Dhaka, the capital of Bangladesh, lies in the centre of the country in the vast Ganges–Brahmaputra delta, just north of the Tropic of Cancer at approximately 23.81°N, 90.41°E. It has a tropical monsoon climate (Köppen Aw) with three clear seasons: a warm, dry winter, a hot and increasingly humid pre-monsoon spring, and a hot, wet monsoon. Nearly 80% of the year's rain falls in the monsoon months.

The hottest time is the pre-monsoon period from March to May, when average highs climb into the mid-30s°C and the record has reached 40°C or more, with mounting humidity making the heat stifling. This season brings violent 'nor'wester' thunderstorms sweeping down from the Himalayas, often with hail and squalls. The monsoon proper, from June to September, keeps temperatures around 29–32°C but with oppressive humidity, heavy cloud and frequent downpours, and flash flooding is a near-annual event in the low-lying city.

Winter, from December to February, is the pleasant, dry season. January, the coolest month, averages daytime highs around 24–26°C and comfortable nights near 13–15°C, though northerly winds can occasionally push nights down toward 7–11°C during cold spells. Morning fog is common in December and January, and with little rain and a stable atmosphere the city's air pollution tends to peak at this time.

Dhaka is very wet, receiving roughly 1,900–2,000 mm of rain a year, the overwhelming majority of it between May and September. June and July are typically the wettest months, and extreme single-day totals are possible — the city once recorded over 340 mm in 24 hours. The dry season from November to March sees almost no rain at all. Live rainfall, humidity, and pressure readings for the city are shown in the panels above.

Bangladesh is highly exposed to tropical cyclones spinning up from the Bay of Bengal, which most often strike just before and just after the monsoon, in late April to June and again in October and November, sometimes bringing destructive winds, torrential rain and storm surge. The country is also one of the most tornado-prone in the world, and its low elevation makes Dhaka and the surrounding delta acutely vulnerable to flooding.

To follow any single measurement in Dhaka more closely, use our live instruments: the online barometer for atmospheric pressure, the thermometer for temperature, the hygrometer for humidity, the anemometer for wind speed, the wind vane for wind direction, and the rain gauge for rainfall.