In addition to showcasing a buzz-worthy performance from Kate Winslet, HBO's Mare of Easttown also introduced many viewers to the Philly accent. Philadelphia's unique way of speaking is considered one of the most unusual dialects in the U.S., but it may not be around forever. Thanks to demographic changes, the Philadelphia accent as we know it could disappear in the coming decades.
The regional dialect is characterized by distinct vowel pronunciations. In Philadelphian, Monday becomes Mondee, laugh becomes layaugh, and water becomes wooder. At least that's the case if you speak to older residents of the metro area. According to Philadelphia magazine, many hallmarks of the classic Philly accents are no longer used by Millennials.
Linguists trace this shift to Philadelphia's elite schools. Any way of speaking that falls outside the norm is viewed negatively in certain settings, so students at these schools may feel pressured to adapt the less noticeable mid-Atlantic accent. Kids at exclusive schools are also more likely to have one parent who's not from the area, so they may have a more generic way of speaking to begin with. Once that different accent is introduced into the environment, it can spread throughout the student body.
Millennial students were the first to follow this pattern a couple of decades ago, and the change is now influencing the greater Philadelphia population. If the trend continues, the classic Philly accent could become extinct within two decades. That means media highlighting the regional dialect like Mare of Easttown could one day be viewed as a linguistic time capsule. But for now, Philadelphians still know exactly what you mean when you say it's a beyoodeeful day to root for dem iggles.