diff --git a/contrib/cmake/cmake/compiler_warnings.cmake b/contrib/cmake/cmake/compiler_warnings.cmake
index c214e4464..e49e43947 100644
--- a/contrib/cmake/cmake/compiler_warnings.cmake
+++ b/contrib/cmake/cmake/compiler_warnings.cmake
@@ -15,6 +15,13 @@ elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
   # FIXME: Remove "x.." when CMP0054 is set to NEW
 elseif ("x${CMAKE_CXX_COMPILER_ID}" STREQUAL "xMSVC")
   list(APPEND WARNING_FLAGS_TO_CHECK ${MSVC_WARNINGS})
+
+  # CMake's default flags include /W3 already so remove them if
+  # they already exist.
+  if ("${CMAKE_CXX_FLAGS}" MATCHES "/W3")
+    string(REPLACE "/W3" "" _cmake_cxx_flags_remove_w3 "${CMAKE_CXX_FLAGS}")
+    set(CMAKE_CXX_FLAGS "${_cmake_cxx_flags_remove_w3}" CACHE STRING "" FORCE)
+  endif()
 else()
   message(AUTHOR_WARNING "Unknown compiler")
 endif()