Fix WU historical current observation merge

frontend/components/dashboard/scan-terminal/LiveTemperatureThresholdChart.tsx

@@ -89,6 +89,10 @@ function formatCityLocalDate(tzOffsetSeconds: number | null | undefined) {
   return `${y}-${m}-${d}`;
 }
 
+function getWundergroundDailyHigh(hourly: HourlyForecast) {
+  return validNumber(hourly?.wundergroundCurrent?.max_so_far) ?? null;
+}
+
 // ── Main component ─────────────────────────────────────────────────────
 
 export function LiveTemperatureThresholdChart({
@@ -490,7 +494,7 @@ export function LiveTemperatureThresholdChart({
     [row, chartHourly, settlementPlate],
   );
   const displayRunwayTemp = selectDisplayRunwayTemp(liveTemp, currentRunwayTemp, hasRunwayData);
-  const wundergroundDailyHigh = validNumber(chartHourly?.airportCurrent?.max_so_far ?? chartHourly?.airportPrimary?.max_so_far) ?? null;
+  const wundergroundDailyHigh = getWundergroundDailyHigh(chartHourly);
 
   const localDateStr = chartLocalDate || new Date().toISOString().slice(0, 10);
   const modelSources = (row?.model_cluster_sources && Object.keys(row.model_cluster_sources).length > 0)
@@ -795,6 +799,7 @@ export const __getDebPeakWindowRangeForTest = getDebPeakWindowRange;
 export const __getLiveObservationLabelsForTest = getLiveObservationLabels;
 export const __getObservationDisplayMetricsForTest = getObservationDisplayMetrics;
 export const __getPeakGlowStateForTest = getPeakGlowState;
+export const __getWundergroundDailyHighForTest = getWundergroundDailyHigh;
 export const __shouldPollLiveChartForTest = shouldPollLiveChart;
 export const __mergePatchIntoHourlyForTest = mergePatchIntoHourly;
 export const __selectDisplayRunwayTempForTest = selectDisplayRunwayTemp;

frontend/components/dashboard/scan-terminal/__tests__/temperatureDefaultVisibilityPolicy.test.ts

@@ -5,6 +5,7 @@ import {
   __getLiveObservationLabelsForTest,
   __getObservationDisplayMetricsForTest,
   __getPeakGlowStateForTest,
+  __getWundergroundDailyHighForTest,
   __getVisibleTemperatureSeriesForTest,
   __isTemperatureSeriesVisibleByDefaultForTest,
   __mergePatchIntoHourlyForTest,
@@ -102,6 +103,22 @@ export function runTests() {
     "morning observations near the intraday observed high should not trigger peak glow before the forecast hot window",
   );
 
+  assert(
+    __getWundergroundDailyHighForTest({
+      wundergroundCurrent: { max_so_far: 26 },
+      airportCurrent: { max_so_far: 27 },
+      airportPrimary: { max_so_far: 27 },
+    } as any) === 26,
+    "WU display should use Wunderground historical.json high before airport/METAR highs",
+  );
+  assert(
+    __getWundergroundDailyHighForTest({
+      airportCurrent: { max_so_far: 27 },
+      airportPrimary: { max_so_far: 27 },
+    } as any) === null,
+    "WU display should not fall back to airport/METAR highs when historical.json is missing",
+  );
+
   const guangzhou = {
     city: "guangzhou",
     local_date: "2026-05-25",

frontend/components/dashboard/scan-terminal/temperature-chart-logic.ts

@@ -784,6 +784,7 @@ type HourlyForecast = {
   amos?: AmosData | null;
   airportCurrent?: AirportCurrentConditions | null;
   airportPrimary?: AirportCurrentConditions | null;
+  wundergroundCurrent?: AirportCurrentConditions | null;
   forecastDaily?: ForecastDay[];
   multiModelDaily?: Record<string, DailyModelForecast>;
   probabilities?: LegacyGaussianProbabilitySource | null;
@@ -809,6 +810,7 @@ function seedHourlyForecastFromRow(row: ScanOpportunityRow | null): HourlyForeca
     amos: null,
     airportCurrent: null,
     airportPrimary: null,
+    wundergroundCurrent: (row as any)?.wunderground_current || null,
     forecastDaily: [],
     multiModelDaily: {},
     probabilities: {
@@ -844,6 +846,7 @@ function parseHourlyForecastFromCityDetail(json: CityDetail | null): HourlyForec
     amos: json.amos || null,
     airportCurrent: json.airport_current || null,
     airportPrimary: json.airport_primary || null,
+    wundergroundCurrent: (json as any).wunderground_current || (json as any)?.official?.wunderground_current || null,
     forecastDaily: json.forecast?.daily || [],
     multiModelDaily: json.multi_model_daily || {},
     probabilities: json.probabilities || null,