diff --git a/CHANGELOG.md b/CHANGELOG.md
index f28461a14d5f..a7f4832ad22c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -31,6 +31,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Updated `components.yaml`. These changes are to support using Spack to build MAPL
   - ESMA_cmake v3.10.0 (add `FindESMF.cmake` from NOAA-EMC)
   - ecbuild geos/v1.2.0 (updat `FindNetCDF.cmake` to that from NOAA-EMC)
+- File not found error handling in ExtData improved for non-templated filenames
 
 ### Removed
 
diff --git a/gridcomps/ExtData/ExtDataGridCompMod.F90 b/gridcomps/ExtData/ExtDataGridCompMod.F90
index c728b2e77cbc..4401507c0604 100644
--- a/gridcomps/ExtData/ExtDataGridCompMod.F90
+++ b/gridcomps/ExtData/ExtDataGridCompMod.F90
@@ -2113,8 +2113,10 @@ subroutine GetLevs(item, time, state, allowExtrap, rc)
         if (found) then
            call MakeMetadata(file,item%pfioCollection_id,metadata,__RC__)
         else
-           if (allowExtrap .and. (item%cyclic == 'n') ) then
+           if (index(item%file,'%') == 0) then
+              _ASSERT(.false.,'File ' // trim(item%file) // ' not found')
 
+           else if (allowExtrap .and. (item%cyclic == 'n') ) then
               ftime = item%reff_time
               n = 0
               maxOffSet = 100