diff --git a/src/MNH/phys_paramn.f90 b/src/MNH/phys_paramn.f90
index ae0b2f7f3696e1494096d5b4a317eb3647aa179c..099b38670b0b1904f419041e5244e67671f80eb1 100644
--- a/src/MNH/phys_paramn.f90
+++ b/src/MNH/phys_paramn.f90
@@ -235,6 +235,7 @@ END MODULE MODI_PHYS_PARAM_n
 !  P. Wautelet 28/03/2019: use MNHTIME for time measurement variables
 !  P. Wautelet 26/04/2019: replace non-standard FLOAT function by REAL function
 !  P. Wautelet 20/05/2019: add name argument to ADDnFIELD_ll + new ADD4DFIELD_ll subroutine
+!  P. Wautelet 21/11/2019: ZRG_HOUR and ZRAT_HOUR are now parameter arrays
 !!-------------------------------------------------------------------------------
 !
 !*       0.     DECLARATIONS
@@ -380,20 +381,19 @@ REAL, DIMENSION(:,:,:,:), ALLOCATABLE  :: ZSVT
 REAL, DIMENSION(:,:,:), ALLOCATABLE :: ZEXN   ! Atmospheric density and Exner
 REAL, DIMENSION(:,:,:), ALLOCATABLE :: ZSIGMF   ! MF contribution to XSIGS
 !
-REAL, DIMENSION(0:24) :: ZRG_HOUR =  (/ 0., 0., 0., 0., 0., 32.04, 114.19,  &
-                                      228.01, 351.25, 465.49, 557.24,       &
-                                      616.82, 638.33, 619.43, 566.56,       &
-                                      474.71, 359.20, 230.87, 115.72,       &
-                                      32.48, 0., 0., 0., 0., 0. /)
-!
-REAL, DIMENSION(0:24) :: ZRAT_HOUR = (/ 326.00, 325.93, 325.12, 324.41,     &
-                                      323.16, 321.95, 322.51, 325.16,       &
-                                      328.01, 331.46, 335.58, 340.00,       &
-                                      345.20, 350.32, 354.20, 356.58,       &
-                                      356.56, 355.33, 352.79, 351.34,       &
-                                      347.00, 342.00, 337.00, 332.00,       &
-                                      326.00     /)
-!
+REAL, DIMENSION(0:24), parameter :: ZRG_HOUR =  (/ 0., 0., 0., 0., 0., 32.04, 114.19, &
+                                                   228.01, 351.25, 465.49, 557.24,    &
+                                                   616.82, 638.33, 619.43, 566.56,    &
+                                                   474.71, 359.20, 230.87, 115.72,    &
+                                                   32.48, 0., 0., 0., 0., 0. /)
+!
+REAL, DIMENSION(0:24), parameter :: ZRAT_HOUR = (/ 326.00, 325.93, 325.12, 324.41, &
+                                                   323.16, 321.95, 322.51, 325.16, &
+                                                   328.01, 331.46, 335.58, 340.00, &
+                                                   345.20, 350.32, 354.20, 356.58, &
+                                                   356.56, 355.33, 352.79, 351.34, &
+                                                   347.00, 342.00, 337.00, 332.00, &
+                                                   326.00     /)
 !
 character(len=6) :: ynum
 INTEGER  :: IHOUR               ! parameters necessary for the temporal