diff --git a/CHANGELOG.md b/CHANGELOG.md
index 18c2d28..1742e59 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Removed
 ### Added
 
+## [4.9.3] - 2023-05-24
+
+### Fixed
+
+- Fixed issue with tmpdir at NAS
+
 ## [4.9.2] - 2023-05-18
 
 ### Changed
diff --git a/build.csh b/build.csh
index 9bd01cf..741e9b7 100755
--- a/build.csh
+++ b/build.csh
@@ -349,7 +349,7 @@ if ( $SITE == NAS ) then
 
    # TMPDIR needs to be reset
    #-------------------------
-   if (! "$tmpdir") then
+   if ($tmpdir == '') then
       set tmpdirDFLT = "/nobackup/$USER/scratch/"
       if ($prompt) then
          echo ""
@@ -358,6 +358,8 @@ if ( $SITE == NAS ) then
          echo -n "TMPDIR [$tmpdirDFLT] "
          setenv tmpdir $<
          if ("$tmpdir" == "") setenv tmpdir $tmpdirDFLT
+      else
+         setenv tmpdir $tmpdirDFLT
       endif
    endif
    echo "TMPDIR: $tmpdir"