diff --git a/kort7/app.js b/kort7/app.js
index 05f7ff0..23ee16b 100644
--- a/kort7/app.js
+++ b/kort7/app.js
@@ -122,6 +122,19 @@ function distanceToBoundsMeters(lat, lon, bounds) {
   return metersBetween(lat, lon, clampedLat, clampedLon);
 }
 
+function maxDistanceToBoundsCornerMeters(lat, lon, bounds) {
+  const corners = [
+    [bounds.getSouth(), bounds.getWest()],
+    [bounds.getSouth(), bounds.getEast()],
+    [bounds.getNorth(), bounds.getWest()],
+    [bounds.getNorth(), bounds.getEast()]
+  ];
+
+  return Math.max(...corners.map(([cornerLat, cornerLon]) =>
+    metersBetween(lat, lon, cornerLat, cornerLon)
+  ));
+}
+
 function getPresenceState(lat, lon, uncertaintyM) {
   const bounds = map.getBounds();
   const centerInside = bounds.contains([lat, lon]);
@@ -136,6 +149,14 @@ function getPresenceState(lat, lon, uncertaintyM) {
   if (uncertaintyM > 0) {
     const distToBounds = distanceToBoundsMeters(lat, lon, bounds);
     if (distToBounds <= uncertaintyM) {
+      const maxCornerDistance = maxDistanceToBoundsCornerMeters(lat, lon, bounds);
+      if (uncertaintyM >= maxCornerDistance) {
+        return {
+          code: "covers",
+          label: "dækker hele kortet"
+        };
+      }
+
       return {
         code: "possible",
         label: "muligvis"
@@ -191,6 +212,8 @@ function syncUncertaintyCircle(v) {
 
   if (v.presenceState === "inside") {
     v.uncertaintyCircle.setStyle({ opacity: 0.7, fillOpacity: 0.08 });
+  } else if (v.presenceState === "covers") {
+    v.uncertaintyCircle.setStyle({ opacity: 0.28, fillOpacity: 0.05 });
   } else if (v.presenceState === "possible") {
     v.uncertaintyCircle.setStyle({ opacity: 0.35, fillOpacity: 0.03 });
   } else {
@@ -358,7 +381,7 @@ function updateVehicleDisplay(v) {
     if (map.hasLayer(v.marker)) {
       map.removeLayer(v.marker);
     }
-    v.trail.setStyle({ opacity: 0.25 });
+    v.trail.setStyle({ opacity: presence.code === "covers" ? 0.4 : 0.25 });
   }
 
   v.marker.setPopupContent(popupHtml(v.name, v));
@@ -367,21 +390,32 @@ function updateVehicleDisplay(v) {
 }
 
 function updateAlerts() {
-  const possibleVehicles = vehicleNames
+  const alertVehicles = vehicleNames
     .map(name => vehicles[name])
-    .filter(v => v.presenceState === "possible");
+    .filter(v => v.presenceState === "possible" || v.presenceState === "covers");
 
-  if (possibleVehicles.length === 0) {
+  if (alertVehicles.length === 0) {
     alertsEl.innerHTML = "";
     return;
   }
 
-  alertsEl.innerHTML = possibleVehicles.map(v => `
-    <div class="alert-item">
-      <strong>${v.name}: mulig tilstedeværelse</strong>
-      Estimatet er udenfor kortet, men usikkerheden overlapper det viste område.
-    </div>
-  `).join("");
+  alertsEl.innerHTML = alertVehicles.map(v => {
+    if (v.presenceState === "covers") {
+      return `
+        <div class="alert-item">
+          <strong>${v.name}: usikkerhed dækker hele kortet</strong>
+          Estimatet er udenfor kortet, men usikkerheden spænder over hele viewporten.
+        </div>
+      `;
+    }
+
+    return `
+      <div class="alert-item">
+        <strong>${v.name}: mulig tilstedeværelse</strong>
+        Estimatet er udenfor kortet, men usikkerheden overlapper det viste område delvist.
+      </div>
+    `;
+  }).join("");
 }
 
 function updateStatus() {