diff --git a/tests/test_model.py b/tests/test_model.py
index feafc91..43322c7 100644
--- a/tests/test_model.py
+++ b/tests/test_model.py
@@ -86,7 +86,7 @@ def assert_approx_equality(v_out, v_ref) -> None:
         err = np.abs(v_out - v_ref).mean()
         mag = np.abs(v_ref).mean()
         print(err / mag)
-        assert err / mag <= 1e-4
+        assert err / mag <= 1e-3
 
     # Check the outputs.
     for k in pred.surf_vars: