diff --git a/modules/default/weatherforecast/weatherforecast.js b/modules/default/weatherforecast/weatherforecast.js
index f54467e5..0168e559 100644
--- a/modules/default/weatherforecast/weatherforecast.js
+++ b/modules/default/weatherforecast/weatherforecast.js
@@ -142,10 +142,10 @@ Module.register("weatherforecast",{
 
 			var maxTempCell = document.createElement("td");
 			maxTempCell.innerHTML = forecast.maxTemp;
-			if(this.config.scale.toUpperCase() == "C") {
+			if(typeof(this.config.scale) == "string" && this.config.scale.toUpperCase() == "C") {
 				maxTempCell.innerHTML += " °C";
 			} else {
-				if(this.config.scale.toUpperCase() == "F") {
+				if(typeof(this.config.scale) == "string" && this.config.scale.toUpperCase() == "F") {
 					maxTempCell.innerHTML += " °F";
 				}
 			}
@@ -154,10 +154,10 @@ Module.register("weatherforecast",{
 
 			var minTempCell = document.createElement("td");
 			minTempCell.innerHTML = forecast.minTemp;
-			if(this.config.scale.toUpperCase() == "C") {
+			if(typeof(this.config.scale) == "string" && this.config.scale.toUpperCase() == "C") {
 				minTempCell.innerHTML += " °C";
 			} else {
-				if(this.config.scale.toUpperCase() == "F") {
+				if(typeof(this.config.scale) == "string" && this.config.scale.toUpperCase() == "F") {
 					minTempCell.innerHTML += " °F";
 				}
 			}