Dhaka:Bangladesh is expected to face four to six mild to moderate cold waves from November to January, with two to three potentially intensifying into severe cold waves, as forecasted by the Bangladesh Meteorological Department (BMD).
According to Bangladesh Sangbad Sangstha, the BMD's latest three-month long-range forecast also indicates the formation of two to four low-pressure systems over the Bay of Bengal, with the possibility of one or two developing into cyclones. Cooler nights and early mornings are already signaling the onset of winter, particularly in northern villages.
The BMD report, signed by Md. Mominul Islam, notes that one or two mild cold waves may occur in December. BMD Meteorologist Dr. Muhammad Abul Kalam Mallik highlighted that the cold waves will be more pronounced in the northern and western regions of Bangladesh, where temperatures might drop to 8-10 degrees Celsius. In January, moderate and possibly severe cold waves could see temperatures falling to 4-6 degrees Celsius.
The BMD classifies temperatures of 8-10 degrees Celsius as a mild cold wave, 6-8 degrees as moderate, and 4-6 degrees as severe, with temperatures below 4 degrees Celsius considered extremely severe. The forecast also predicts moderate to dense fog in river basins and light to moderate fog elsewhere, which may affect temperature differences between day and night.
Dr. Mallik attributes the chance of a warmer winter to El Niño conditions and global temperature increases, which are impacting South Asia. Although cold waves are predicted, their overall impact may be limited.
Regarding cyclones, Dr. Mallik mentioned that October and November are typically cyclone-prone months, with low-pressure systems over the Bay of Bengal potentially intensifying into cyclones. The BMD forecast also predicts normal rainfall for November to January, with varying amounts across different regions.
The BMD's long-range forecast incorporates meteorological data and climate models, considering El Niño and La Niña conditions. Dr. Mallik warned of the uncertainty inherent in long-range forecasts and advised the public to follow daily weather updates. Bangladesh experienced 68 percent less rainfall than normal in October.