diff --git a/test/dotcom/system_status/subway_test.exs b/test/dotcom/system_status/subway_test.exs
index b22e09d053..1ff65f65a3 100644
--- a/test/dotcom/system_status/subway_test.exs
+++ b/test/dotcom/system_status/subway_test.exs
@@ -3,7 +3,7 @@ defmodule Dotcom.SystemStatus.SubwayTest do
   doctest Dotcom.SystemStatus.Subway
 
   alias Dotcom.SystemStatus.Subway
-  alias Test.Support.Factories.Alerts.Alert
+  import Test.Support.Factories.Alerts.Alert
   alias Test.Support.Factories.Alerts.InformedEntity
   alias Test.Support.Factories.Alerts.InformedEntitySet
 
@@ -33,7 +33,10 @@ defmodule Dotcom.SystemStatus.SubwayTest do
       affected_route_id = Faker.Util.pick(@lines_without_branches)
       time = time_today()
       effect = Faker.Util.pick(@effects)
-      alerts = [current_alert(route_id: affected_route_id, time: time, effect: effect)]
+
+      alerts = [
+        build(:alert, effect: effect) |> active_during(time) |> for_route(affected_route_id)
+      ]
 
       # Exercise
       groups = Subway.subway_status(alerts, time)
@@ -565,7 +568,7 @@ defmodule Dotcom.SystemStatus.SubwayTest do
     effect = opts[:effect] || Faker.Util.pick(@effects)
     active_period = opts |> Keyword.fetch!(:active_period)
 
-    Alert.build(:alert,
+    build(:alert,
       effect: effect,
       informed_entity:
         InformedEntitySet.build(:informed_entity_set,
diff --git a/test/support/factories/alerts/alert.ex b/test/support/factories/alerts/alert.ex
index 4fc24f3760..ba9af4e453 100644
--- a/test/support/factories/alerts/alert.ex
+++ b/test/support/factories/alerts/alert.ex
@@ -6,8 +6,11 @@ defmodule Test.Support.Factories.Alerts.Alert do
   use ExMachina
 
   alias Alerts.{Alert, Priority}
+  alias Test.Support.Factories.Alerts.InformedEntity
   alias Test.Support.Factories.Alerts.InformedEntitySet
 
+  @high_priority_effects [:delay, :shuttle, :station_closure, :suspension]
+
   def alert_factory do
     %Alert{
       id: :rand.uniform(999) |> Integer.to_string(),
@@ -28,4 +31,40 @@ defmodule Test.Support.Factories.Alerts.Alert do
       url: Faker.Internet.url()
     }
   end
+
+  def for_route(alert, route_id) do
+    %{
+      alert
+      | informed_entity:
+          InformedEntitySet.build(:informed_entity_set,
+            route: route_id,
+            entities: [
+              InformedEntity.build(:informed_entity, route: route_id)
+            ]
+          )
+    }
+  end
+
+  def with_high_priority_effect(alert) do
+    %{alert | effect: Faker.Util.pick(@high_priority_effects)}
+  end
+
+  def active_during(alert, time) do
+    %{alert | active_period: [{time_before(time), time_after(time)}]}
+  end
+
+  # Returns a random time during the day today before the time provided.
+  defp time_before(time) do
+    between(Timex.beginning_of_day(time), time)
+  end
+
+  # Returns a random time during the day today after the time provided.
+  defp time_after(time) do
+    between(time, Timex.end_of_day(time))
+  end
+
+  # Returns a random time between the times provided in the Eastern time zone.
+  defp between(time1, time2) do
+    Faker.DateTime.between(time1, time2) |> Timex.to_datetime("America/New_York")
+  end
 end