Weekly Hydro-meteorological Report, 20 March, 2014

Highlights

Monitoring and Prediction
Existing rainfall condition further decrease till 22nd March and remain constant till 28th of March. For western slopes and Southern regions, existing rainfall is likely to increase after 23rd March till 29th March 2014. However, on 21st Kegalle and Ratnapura districts shall receive more rainfall than the entire country. For the coming week (18th-23rd March), Badulla district is likely to expect heavy rainfall.

Download Full Report




Summary

Monitoring


Weekly Monitoring:During 11th-16th March 2014, entire country was dry. On 17th March, Anuradhapura district received insignificant amount of rainfall (less than 5 mm rainfall/day).


Monthly Monitoring:Ratnapura district received the highest average rainfall during February 2014 (more than 5mm/day of average rainfall). However during February 2014, entire country experienced below normal rainfall and highest negative anomaly recorded at Batticaloa and Ampara district.

Predictions

14-day prediction:During 19th-25th March, southwestern regions of the Island shall receive rainfall of less than 55 mm/week. During 26th March-1st April 2014, entire country is likely to expect less than 15 mm/week rainfall.

IMD WRF Model Forecast & IRI forecast: For 21st of March, IMD WRF model predicts high amount of rainfall (less than 65 mm/day) for the parts of Kegalle and Ratnapura districts. For the same day southern 2/3rd of the island shall receive less than 35 mm/day rainfall. For 22nd of March, model predicts less than 65 mm/day rainfall for patches in Colombo, Galle and N’Eliya districts and for the same day western regions shall receive less than 35 mm/day rainfall. IRI model predicts 100-150 mm/6 days of rainfall for Badulla district and rainfall shall spread in a reducing pattern towards near by districts for the coming week (18th-23rd March 2014).

1 Month Prediction:Overall-Existing rainfall condition further decrease till 22nd March and remain constant till 28th of March. Western Slopes- Existing rainfall condition further decrease till 22nd March and it shall increase gradually till 29th March. Western Coasts- The rainfall pattern persisting in the entire country shall be observed in this region. Eastern Slopes- The rainfall pattern persisting in the entire country shall be observed in this region, with high amount of rainfall. Eastern Coast- Existing rainfall condition further decrease gradually till 27th March Northern- Existing rainfall condition further decrease till 23rd March and thereafter rainfall is not predicted till 28th. Southern Region- The rainfall pattern persisting in the western slopes shall be observed in this region.

Seasonal Prediction:As per IRI Multi Model Probability Forecast issued on February 2014; for March 2014 to May 2014, there is a 40-45% probability for temperature to be above normal in the country while the rainfall is to be climatological.

PACIFIC SEAS STATE March 6, 2013 :During January through February the observed ENSO conditions moved to the borderline of cool-neutral and weak La Nina. However, most of the ENSO prediction models continue to indicate neutral ENSO into northern spring 2014. During late spring and summer a warming tendency is seen in both dynamical and statistical models.

INDIAN OCEAN STATE :The seas around Sri Lanka showed neutral sea surface temperature during 9th-15th March 2014.
MJO STATE :MJO is at phase 2 & will move in to phase 3 which shall influence rainfall of Sri Lanka.