diff --git a/.env.example b/.env.example
index f3cac27e..7faf6e13 100644
--- a/.env.example
+++ b/.env.example
@@ -60,6 +60,9 @@ POLYWEATHER_EMOS_AUTO_MIN_SAMPLES=50
 POLYWEATHER_EMOS_AUTO_MAX_DELTA_CRPS=0
 POLYWEATHER_EMOS_AUTO_MAX_DELTA_MAE=0.05
 POLYWEATHER_EMOS_AUTO_MIN_DELTA_BUCKET_HIT_RATE=-0.05
+# Optional: set this to a writable runtime path if you want auto retrain to
+# promote new EMOS parameters without rebuilding the image.
+# POLYWEATHER_PROBABILITY_CALIBRATION_FILE=/var/lib/polyweather/probability_calibration/default.json
 POLYWEATHER_LGBM_ENABLED=false
 POLYWEATHER_LGBM_MODEL_PATH=/app/artifacts/models/lgbm_daily_high.txt
 POLYWEATHER_LGBM_SCHEMA_PATH=/app/artifacts/models/lgbm_daily_high_schema.json
diff --git a/docs/EMOS_TRAINING_REPORT_ZH.md b/docs/EMOS_TRAINING_REPORT_ZH.md
index 81367248..c247b91b 100644
--- a/docs/EMOS_TRAINING_REPORT_ZH.md
+++ b/docs/EMOS_TRAINING_REPORT_ZH.md
@@ -117,7 +117,13 @@ python scripts\auto_retrain_probability_calibration.py
 候选产物默认写入：
 
 ```text
-artifacts/probability_calibration/candidates/<version>/
+/var/lib/polyweather/probability_calibration/candidates/<version>/
+```
+
+最新自动训练报告默认写入：
+
+```text
+/var/lib/polyweather/probability_calibration/auto_retrain_report.json
 ```
 
 允许门禁通过后自动发布：
@@ -146,12 +152,31 @@ Docker 手动触发：
 docker compose exec -T polyweather_web python scripts/auto_retrain_probability_calibration.py
 ```
 
+查看最新报告：
+
+```text
+docker compose exec -T polyweather_web cat /var/lib/polyweather/probability_calibration/auto_retrain_report.json
+```
+
 Docker 允许门禁发布：
 
 ```text
 docker compose exec -T polyweather_web python scripts/auto_retrain_probability_calibration.py --promote-if-passed --run-tests
 ```
 
+如果希望自动发布不需要重建镜像，需要在 `.env` 中指定可写参数文件：
+
+```text
+POLYWEATHER_PROBABILITY_CALIBRATION_FILE=/var/lib/polyweather/probability_calibration/default.json
+```
+
+首次启用该路径前，先用当前镜像内置参数初始化一次：
+
+```text
+docker compose exec -T polyweather_web mkdir -p /var/lib/polyweather/probability_calibration
+docker compose exec -T polyweather_web cp /app/artifacts/probability_calibration/default.json /var/lib/polyweather/probability_calibration/default.json
+```
+
 建议后续挂到宿主机 `cron` 或 systemd timer：
 
 ```text
diff --git a/scripts/auto_retrain_probability_calibration.py b/scripts/auto_retrain_probability_calibration.py
index df273365..be8b9ebe 100644
--- a/scripts/auto_retrain_probability_calibration.py
+++ b/scripts/auto_retrain_probability_calibration.py
@@ -15,8 +15,20 @@ from src.analysis.probability_calibration import DEFAULT_CALIBRATION_FILE  # noq
 
 
 ARTIFACT_DIR = os.path.join(PROJECT_ROOT, "artifacts", "probability_calibration")
-DEFAULT_CANDIDATE_ROOT = os.path.join(ARTIFACT_DIR, "candidates")
-DEFAULT_DECISION_REPORT = os.path.join(ARTIFACT_DIR, "auto_retrain_report.json")
+
+
+def _runtime_calibration_dir() -> str:
+    runtime_dir = str(os.getenv("POLYWEATHER_RUNTIME_DATA_DIR") or "").strip()
+    if runtime_dir:
+        return os.path.join(runtime_dir, "probability_calibration")
+    return ARTIFACT_DIR
+
+
+DEFAULT_CANDIDATE_ROOT = os.path.join(_runtime_calibration_dir(), "candidates")
+DEFAULT_DECISION_REPORT = os.path.join(
+    _runtime_calibration_dir(),
+    "auto_retrain_report.json",
+)
 
 
 def _sf(value: Any) -> Optional[float]: