diff --git a/cmd/ingestd/web/app.js b/cmd/ingestd/web/app.js
index 2de0997..2e3b55b 100644
--- a/cmd/ingestd/web/app.js
+++ b/cmd/ingestd/web/app.js
@@ -409,6 +409,26 @@ function computeRainProbability(latest, pressureTrend1h) {
   return { prob, label };
 }
 
+function extendForecastTo(points, endTime) {
+  if (!points || !points.length || !endTime) {
+    return points;
+  }
+  const last = points[points.length - 1];
+  const lastTs = new Date(last.ts).getTime();
+  if (Number.isNaN(lastTs)) {
+    return points;
+  }
+  const endTs = endTime.getTime();
+  if (endTs <= lastTs) {
+    return points;
+  }
+  const maxGapMs = 75 * 60 * 1000;
+  if (endTs-lastTs > maxGapMs) {
+    return points;
+  }
+  return [...points, { ...last, ts: new Date(endTs).toISOString() }];
+}
+
 function updateSiteMeta(site, model, tzLabel) {
   const home = document.getElementById("site-home");
   const suffix = document.getElementById("site-meta-suffix");
@@ -520,6 +540,7 @@ function renderDashboard(data) {
 
   const obsFiltered = filterRange(obs, rangeStart, rangeEnd);
   const forecast = filterRange(forecastAll, rangeStart, rangeEnd);
+  const forecastLine = extendForecastTo(forecast, rangeEnd);
   const lastPressureTrend = lastNonNull(obsFiltered, "pressure_trend_1h");
   const rainProb = computeRainProbability(latest, lastPressureTrend);
   if (rainProb) {
@@ -581,7 +602,7 @@ function renderDashboard(data) {
     data: {
       datasets: [
         { label: "obs temp C", data: series(obsFiltered, "temp_c"), borderColor: colors.obs },
-        { label: "forecast temp C", data: series(forecast, "temp_c"), borderColor: colors.forecast },
+        { label: "forecast temp C", data: series(forecastLine, "temp_c"), borderColor: colors.forecast },
       ],
     },
     options: baseOptions(range),
@@ -594,8 +615,8 @@ function renderDashboard(data) {
       datasets: [
         { label: "obs wind m/s", data: series(obsFiltered, "wind_m_s"), borderColor: colors.obs },
         { label: "obs gust m/s", data: series(obsFiltered, "wind_gust_m_s"), borderColor: colors.gust },
-        { label: "forecast wind m/s", data: series(forecast, "wind_m_s"), borderColor: colors.forecast },
-        { label: "forecast gust m/s", data: series(forecast, "wind_gust_m_s"), borderColor: "#f7d79f" },
+        { label: "forecast wind m/s", data: series(forecastLine, "wind_m_s"), borderColor: colors.forecast },
+        { label: "forecast gust m/s", data: series(forecastLine, "wind_gust_m_s"), borderColor: "#f7d79f" },
       ],
     },
     options: baseOptions(range),
@@ -607,7 +628,7 @@ function renderDashboard(data) {
     data: {
       datasets: [
         { label: "obs humidity %", data: series(obsFiltered, "rh"), borderColor: colors.humidity },
-        { label: "forecast rh %", data: series(forecast, "rh"), borderColor: colors.forecast },
+        { label: "forecast rh %", data: series(forecastLine, "rh"), borderColor: colors.forecast },
       ],
     },
     options: baseOptions(range),
@@ -619,7 +640,7 @@ function renderDashboard(data) {
     data: {
       datasets: [
         { label: "obs pressure hPa", data: series(obsFiltered, "pressure_hpa"), borderColor: colors.pressure },
-        { label: "forecast msl hPa", data: series(forecast, "pressure_msl_hpa"), borderColor: colors.forecast },
+        { label: "forecast msl hPa", data: series(forecastLine, "pressure_msl_hpa"), borderColor: colors.forecast },
       ],
     },
     options: baseOptions(range),