diff --git a/cave/com.raytheon.uf.viz.monitor.fog/src/com/raytheon/uf/viz/monitor/fog/FogMonitor.java b/cave/com.raytheon.uf.viz.monitor.fog/src/com/raytheon/uf/viz/monitor/fog/FogMonitor.java
index 800abef49f..3182ea5c5c 100755
--- a/cave/com.raytheon.uf.viz.monitor.fog/src/com/raytheon/uf/viz/monitor/fog/FogMonitor.java
+++ b/cave/com.raytheon.uf.viz.monitor.fog/src/com/raytheon/uf/viz/monitor/fog/FogMonitor.java
@@ -329,7 +329,9 @@ public class FogMonitor extends ObsMonitor implements IFogResourceListener {
      */
     @Override
     public void nullifyMonitor() {
-        monitor.removeMonitorListener(zoneDialog);
+        if (zoneDialog != null) {
+            monitor.removeMonitorListener(zoneDialog);
+        }
         ProductAlertObserver.removeObserver(OBS, this);
         monitor = null;
     }
@@ -380,7 +382,9 @@ public class FogMonitor extends ObsMonitor implements IFogResourceListener {
                 }
             }
         } else {
-            monitor.nullifyMonitor();
+            if (monitor != null) {
+                monitor.nullifyMonitor();
+            }
         }
     }