Climate Bulletin For Sri Lanka (1 April 2022)

Highlights          

                   

 • From 1st - 6th  April, Moderate rainfall (up to 35 mm) is expected  for the Sabaragamuwa, Western & Southern provinces while less is expected other provinces

 • During the last week the Average Daily Rainfall in Sri Lanka was 2.3 mm, with max of 109 mm in Kalutara on 29th March.

 • From 22nd - 28th March, up to 3m/s Southerlies to South-easterlies  were experienced.

 • Sea surface temperature was above 0.5℃ to the north of Sri Lanka. A La Niña pattern is prevalent in the Pacific Ocean but not in the Indian Ocean. 

Download full report ↓

---

Predictions

Rainfall

14-day prediction: 
NOAA NCEP models: 

From 1^st – 6^th April: 

Total rainfall by Provinces:

• 35 mm - Western, Sabaragamuwa, Southern
• 25 mm - Central, North Western, Eastern, North Central, Uva
• 15 mm - Northern 

From 7^th – 13^th April: 

Total rainfall by Provinces:

• 35 mm - Western, Sabaragamuwa, Southern, Eastern
• 25 mm - North Western, North Central, Uva, Central
• 15 mm - Northern

MJO based OLR predictions:

For the next 15 days: 

MJO shall neutral during 1^st – 4^thApril; slightly enhance the rainfall during 5^th - 9^th April; and moderately enhance during 10^th – 14^th April.

Ocean State (Text Courtesy IRI)

Pacific Sea Sate: March 23, 2022 

Equatorial sea surface temperatures (SSTs) are below average across the East Central and Eastern Pacific Ocean in late-March. The tropical Pacific atmosphere is consistent with La Niña. A large majority of the models indicate La Niña is favored to continue into the Northern Hemisphere summer, with a 40-50% chance of La Niña or ENSO neutral thereafter.

Indian Sea Sate

Sea surface temperature was observed above 0.5℃ to the north of Sri Lanka and neutral to the rest.

Interpretation

Monitoring

Rainfall: 

During the last two weeks, there had been heavy rainfall over the following area: 

Morapitiya (Kalutara)

Daily Average Rainfall in the Met stations for previous week of (22^nd-29^th March) = 2.3 mm

Rmax: 24.4mm & Rmin: 0mm.

Region	Average rainfall for the Last 8 days
Northern Plains	2.2 mm
Eastern	1.1 mm
Western	3.1 mm
Southern Plains	0.04 mm

The Hydro Catchment Areas were recorded 2.7 mm of average rainfall for the last week Rmax: 11.6 mm & Rmin: 0 mm.

Wind:

Southerly to South-easterly winds prevailed in the sea area surrounding the island last week.

Temperature: 

The temperature anomalies were near-neutral for the country, driven by the warm SST’s.

Predictions

Rainfall:

During the next week (1^st – 6^th April) moderate rainfall is predicted for Western, Sabaragamuwa and Southern provinces.

Temperature:

The temperature remains slightly above normal in the Northern and provinces during 1^st – 9^th April. 

Teleconnections:

La Nina - The SST forecast indicates that La Niña is favored to continue into the Northern Hemisphere summer (June-August 2022).

MJO shall neutral during 1^st – 4^thApril; slightly enhance the rainfall during 5^th - 9^th April; and moderately enhance during 10^th – 14^th April.

Seasonal Precipitation: 

The precipitation forecast for the April-May-June season shows above-normal precipitation for the island, while some parts of the southern province remain neutral.