September in Middletown averages a daily high of 25.9°C with nights around 14°C. Expect roughly 9 wet days totalling 109.2mm. Comfortable conditions for being outdoors all day.
Across the year, the best time to visit Middletown is May–June.
Based on FREEHOLD MARLBORO, NJ US (14.5km), 1995–2024. 26 years of September data.