diff --git a/frontend/components/dashboard/scan-terminal/__tests__/temperatureDefaultVisibilityPolicy.test.ts b/frontend/components/dashboard/scan-terminal/__tests__/temperatureDefaultVisibilityPolicy.test.ts
index ff4837f5..52c2ac0e 100644
--- a/frontend/components/dashboard/scan-terminal/__tests__/temperatureDefaultVisibilityPolicy.test.ts
+++ b/frontend/components/dashboard/scan-terminal/__tests__/temperatureDefaultVisibilityPolicy.test.ts
@@ -226,8 +226,45 @@ export function runTests() {
     "Shenzhen HKO observations should remain visible by default",
   );
   assert(
-    !__isTemperatureSeriesVisibleByDefaultForTest("new york", "madis"),
-    "non-Hong Kong/Shenzhen airport-primary observations should be hidden by default",
+    __isTemperatureSeriesVisibleByDefaultForTest("new york", "madis"),
+    "airport-primary weather-station observations should be visible by default",
+  );
+
+  const amsterdamKnmi = __buildTemperatureChartDataForTest(
+    {
+      city: "amsterdam",
+      local_date: "2026-05-29",
+      local_time: "17:03",
+      tz_offset_seconds: 2 * 60 * 60,
+      airport: "EHAM",
+    } as any,
+    {
+      localTime: "17:03",
+      times: ["00:00", "06:00", "12:00", "18:00"],
+      temps: [19, 18, 27, 20],
+      airportPrimary: {
+        source_code: "knmi",
+        source_label: "KNMI",
+        temp: 19.0,
+        obs_time: "2026-05-29T15:03:00Z",
+      },
+      airportPrimaryTodayObs: [
+        { time: "2026-05-29T13:00:00Z", temp: 26.2 },
+        { time: "2026-05-29T14:00:00Z", temp: 24.5 },
+        { time: "2026-05-29T15:00:00Z", temp: 19.9 },
+      ],
+    } as any,
+    "1D",
+  );
+  const amsterdamDefaultSeries = __getActiveTemperatureSeriesForTest(
+    "amsterdam",
+    amsterdamKnmi.series as any,
+    {},
+    true,
+  );
+  assert(
+    amsterdamDefaultSeries.some((item: any) => item.key === "madis" && item.label === "KNMI"),
+    "Amsterdam KNMI weather-station curve should be visible by default",
   );
 
   const ankaraMgmWithMetarBackup = __buildTemperatureChartDataForTest(
diff --git a/frontend/components/dashboard/scan-terminal/temperature-chart-logic.ts b/frontend/components/dashboard/scan-terminal/temperature-chart-logic.ts
index 23d88075..92489bf6 100644
--- a/frontend/components/dashboard/scan-terminal/temperature-chart-logic.ts
+++ b/frontend/components/dashboard/scan-terminal/temperature-chart-logic.ts
@@ -95,14 +95,7 @@ function isTemperatureSeriesVisibleByDefault(city: string, seriesKey: string) {
     );
   }
   if (seriesKey === "madis") {
-    const cityKey = normalizeCityKey(city);
-    return (
-      cityKey === "hongkong" ||
-      cityKey === "laufaushan" ||
-      cityKey === "shenzhen" ||
-      cityKey === "ankara" ||
-      cityKey === "istanbul"
-    );
+    return true;
   }
   return true;
 }