diff --git a/api/app/weather_models/precip_rdps_model.py b/api/app/weather_models/precip_rdps_model.py
index 866387004..5e9f7ebd5 100644
--- a/api/app/weather_models/precip_rdps_model.py
+++ b/api/app/weather_models/precip_rdps_model.py
@@ -91,9 +91,9 @@ async def generate_24_hour_accumulating_precip_raster(timestamp: datetime):
     """
     (yesterday_key, today_key) = get_raster_keys_to_diff(timestamp)
     (day_data, day_geotransform, day_projection) = await read_into_memory(today_key)
+    if day_data is None:
+        raise ValueError("No precip raster data for today_key: %s" % today_key)
     if yesterday_key is None:
-        if day_data is None:
-            raise ValueError("No precip raster data for %s" % today_key)
         return (day_data, day_geotransform, day_projection)
 
     yesterday_time = timestamp - timedelta(days=1)