Weekly Monitoring: From 22nd May -29th May rainfall ranged between 5-145 mm. During the week heavy rainfall was observed for the South-western regions of the island. On 22nd & 29th May, no rainfall was recorded compared to the rest of the days in the week.
Monthly Monitoring: During the month of April, the entire island has shown an above average rainfall.
7 Day Prediction: For the coming week, an accumulated rainfall of 5 - 55 mm is predicted for the South-western regions of the island, and 5 – 35 mm is predicted for the entire island.
IMD WRF Model Forecast & IRI forecast: For the 1st of June 2012, WRF Model Predicts less than 65 mm rainfall for Kalutara district. The rainfall shall spreads towards Colombo, Gampaha, Kegalle, Ratnapura, Galle and Matara districts with a decreasing pattern. The WRF Model Predicts the same pattern of rainfall to continue on 2nd June 2012 for the above mentioned regions. IRI models forecast 5 - 25 mm of rainfall for the entire country.
1 Month Prediction: Overall, from 30th May - 02nd June 2012, rainfall shall increase drastically; then shall decrease gradually till the 16th June with minor fluctuation between 09th-06th June. There onwards rainfall shall increase gradually. Western Slopes- Rainfall predicted for western slopes is high compared to the other regions of Sri Lanka. A rapid increase of rainfall shall be expected during 30th May -02nd June and shall decrease gradually till 16th June with minor fluctuations during 04th-05th June and 09th-12th June. Then rainfall shall increase gradually. Eastern Slopes- Rainfall shall increase during 30th May - 01st June and shall gradually decrease till it reaches minimum predicted daily rainfall of 3 mm on 14th June. Thereafter rainfall shall increase drastically. Northern Region- Rainfall shall increase during 30th May - 02nd June and shall decrease till 07th June with the same rate. Rainfall shall be constant from 07th - 12th June 2012 and thereafter rainfall shall increase gradually.
Seasonal Prediction: As per IRI Multi Model Probability Forecast for June 2012 to August 2012, issued in May 2012, there is a 45%-50% probability for temperature to be above normal for the country. There is 40% probability for rainfall to be climatological.
Inside this Issue
a. Daily Satellite Derived Rain fall Estimates
b. Monthly Rain fall Estimates
c. Decadal (10 Day) Satellite Derived Rainfall Estimates
d. Weekly Average SST Anomalies
a. NCEP GFS Ensemble 1-7 day predictions, NOAA, CPC,USA
b. IMD WRF Model Forecast
c. Weekly precipitation forecast (IRI)
d. 1 month experimental predictions by Paul Roundy and L. Zubair
e. Seasonal Predictions from IRI