diff --git a/env/HERA.env b/env/HERA.env
index 09743967b55..80cd7cddaff 100755
--- a/env/HERA.env
+++ b/env/HERA.env
@@ -9,7 +9,7 @@ fi
 
 step=$1
 
-export launcher="srun -l --export=ALL"
+export launcher="srun -l --export=ALL --hint=nomultithread"
 export mpmd_opt="--multi-prog --output=mpmd.%j.%t.out"
 
 #export POSTAMBLE_CMD='report-mem'
@@ -50,7 +50,7 @@ if [[ "${step}" = "prep" ]] || [[ "${step}" = "prepbufr" ]]; then
     export POE="NO"
     export BACK="NO"
     export sys_tp="HERA"
-    export launcher_PREP="srun"
+    export launcher_PREP="srun --hint=nomultithread"
 
 elif [[ "${step}" = "prepsnowobs" ]]; then
 
diff --git a/env/HERCULES.env b/env/HERCULES.env
index 9ec112c6992..bed1d112811 100755
--- a/env/HERCULES.env
+++ b/env/HERCULES.env
@@ -9,7 +9,7 @@ fi
 
 step=$1
 
-export launcher="srun -l --export=ALL"
+export launcher="srun -l --export=ALL --hint=nomultithread"
 export mpmd_opt="--multi-prog --output=mpmd.%j.%t.out"
 
 # Configure MPI environment
@@ -48,7 +48,7 @@ case ${step} in
     export POE="NO"
     export BACK=${BACK:-"YES"}
     export sys_tp="HERCULES"
-    export launcher_PREP="srun"
+    export launcher_PREP="srun --hint=nomultithread"
  ;;
  "prepsnowobs")
 
diff --git a/env/ORION.env b/env/ORION.env
index 3b8053d060f..45fd607aa5f 100755
--- a/env/ORION.env
+++ b/env/ORION.env
@@ -9,7 +9,7 @@ fi
 
 step=$1
 
-export launcher="srun -l --export=ALL"
+export launcher="srun -l --export=ALL --hint=nomultithread"
 export mpmd_opt="--multi-prog --output=mpmd.%j.%t.out"
 
 # Configure MPI environment
@@ -45,7 +45,7 @@ if [[ "${step}" = "prep" ]] || [[ "${step}" = "prepbufr" ]]; then
     export POE="NO"
     export BACK=${BACK:-"YES"}
     export sys_tp="ORION"
-    export launcher_PREP="srun"
+    export launcher_PREP="srun --hint=nomultithread"
 
 elif [[ "${step}" = "prepsnowobs" ]]; then