diff --git a/lib/microwaveprop/workers/propagation_grid_worker.ex b/lib/microwaveprop/workers/propagation_grid_worker.ex
index 5c182055..e7833c17 100644
--- a/lib/microwaveprop/workers/propagation_grid_worker.ex
+++ b/lib/microwaveprop/workers/propagation_grid_worker.ex
@@ -17,7 +17,9 @@ defmodule Microwaveprop.Workers.PropagationGridWorker do
 
   @impl Oban.Worker
   def perform(%Oban.Job{}) do
-    valid_time = HrrrClient.nearest_hrrr_hour(DateTime.utc_now())
+    # HRRR takes ~45min to publish after the hour. Use 2 hours ago to ensure availability.
+    two_hours_ago = DateTime.add(DateTime.utc_now(), -2, :hour)
+    valid_time = HrrrClient.nearest_hrrr_hour(two_hours_ago)
     points = Grid.conus_points()
 
     Logger.info("PropagationGrid: fetching HRRR for #{valid_time}, #{length(points)} points")