Climate Bulletin For Sri Lanka (13 January 2023)

             

Highlights          

 • Fairly heavy rainfall is predicted for the Southern province and moderately heavy rainfall is predicted for the rest of the country during 12th - 18th January. The seasonal forecast shows a higher tendency for above-normal precipitation from January - March, 2023.

 • During the last week, maximum daily rainfall over Sri Lanka was 80.0 mm and hydro catchment areas received 53.7 mm.

 • From 3rd - 9th Jan, up to 10m/s of north easterly winds were experienced at 850 mb level over the island. During 13th - 19th Jan, easterly winds are expected for the country.

 • Sea surface temperature around Sri Lanka was near-neutral  for the entire island. Land surface temperature remained near normal. 

Download full report ↓

---

Predictions

Rainfall

14-day prediction: 
NOAA NCEP models: 

From 12^th January – 18^th January:

Total rainfall by Provinces:   

•  55 mm - Southern
•  45 mm - Sabaragamuwa, Eastern
•  35 mm - Central, Uva, Western, North Central
•  ≤ 25 mm - North Western, Northern

From 19^th January – 25^th January:

Total rainfall by Provinces:   

• 105 mm - Eastern
•  95 mm - Central, Uva
•  85 mm - North Central
•  75 mm - Sabaragamuwa, Southern, North Western
•  65 mm - Western
•  55 mm - Northern

MJO based OLR predictions:

For the next 15 days: 

MJO shall slightly enhance the rainfall during 12^th – 16^th January, moderately enhance the rainfall during 17^th – 21^st January, and highly enhance the rainfall during 22^nd – 26^th January for Sri Lanka.

Ocean State (Text Courtesy IRI)

Pacific Sea Sate: January 9, 2023 

Equatorial sea surface temperatures (SSTs) are below average across most of the Pacific Ocean early - January. The tropical Pacific atmosphere is consistent with La Niña. A large majority of the models indicate La Niña is favored to continue into the winter, with equal chances of La Niña and ENSO-neutral during January-March 2023. In February-April 2023, there is a 71% chance of ENSO-neutral.

Indian Sea Sate

Sea surface temperature around Sri Lanka was near neutral for the whole country in 4^th January, 2023. Across the Indian Ocean, a classical negative Indian Ocean Dipole prevails as is typical during a La Niña.

 

Interpretation

Monitoring

Rainfall: 

During the last two weeks, there had been heavy rainfall over the following areas: Galle, Kalutara

Daily Average Rainfall in the Met stations for previous week of (4^th January – 11^th January) = 4.3 mm

Rmax: 80.0 mm & Rmin: 0.0 mm.

Region	Average rainfall for the Last 8 days
Northern Plains	6.0 mm
Eastern	4.0 mm
Western	3.9 mm
Southern Plains	0.4 mm

The Hydro Catchment Areas recorded 5.3 mm of average rainfall for the last week
Rmax: 53.7 mm & Rmin: 0.0 mm.

Wind:

North easterly winds prevailed in the sea area and around the island last week.

Temperature: 

The temperature anomalies were below normal for some parts of the Central, North Western, and North Central provinces, driven by the warm SST’s.

Predictions

Rainfall:

During the next week (12^th – 18^th January), fairly heavy rainfall (≥ 55 mm) is predicted for the Southern province; and moderately heavy rainfall is expected for the Sabaragamuwa, Eastern, Central, Uva, Western, North Central and less rainfall is expected for rest of the country.

Temperature:

The temperature will remain below normal for some parts of the Central, Uva, and Sabaragamuwa provinces during 13^th – 19^th January.

Teleconnections:

La Niña is favored to continue into the winter, with equal chances of La Niña and ENSO-neutral during January-March 2023.

MJO shall slightly enhance the rainfall during 12^th – 16^th January, moderately enhance the rainfall during 17^th – 21^st January, and highly enhance the rainfall during 22^nd – 26^th January for Sri Lanka.

Seasonal Precipitation: 

The precipitation forecast for the January-February-March 2023 season shows a higher tendency of above-normal precipitation for the country.