In the "Settings.php" around line 176, look for this.
$SITE['NWSforecasts'] = array( // for the advforecast2.php V3.xx version script
// use "Zone|Location|Point-printableURL", as entries .. first one will be the default forecast.
"kyz074|Barren County, Kentucky|http://forecast.weather.gov/MapClick.php?CityName=Glasgow&state=KY&site=LMK&textField1=36.9991&textField2=-85.9215&e=0&TextType=2",
"kyz077|Adair County, Kentucky|http://forecast.weather.gov/MapClick.php?CityName=Columbia&state=KY&site=LMK&textField1=37.098&textField2=-85.3081&e=0&TextType=2",
);
Just add your county codes and forecast URL. I have 17 different counties, but shortened it to save space here.