Highlights

Predictions: From 29 Mar – 4 Apr, the US NOAA Climate Prediction Center predicts that the rainfall shall increase throughout SL. During this period, Western Hills & Plains are predicted to receive rainfall ranging from 15-25 mm. From 31 Mar – 6 Apr, wind speeds are predicted to be 1-2 m/s. The Met Ddepartment has issued a heat advisory on 1 Apr, indicating that the temperature levels are likely to increase up to ‘Caution level’ (34 – 35 °C) in SL except in Central Province and Badulla District.
 
Monitoring: Even though March is typically a dry month, it is consequencial to eco-systems and wildlife. During the month of March, SL received only half of the expected rainfall (expected: 62 mm, received: 31 mm). During 25-30 Mar, the average daily rainfall was 0.2 mm with significant rainfall only occuring on two days: Ratnapura on 30 Mar – 33 mm, Anuradhapura on 30 Mar – 6 mm. The highest daily rainfall was in Ratnapura on 30 Mar – 10 mm. During 22 – 28 Mar, winds were from Northeast with 3–5 m/s. Overall the temperature was typical for March across SL. The Southern plains had an average maximum temperature of 34.6°C. The Western Hills had an average minimum temperature of 16.2°C.
 

Raifall Prediction: From 29 Mar – 4 Apr,  rainfall is predicted to  increase throughout SL:  15-25 mm is predicted for  the Western Hills &  Western Plains; 0-15 mm  is predicted for the rest of SL From 5 – 11 Apr, rainfall shall continue to increase:  25-35 mm is predicted for  the Western Hills, 15-25  mm is predicted for the  Western Plains and 0-15  mm is predicted for the  rest of SL. (Source: NOAA  CPC)

Monitored Rainfall: Even though March is  typically a dry month, it is  consequential to Eco –  systems and wildlife. During the month of  March, SL received only  half of the expected  rainfall (expected: 62 mm,  received: 31 mm). During 25-30 Mar, the  average daily rainfall was  0.2 mm with significant  rainfall only occurring on  two days: Ratnapura on  30 Mar – 33 mm,  Anuradhapura on 30 Mar –  6 mm.

Monitored Land & Sea Temperature:  During 25-30 Mar, maximum average temp in SL was 33.3°C, higher compared to the previous week – 32.7°C. Eastern Hills & Western Hills had the lowest temperatures – 28.8°C & 31.3°C .The sea surface temperature around Western and Northern coasts was above the seasonal average by 1°C – 1.5°C, while it was above the seasonal average by 0.5°C – 1.0°C around the other coasts.

 

Monitored & Predicted Wind: Typical wind reversal in late March from Northeast to Southwest is ongoing. From 22 – 28 Mar 2026, winds at 1.5 km elevation were mostly from the Northeast at 3  – 5 m/s.  From 31 Mar – 6 Apr 2026, winds are predicted to slow ( 1-2 m/s from the Southwest).



Terminology for Rainfall Ranges

TerminologyRainfall (mm/week)
Light ShowersLess than 12.5 mm
Light to ModerateBetween 12.5 mm and 25 mm
ModerateBetween 25 mm and 50 mm
Fairly HeavyBetween 50 mm and 100 mm
HeavyBetween 100 mm and 150 mm
Very HeavyMore than 150 mm