The script is operating properly on your site. With the default 200 mile distance from your lat/long, there are no earthquakes in that radius, so no map is displayed.
If you use
http://southcoastwx.net/wxquake.php?distance=2000 for a 2000 mile radius, you'll see a map, and the nearest earthquake to you is
19 mi SSW of Wellsboro, Pennsylvania 2.6
333 mi Thu, 05-Apr-2018 6:19pm EDT
You can adjust the distance filter and the map scaling in the wxquake.php page
$setDistanceRadius = 200; // same units as first unit in $setDistanceDisplay
# NOTE: quakes of magnitude 1.0+ are available for USA locations only.
# non-USA location earthquakes of magnitude 4.0+ are the only ones available from the USGS
$setMinMagnitude = '2.0'; // minimum Richter Magnitude to display
$setHighMagnitude = '4.0'; // highlight this Magnitude and greater
$setMapZoomDefault = 7; // default zoom for Google Map 1=world to 13=street
I'd suggest you use
$setDistanceRadius = 1500; // same units as first unit in $setDistanceDisplay
# NOTE: quakes of magnitude 1.0+ are available for USA locations only.
# non-USA location earthquakes of magnitude 4.0+ are the only ones available from the USGS
$setMinMagnitude = '2.0'; // minimum Richter Magnitude to display
$setHighMagnitude = '4.0'; // highlight this Magnitude and greater
$setMapZoomDefault = 5; // default zoom for Google Map 1=world to 13=street
and it will show quakes on your map.