Weekly Hydro-meteorological Report, 07 May, 2014

Highlights

Monitoring and Prediction
Existing rainfall condition shall increase till 11th May and for most of the regions significant rainfall events are likely to experience during 9th-13th May 2014. Thereafter rainfall shall decrease gradually. However, during 5th-10th May North, North-eastern and Southern districts shall receive heavy rainfall and Galle district is likely to expect significant heavy rainfall (150-200 mm/6 days)

Download Full Report




Summary

Monitoring


Weekly Monitoring:During 28th April-5th May 2014, Sri Lanka received rainfall ranged 5-50 mm. The maximum amount of rainfall observed for Anuradhapura district on 2nd May and on the same day entire country received rainfall.


Monthly Monitoring:The border regions of Kurunegala and Anuradhapura and, Vavuniya and Mannar districts received above normal rainfall during April 2014 and rest of the districts received below normal rainfall during April 2014.

Predictions

14-day prediction:During 6th-12th May 2014, rainfall shall vary between 5-65 mm/day and amount of rainfall shall increase towards southwestern regions of Sri Lanka. During 13th-19th May 2014, entire country shall receive less than 55 mm/day of rainfall and shall spread from central hills to surrounding districts in a reducing manner.

IMD WRF Model Forecast & IRI forecast: For 8th & 9th of May, IMD WRF model predicts less than 1 mm/day of rainfall central hills and nearby districts and shall increase towards coastal regions of Sri Lanka. For the same days North, North-eastern and Southern districts shall receive less than 36 mm/day of rainfall. IRI model predicts 150-200 mm/6 days of rainfall for Galle district and amount of rainfall shall decrease towards north-east direction (5th-10th May 2014).

1 Month Prediction:Overall-Existing rainfall condition shall increase till 11th May and significant rainfall event is likely to experience during 10th-12th May 2014. Thereafter rainfall shall decrease gradually during prediction period (7th-14th May 2014). Western Slopes- The rainfall pattern persisting in the entire country shall observe in this region with high amount of rainfall. Western Coast- The rainfall pattern persisting in the entire country shall observe in this region. But significant rainfall event is expected during 9th-11th may 2014. Eastern Slope- The rainfall pattern persisting in the western coast region shall observe in this region. Eastern Coast- Existing rainfall shall increase gradually till 10th May and remain more or less constant during the prediction period. Northern- The rainfall pattern persisting in the entire country shall observe in this region. Southern Region- The rainfall pattern persisting in the entire country shall observe in this region, but significant rainfall event is likely to observe during 11th-13th May 2014.

Seasonal Prediction:As per IRI Multi Model Probability Forecast issued on April 2014; for May 2014 to July 2014, there is a 45-55% probability for temperature to be above normal in the country while the rainfall is to be climatological.

PACIFIC SEAS STATE April 17, 2014 :During March through mid-April the observed ENSO conditions moved from cool-neutral to warm-neutral. All of the ENSO prediction models indicate a warming trend, with neutral ENSO during northern spring 2014 transitioning to El Niño conditions by the middle of northern summer.
INDIAN OCEAN STATE :Eastern seas of Sri Lanka showed +0.50C anomaly during 27th April-3rd May 2014.
MJO STATE :MJO is neutral.