diff --git a/modules/deeplearning/cloud_fraction_fcn_abi.py b/modules/deeplearning/cloud_fraction_fcn_abi.py
index 6ad8a061763f503232babf103a0571feaaf10784..63bce62f7c42f11669775fc87f0b618b6bae87b3 100644
--- a/modules/deeplearning/cloud_fraction_fcn_abi.py
+++ b/modules/deeplearning/cloud_fraction_fcn_abi.py
@@ -820,7 +820,7 @@ class SRCNN:
 
         cld_frac = self.run_inference_(bt, refl, refl_lo, refl_hi, refl_std, cp)
 
-        cld_frac_out = np.zeros((y_len, x_len), dtype=np.int8)
+        cld_frac_out = np.full((y_len, x_len), -1, dtype=np.int8)
         border = int((KERNEL_SIZE - 1) / 2)
         cld_frac_out[border:y_len - border, border:x_len - border] = cld_frac[0, :, :]
 
@@ -886,7 +886,7 @@ class SRCNN:
         t1 = time.time()
         print('   inference time: ', (t1-t0))
 
-        cld_frac_out = np.zeros((y_len, x_len), dtype=np.int8)
+        cld_frac_out = np.full((y_len, x_len), -1, dtype=np.int8)
         border = int((KERNEL_SIZE - 1) / 2)
         cld_frac_out[border:h_y_len, border:x_len - border] = cld_frac_nh[0, :, :]
         cld_frac_out[h_y_len:y_len - border, border:x_len - border] = cld_frac_sh[0, :, :]