diff --git a/src/traces/scattermap/hover.js b/src/traces/scattermap/hover.js
index af476fd6778..2652219d1df 100644
--- a/src/traces/scattermap/hover.js
+++ b/src/traces/scattermap/hover.js
@@ -29,6 +29,7 @@ function hoverPoints(pointData, xval, yval) {
 
     // shift longitude to [-180, 180] to determine closest point
     var lonShift = winding * 360;
+    if(isNaN(lonShift)) lonShift = 0;
     var xval2 = xval - lonShift;
 
     function distFn(d) {