DD
 # if your event has an online component, put it here (mind the time-zone and daylight saving time!):
 online: true
-# If the event is online, remove the next line, otherwise uncomment and adjust it:
-# tz: Pacific/Tahiti
+tz: America/Los_Angeles
 # This is for the sign up button
 signup:
     # the link URL
diff --git a/_events/_sample.markdown b/_events/_sample.markdown
index 8fbc8907b4..0f980858c0 100644
--- a/_events/_sample.markdown
+++ b/_events/_sample.markdown
@@ -1,14 +1,14 @@
 ---
 # put your event date and time (24 hr) here (mind the time-zone and daylight saving time!):
-eventdate: 2021-01-01 12:34:00 -0700
+eventdate: 2021-01-01 12:34:00 -0800
 # If the event last multiple day, also add the end date:
-# enddate: 2021-01-03 20:00:00 -0700
+# enddate: 2021-01-03 20:00:00 -0800
 
 # the title - this is how it will show up in listing and headings on the site:
 title: Your Event Title
 online: true
+tz: America/Los_Angeles
 # If the event is online, remove the next lines, otherwise uncomment and adjust:
-# tz: Pacific/Tahiti
 # location:
 #     city: Papeete
 #     country: French Polynesia
diff --git a/_scripts/_malformeddates.sh b/_scripts/_malformeddates.sh
index 14da02e1b6..9b6f0020ae 100755
--- a/_scripts/_malformeddates.sh
+++ b/_scripts/_malformeddates.sh
@@ -1,8 +1,8 @@
-#!/bin/bash
+#!/bin/sh
 
 malformed_event_dates=$(grep -Er --files-without-match '^eventdate: [0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2} [-+][0-9]{4}$' _events)
 if [ -n "${malformed_event_dates}" ]; then
-echo "Malformed event date in:" >&2
-echo "${malformed_event_dates}" >&2
-exit 1
+  echo "Malformed event date in:" >&2
+  echo "${malformed_event_dates}" >&2
+  exit 1
 fi
diff --git a/_scripts/_malformedevents.rb b/_scripts/_malformedevents.rb
new file mode 100755
index 0000000000..5004a9bc58
--- /dev/null
+++ b/_scripts/_malformedevents.rb
@@ -0,0 +1,67 @@
+#!/usr/bin/env ruby
+
+require 'active_support'
+require 'active_support/time'
+
+require 'yaml'
+
+issues = 0
+
+Dir['_events/*'].each do |filename|
+  data = YAML.safe_load_file(filename, permitted_classes: [Time])
+  start_date = data['eventdate']
+  end_date = data['enddate']
+  tz = data['tz']
+
+  if tz.nil?
+    message = "#{filename}: All events must have a 'tz' key"
+    if start_date
+      message += %{ (based on the time-zone offset of 'eventdate' (#{start_date}), it may be "#{ActiveSupport::TimeZone[start_date.utc_offset].tzinfo.identifier}")}
+    end
+
+    warn message
+    issues += 1
+  end
+
+  if data['online'] == false
+    if data.dig('location', 'city').nil?
+      warn "#{filename}: non-online events must have a 'location.city' key"
+      issues += 1
+    end
+
+    if data.dig('location', 'country').nil?
+      warn "#{filename}: non-online events must have a 'location.country' key"
+      issues += 1
+    end
+  end
+
+  if start_date.nil?
+    warn "#{filename}: All events must have an 'eventdate' key"
+    issues += 1
+  elsif start_date.is_a?(Time)
+    x = start_date.in_time_zone(tz)
+    if x.utc_offset != start_date.utc_offset
+      warn %{#{filename}: event 'eventdate' (#{start_date}) in not in 'tz' (#{tz}) (did you mean "#{x}"?)}
+      issues += 1
+    end
+  else
+    warn "#{filename}: event 'eventdate' (#{start_date}) is not a valid RFC822 date"
+    issues += 1
+  end
+
+  if end_date.is_a?(Time)
+    x = end_date.in_time_zone(tz)
+    if x.utc_offset != start_date.utc_offset
+      warn %{#{filename}: event 'enddate' (#{end_date}) in not in 'tz' (#{tz}) (did you mean "#{x}"?)}
+      issues += 1
+    end
+  elsif end_date
+    warn "#{filename}: event 'enddate' (#{end_date}) is not a valid RFC822 date"
+    issues += 1
+  end
+end
+
+if issues > 0
+  warn "#{issues} problems found in events."
+  exit 1
+end