Media Center
Climate Bulletin for Sri Lanka (Week of 12 – 19 Nov 2021)
Highlights
Rainfall Prediction: Heavy rainfall is predicted for North Western, Western and Sabaragamuwa provinces from 12th Nov – 16th Nov. Greater likelihood of wet tendency is predicted for Sri Lanka from Nov to Jan.
Monitored Rainfalls: Heavy rainfall was experienced in Northern, North Central, North Western, Sabaragamuwa and Western provinces with max of 300.4 mm in Anuradhapura district on 8th Nov.
Monitored Wind: From 1st Nov – 8th Nov, up to 30 km/h Westerlies to Northwesterlies were experienced across the island.
Monitored Sea Surface: Sea surface temperatures were above 1.00C in the Northern and Western seas while 0.50C in the Eastern and Southern seas around the island.
Interpretation
Monitoring
Rainfall: During the last two weeks, there had been very heavy rainfall over the following Provinces: Northern, North Central, North Western, Sabaragamuwa and Western.
Wind: Westerly to North Westerly winds prevailed in the sea area and around the island last week.
Temperatures: The temperature anomalies were near-neutral for the entire island last week, driven by the warm SST’s.
Prediction
Rainfall: During the next week (12th November – 16 th November) heavy rainfall is predicted for the following provinces: North Western, Sabaragamuwa and Western.
Temperatures: The temperature remains slightly normal during 12th November – 20th November for the entire island.
Teleconnections: La Nina -The SST forecast indicates that ENSO-neutral are present and a transition from ENSO-neutral to La Niña is favored in the next couple of months.
During 10th November – 14th November MJO shall be active giving enhanced rainfall in the North while neutral for the rest of the island. During 15th November – 19th November MJO shall be active giving slightly suppressed rainfall and from 20th November – 24th November giving severely suppressed rainfall.
Seasonal Precipitation:
The precipitation forecast for the Nov-Jan season show enhanced probabilities of above-normal precipitation over Sri Lanka.
Understanding the Forecast
| Rainfall (During 24 hours of period) | |
| Light Showers | Less than 12.5 mm |
| Light to Moderate | Between 12.5 mm and 25 mm |
| Moderate | Between 25 mm and 50 mm |
| Fairly Heavy | Between 50 mm and 100 mm |
| Heavy | Between 100 mm and 150 mm |
| Very Heavy | More than 150 mm |
