diff --git a/physics/module_sf_mynn.F90 b/physics/module_sf_mynn.F90
index 98e894155..0d81e145a 100644
--- a/physics/module_sf_mynn.F90
+++ b/physics/module_sf_mynn.F90
@@ -848,7 +848,7 @@ SUBROUTINE SFCLAY1D_mynn(flag_iter,                            &
 
       DO I=its,ite
          ! CONVERT LOWEST LAYER TEMPERATURE TO POTENTIAL TEMPERATURE:     
-         TH1D(I)=T1D(I)**(100000./P1D(I))**ROVCP !(Theta, K)
+         TH1D(I)=T1D(I)*(100000./P1D(I))**ROVCP  !(Theta, K)
          TC1D(I)=T1D(I)-273.15                   !(T, Celsius)
       ENDDO