Only two months ago, Bangladesh was experiencing one of the hottest periods of the year. Heatwaves swept across many districts, and people were advised to stay indoors. Driven by changing global climate systems, the Bangladesh Meteorological Department (BMD) had predicted an intense dry period for this year. Ten more heatwaves were predicted to occur between June and August.
While the BMD later flagged standard early-July warnings of heavy rainfall due to a monsoon depression, few could have anticipated the sheer violence of the downpour. What followed was a period of torrential, July brought days of torrential rainfall that swelled rivers, inundated roads, and plunged major parts of the country into severe flooding and waterlogging, leaving people completely unprepared for the devastation.
For many people, this raised an obvious question: What is happening to our weather?
Some may see these events as isolated incidents, but they are part of a much larger pattern. Climate change is not only increasing temperatures; it is making weather patterns increasingly irregular. Bangladesh is gradually moving from a climate where seasons followed a familiar rhythm to one where weather is becoming much harder to anticipate.
A few decades ago, life in Bangladesh followed a seasonal calendar that people understood well. Farmers prepared their land knowing roughly when the monsoon would arrive. Aman rice was transplanted according to expected rainfall, while wheat, mustard, potatoes and vegetables were planted after winter set in. Fishermen understood seasonal river conditions, and even many social and cultural activities were organised around predictable weather patterns.
Of course, weather was never perfectly consistent. There were floods, droughts and cyclones. But these were exceptions rather than the norm. Most years, people could rely on the general timing of the seasons. Their knowledge came from experience built over generations.
Today, that confidence is gradually disappearing.
Bangladesh is particularly vulnerable because its economy and livelihoods are closely tied to seasonal weather. Agriculture still employs millions of people, and crop production depends heavily on the timing of rainfall and temperature.
Rain often arrives later than expected, or sometimes much earlier. Heavy rainfall may occur within just a few days instead of being distributed across several weeks. Winters are becoming shorter and warmer. Heatwaves are arriving earlier and lasting longer. Instead of one predictable seasonal cycle, Bangladesh is increasingly experiencing sudden shifts between prolonged dry conditions and intense rainfall.
The recent heavy rainfall in July illustrates this change. After months of extreme heat, many people welcomed the rain, expecting relief from the scorching temperatures. Yet the rainfall was so intense that it caused flooding and waterlogging in many places. This shows that the challenge is no longer simply whether it rains, but when, how much, and how quickly the rain falls.
Why is this happening?
The underlying cause lies in how climate change affects the Earth's atmosphere. On a global scale, scientists attribute this phenomenon to the intensification of the hydrological cycle caused by global warming. As greenhouse gas emissions continue to warm the planet, the atmosphere becomes warmer and capable of holding more moisture. This changes the entire water cycle. More water evaporates from rivers, ponds, wetlands and the soil. As a result, rainfall is becoming more concentrated, with intense downpours occurring over a short period and longer dry spells in between.
Data from the BMD reveals that the country’s traditional monsoon schedule is actively shifting. June, which traditionally marks the arrival of steady monsoon rains, has increasingly recorded below-average rainfall; nearly 30 per cent less than normal this year. Combined with persistently high temperatures, these dry conditions allowed heat to build up. When rain finally arrived in July, much of the seasonal rainfall fell within a short period, leading to flooding and waterlogging in many parts of the country.
Bangladesh is particularly vulnerable because its economy and livelihoods are closely tied to seasonal weather. Agriculture still employs millions of people, and crop production depends heavily on the timing of rainfall and temperature. When seasons become irregular, farming becomes much more difficult.
For instance, in northwestern Bangladesh, one of the country's drought-prone regions, many people no longer trust the traditional agricultural calendar. They know that summers are becoming hotter, but their greatest concern is uncertainty. Rain sometimes arrives too late for cultivation. At other times, heavy rainfall damages crops just before harvest.
Heatwaves dry out the soil rapidly, increasing irrigation needs, while sudden downpours often fail to compensate for the earlier moisture loss because much of the water runs off quickly instead of replenishing the soil and groundwater. These sufferings are also experienced by farmers in coastal areas, and floodplains. Although the challenges differ from one region to another, the underlying problem is the same: weather patterns are becoming less reliable.
This growing unpredictability has consequences beyond agriculture. It affects water management, fisheries, transport, public health and even household finances. When heavy rainfall occurs unexpectedly, cities experience waterlogging because drainage systems cannot cope with such intense rainfall. When heatwaves become longer, electricity demand rises while outdoor workers face greater health risks. Every sector is forced to deal with greater uncertainty.
Perhaps the biggest challenge is that Bangladesh's climate policies still tend to treat floods, droughts and heatwaves as separate problems. In reality, they are increasingly connected. A prolonged heatwave can dry out the soil, followed by intense rainfall that causes flooding instead of slowly replenishing water resources. One climate extreme often creates the conditions for another.
This means that adaptation strategies must also change. Bangladesh certainly needs stronger embankments, better drainage systems and improved irrigation. However, it also needs better seasonal forecasting, climate information services for farmers, improved groundwater management, crop insurance and stronger local planning that recognises increasing climate variability.
Climate change is often described as a problem of rising temperatures. That description is no longer enough. The greater challenge facing Bangladesh today is the growing unpredictability of its weather. It is not simply that summers are hotter or rainfall is heavier. It is that the natural rhythm on which people have depended for generations is gradually breaking down.
The recent July rainfall should therefore not be seen as an isolated weather event. It is another reminder that Bangladesh is entering a new climatic reality. Learning to live with this reality will require more than disaster response. It will require rethinking how we plan our agriculture, manage our water resources and prepare our communities for a future where uncertainty itself has become one of the greatest consequences of climate change.
* Ummey Kulsum is a lecturer at the Department of Geography and Environmental Studies, University of Rajshahi.