Twenty-six New Jersey towns are ranked among the top 150 hottest real estate markets nationwide, according toRealtor.com. The highest New Jersey entry on the list was Ridgewood at 16th hottest in the nation as of April, according to Realtor.com. Ridgewood had a median listing price of $1,283,738. Nationally, parts of Columbus, Ohio, and Nashua, New Hampshire, had the top two hottest markets. Realtor.com calculates its hotness rank based on supply and demand data on its site, Sara Wiskerchen, Realtor.com’s director of corporate communications, said in an email. Realtor.com determines demand bas…