To assess the possibility of regiolect formation, we evaluated the pronunciation similarity between Frisian, Town Frisian, and Low Saxon varieties between the 1980s and 2020s. This included comparing their similarity to Standard Dutch over time. Speakers in 32 locations in both periods translated a Standard Dutch word list into their local dialect. The corresponding recordings were transcribed and consequently analyzed using the Levenshtein distance. We found evidence of regiolect formation in the Frisian and northern Low Saxon areas. Strong convergence to Standard Dutch was found in the areas bordering the Hollandic dialect area and one area in the province of Overijssel. An in-depth analysis showed that low- and high-frequency words were most likely to change and that speaker characteristics interact with convergence and divergence patterns. The findings confirm the importance of including multiple speakers per dialect location and accounting for speaker characteristics in dialectological research.
