Thundershowers unprecedented during current Monsoon

• This year’s monsoon has seen a shift in rainfall patterns, with a significant increase in precipitation compared to last year and increased variability in monsoon patterns

By Leenah Wahab   

The Meteorological Department issued a weather advisory yesterday warning of heavy showers above 50 mm in areas within the Western, Sabaragamuwa and North-western provinces and in Galle and Matara districts.   

According to the weather alert, strong winds of 40- 50 kmph are expected over Western slopes of the central hills, Northern, North-central and North-western provinces and in Hambantota, Monaragala and Trincomalee districts.   

Forecasts predict that Ampara and Batticaloa districts will face thundershowers in the evening or night. Citizens residing in Kandy, Nuwara- Eliya and Matara districts have also been requested to heed caution ahead of incoming thundershowers and take adequate precautions to minimise damages caused by temporary localized strong winds and lightning.   

Director of Climate Change Studies at the Department of Meteorology, Ms. Warnasooriya said this year’s monsoon has seen a shift in rainfall patterns, with a significant increase in precipitation compared to last year and increased variability in monsoon patterns.   

According to a report by the Global Facility for Disaster Reduction and Recovery (GFDRR), records analyzed from 1974-2004 indicate that floods are increasing, with the South West Monsoon causing severe flooding in the western and south-western provinces.   

A study conducted by Professor Alahakoon at the International Water Management Institute on spatial variability of rainfall trends as an indication of climate change found that there has been a significant increase in annual rainfall from 1989 to 2019 in all climatic zones (wet, dry, intermediate, and Semi-arid) of Sri Lanka.   

However, Ms. Warnasooriya said these changes in rainfall patterns cannot yet be attributed to the effects of global warming. “It is too early to say, we must consult 30-year data in order to determine significant changes in climate conditions,” she said.