diff --git a/docs/notebooks/11_Climatological_ESP_forecasting.ipynb b/docs/notebooks/11_Climatological_ESP_forecasting.ipynb
index 485b8b30..c6e0f4ff 100644
--- a/docs/notebooks/11_Climatological_ESP_forecasting.ipynb
+++ b/docs/notebooks/11_Climatological_ESP_forecasting.ipynb
@@ -181,8 +181,8 @@
     "# Adjust the streamflow to convert missing data from -1.2345 format to NaN. Set all negative values to NaN.\n",
     "q_obs = q_obs.where(q_obs > 0, np.nan)\n",
     "\n",
-    "# Drop non-numerical variable\n",
-    "q_sims = q_sims.drop_vars(\"basin_fullname\")\n",
+    "# Drop non-numerical variable if present\n",
+    "q_sims = q_sims.drop_vars(\"basin_fullname\", errors=\"ignore\")\n",
     "\n",
     "# Compute the Continuous Ranked Probability Score using xskillscore\n",
     "xs.crps_ensemble(q_obs, q_sims, dim=\"time\").q_sim.values[0]"