Chittagong weather in September

Forum posters describe July as very hot and squarely within Bangladesh's monsoon season, with heavy rainfall and a real risk of localized flooding, particularly in low-lying areas. Posters flag Chittagong specifically as prone to flooding during heavy rain events, and consistently recommend carrying waterproof poly bags to protect phones, wallets and other electronics from sudden downpours. Posters generally name late October through early March as the far better overall window for Bangladesh, implicitly framing July as one of the more challenging months to visit given the combination of intense heat and disruptive rain. Posters generally rate July as visitable only with real weather-contingency planning, given both the heat and the genuine flood risk around Chittagong specifically.

Chittagong forum regulars, drawing on the same Bangladesh-wide conversation as Dhaka, call January the perfect time to visit, pleasant weather that's not humid at all — though a late winter can occasionally bring a cold, foggy stretch. December and January together get named as the ideal travel window: no rain, full blossom of winter, neither the summer heat nor the monsoon humidity in play. Anyone heading into the Chittagong Hill Tracts specifically needs a local guide and a permit from the Deputy Commissioner's office in the city, obtainable on a weekday morning before 11am — a logistics note as important as the weather for that particular trip. Our record: 24.3°C days, 16°C nights, just 1.2 rain days and an AQI of 126 — mild and dry, matching the “perfect, not humid” read, with the AQI figure the one thing the pure weather praise leaves out.