diff --git a/edexOsgi/com.raytheon.uf.common.derivparam.python/utility/common_static/base/derivedParameters/functions/SliceSample.py b/edexOsgi/com.raytheon.uf.common.derivparam.python/utility/common_static/base/derivedParameters/functions/SliceSample.py
index 4c7988278b..3c42b7d19f 100644
--- a/edexOsgi/com.raytheon.uf.common.derivparam.python/utility/common_static/base/derivedParameters/functions/SliceSample.py
+++ b/edexOsgi/com.raytheon.uf.common.derivparam.python/utility/common_static/base/derivedParameters/functions/SliceSample.py
@@ -19,7 +19,9 @@
 ##
 
 import gridslice
-from numpy import zeros, float32
+from numpy import zeros, float32, NaN
+
+gridslice_maskval = 1e37
 
 def execute(*args):
     #createNumpySlice(vc, s3d, targetLevel, sense, hyb-optional)
@@ -35,9 +37,11 @@ def execute(*args):
             grid = zeros((args[0][1].shape[1], args[0][1].shape[2]),float32)
             grid.fill(args[1])
         rval = gridslice.createNumpySlice(args[0][1], args[0][0], grid, int(args[2]), int(args[3]))
+        rval[rval == gridslice_maskval] = NaN
         return rval
     else:
         # cube, cube, grid, sense, hybrid
         rval = gridslice.createNumpySlice(args[1][0], args[0][0], args[2], int(args[3]), int(args[4]))
+        rval[rval == gridslice_maskval] = NaN
         return rval
         
\ No newline at end of file