diff --git a/modules/util/abi_surfrad.py b/modules/util/abi_surfrad.py
index 4b4427bb2cba7f63a0b0a78e0af8f8adb4f81a00..6c2037125c1c54c18544f8bc9ddf48dd0351b1cd 100644
--- a/modules/util/abi_surfrad.py
+++ b/modules/util/abi_surfrad.py
@@ -88,10 +88,10 @@ def get_cloud_frac_5cat(grd_k):
     grd_k = np.where(np.isnan(grd_k), 0, grd_k)
     grd_k = np.where(grd_k < 0.5, 0, 1)
 
-    s = grd_k[:, 0::4, 0::4] + grd_k[:, 1::4, 0::4] + grd_k[:, 2::4, 0::4] + grd_k[:, 3::4, 0::4] + \
-        grd_k[:, 0::4, 1::4] + grd_k[:, 1::4, 1::4] + grd_k[:, 2::4, 1::4] + grd_k[:, 3::4, 1::4] + \
-        grd_k[:, 0::4, 2::4] + grd_k[:, 1::4, 2::4] + grd_k[:, 2::4, 2::4] + grd_k[:, 3::4, 2::4] + \
-        grd_k[:, 0::4, 3::4] + grd_k[:, 1::4, 3::4] + grd_k[:, 2::4, 3::4] + grd_k[:, 3::4, 3::4]
+    s = grd_k[0::4, 0::4] + grd_k[1::4, 0::4] + grd_k[2::4, 0::4] + grd_k[3::4, 0::4] + \
+        grd_k[0::4, 1::4] + grd_k[1::4, 1::4] + grd_k[2::4, 1::4] + grd_k[3::4, 1::4] + \
+        grd_k[0::4, 2::4] + grd_k[1::4, 2::4] + grd_k[2::4, 2::4] + grd_k[3::4, 2::4] + \
+        grd_k[0::4, 3::4] + grd_k[1::4, 3::4] + grd_k[2::4, 3::4] + grd_k[3::4, 3::4]
 
     cat_0 = np.logical_and(s >= 0, s < 1)
     cat_1 = np.logical_and(s >= 1, s < 6)