diff --git a/src/gsi/setuprad.f90 b/src/gsi/setuprad.f90
index 7f001ea9c..a5b2a6b28 100644
--- a/src/gsi/setuprad.f90
+++ b/src/gsi/setuprad.f90
@@ -2108,7 +2108,7 @@ subroutine setuprad(obsLL,odiagLL,lunin,mype,aivals,stats,nchanl,nreal,nobs,&
   deallocate(diagbufchan)
   deallocate(sc_index)
 
-  if (rad_diagsave) then
+  if (rad_diagsave .and. nchanl_diag > 0) then
      if (netcdf_diag) call nc_diag_write
      if(binary_diag) call final_binary_diag_
      if (lextra .and. allocated(diagbufex)) deallocate(diagbufex)