Bihar Weather: What to Expect This September

If you live in Patna, Gaya or any part of Bihar, September feels like a bridge between summer’s scorch and winter’s chill. This month you’ll see daytime temps swinging between 27°C and 34°C, while evenings stay muggy around 22°C‑26°C. The humidity stays high, so even a 30°C day can feel oppressive. The good news? Nights give a little relief, and the heat peaks early in the month before tapering off toward the end.

Why does this matter? Simple – you can plan your work, travel and outdoor activities around the real weather, not the vague “summer” label you see on generic forecasts. Below we break down the biggest weather drivers for September 2025 in Bihar and give you quick, actionable tips.

Heat Wave Outlook

Early September still carries the tail end of the seasonal heat wave. Expect the hottest days around the 1st‑5th, with maximums pushing 33°C‑34°C in places like Patna and even hitting 37°C in interior districts such as Aurangabad. If you’re out for a morning run or a market visit, aim for the cool window between 6 am and 9 am. Carry a water bottle, wear light cotton, and avoid direct sun after 10 am.

Heat‑related health issues spike during these peak days. Stay hydrated, limit caffeine, and keep a fan or air‑conditioner on if you’re indoors. If you have children or elderly relatives, check their comfort level regularly – a quick skin‑check for excessive sweating is a lifesaver.

Rain Chances and Tips

Mid‑September brings a noticeable shift. The forecast shows 8‑15 rainy days across Bihar, with a 50% chance of a measurable shower around the 20th‑22nd. Gaya could see a sudden downpour that lasts a few hours, while Patna will have more scattered, lighter rain. These rains are usually short but intense, so keep an umbrella or waterproof jacket handy.

Rain also means higher water levels in the Ganges and its tributaries. If you’re planning a riverfront visit or a drive near low‑lying roads, check local alerts for possible flooding. For farmers, the rain is a blessing – it should help replenish soil moisture after a dry start to the season.

Practical tip: When rain hits, traffic often slows down dramatically. If you need to commute, leave a few minutes earlier than usual and consider alternative routes. Also, keep your mobile charger and important documents in a zip‑lock bag to avoid water damage.

Overall, September in Bihar is a mix of lingering heat and refreshing rain. By syncing your daily routine with the early‑morning cool, staying hydrated during the hot spell, and keeping an eye on rain forecasts, you’ll navigate the month comfortably. Keep this page bookmarked – we’ll update the forecasts as new data arrives, so you always have the freshest info at your fingertips.