diff --git a/tests/test_grid_generation.py b/tests/test_grid_generation.py
index 25499542..c85be68c 100644
--- a/tests/test_grid_generation.py
+++ b/tests/test_grid_generation.py
@@ -17,7 +17,8 @@ def test_angle_between(v1, v2, v3, true_angle):
 
 
 X, Y = np.meshgrid(np.linspace(0, 90, 100), np.linspace(0, 90, 100))
-X, Y = np.meshgrid(np.linspace(0, 90, 5), np.linspace(0, 90, 5))
+# create a lat-lon mesh that covers 1/4 of the North Hemisphere
+lon, lat = np.meshgrid(np.linspace(0, 90, 5), np.linspace(0, 90, 5))
 
 
 @pytest.mark.parametrize(