- The IRI weekly rainfall forecast predicts extremely heavy rainfall in the southern coastal regions during 6-11 Sep.
- Between 30 Aug - 4 Sep: Rainfall up to 50 mm was recorded in Kurunegala district on the 2nd.
- From 27 Aug - 2 Sep: minimum temperature of 20 OC was recorded from Nuwara Eliya district while eastern coastal regions of the island recorded a maximum temperature between 30-35 OC.
- From 29 Aug - 4 Sep: up to 20 km/h, northwesterly winds were experienced by the southern regions of the country; and up to 18 km/h in the central and northern regions.
- Average sea surface temperature was observed in the seas around Sri Lanka.
Download Full Report
Weekly Monitoring: On August 30th, Jaffna district received up to 20 mm of rainfall; and Kilinochchi, Mannar, Mullaitivu, Vavuniya, Ampara, Badulla and Monaragala districts up to 10 mm. On the 31st Mullaitivu, Vavuniya, Puttalam, Anuradhapura and Kurunegala districts received up to 40 mm of rainfall; Mannar, Polonnaruwa, Matale and Ratnapura districts up to 30 mm; Kilinochchi, Trincomalee, Badulla and Galle districts up to 20 mm; and many parts of the island up to 10 mm. On September 1st Kalutara, Ratnapura, Galle and Matara districts received up to 30 mm of rainfall; and Mannar, Vavuniya and Hambantota districts up to 20 mm. On the 2nd Kurunegala district received up to 50 mm of rainfall; Puttalam, and Kegalla districts up to 30 mm; Anuradhapura, Polonnaruwa, Batticaloa, Matale, Ampara, Kandy, and Gampaha districts up to 20 mm; and many parts of the island up to 10 mm. On the 3rd Kalutara, Ratnapura, Galle, Matara, Kegalla and Ampara districts received up to 10 mm of rainfall. On the 4th Vavuniya, Colombo, Kalutara, Galle, Hambantota, Kandy, Nuwara Eliya and Badulla districts received up to 30 mm; and Gampaha, Kegalla, Matale, Ratnapura, Matara and Monaragala districts up to 20 mm.
Total Rainfall for past week : The RFE 2.0 tool shows total rainfall of 75-100 mm in Anuradhapura district; up to 50-75 mm in Vavuniya, Puttalam, Kurunegala, Matale, Nuwara Eliya, Kegalla, Gampaha, Colombo and Ratnapura districts; and 25-50 mm in many parts of the island. It shows above average rainfall up to and 50-100 mm in Puttalam, Kurunegala, Vavuniya and Anuradhapura districts; and up to 25-50 mm Mannar, Matale, Polonnaruwa, Kandy and Nuwara Eliya districts. It also shows below average rainfalls up to 10-25 mm in Matara district.
Monthly Monitoring: During August - below average rainfall conditions were experienced in the southern and western regions of the island and above average rainfall in northern and eastern regions. Gampaha, Colombo, Kalutara, Galle, Matara, Kegalla, Nuwara Eliya and Hambantota districts received up to 150 mm below average rainfall. Batticaloa, Ampara and Monaragala districts received up to 180 mm of above average rainfall; and Mannar, Anuradhapura, Polonnaruwa, Trincomalee, Ampara and northern regions of Puttalam and Badulla districts up to 150 mm. The CPC Unified Precipitation Analysis tool shows ~300 mm of total rainfall in Batticaloa, Polonnaruwa, Monaragala, Badulla, Ratnapura, Anuradhapura and Ampara districts; up to ~200 mm in Trincomalee, Puttalam, Matale, Kandy, Kalutara and Galle districts; up to 100 mm in Jaffna, Kilinochchi, Mullaitivu, Kurunegala, Matara and Hambantota districts; and up to 50 mm in many parts of the island.
NOAA NCEP Models:
From 6th – 12th Sep: Total rainfall between 125-135 mm in Batticaloa and Ampara districts; between 115-125 mm Polonnaruwa district; between 95-105 mm in Galle, Hambantota, Monaragala, Badulla and Trincomalee districts; 85-95 mm in Ratnapura and Nuwara Eliya districts; and 75-85 mm in Kegalla and Kandy districts.
From 13th – 19th Sep: Total rainfall between 45-55 mm in Batticaloa and Ampara districts; and between 35-45 mm in Polonnaruwa district.
IMD WRF Model Forecast & IRI forecast:
8th Sep: Up to 64 mm of rainfall in Puttalam, Gampaha, Colombo, Kalutara and Ratnapura districts; up to 36 mm in Puttalam, Kurunegala, Colombo, Kegalla, Nuwara Eliya, Galle and Matara districts; and up to 8 mm in the rest of the island.
9th Sep: Up to 64 mm of rainfall in Puttalam, Kurunegala, Gampaha, Colombo, Kegalla and Ratnapura districts; up to 36 mm Kandy, Nuwara Eliya, Galle, Matara and Hambantota districts; and up to 8 mm in the rest of the island.
Ocean State (Text Courtesy IRI)
PACIFIC SEAS STATE : August 18, 2017
In mid-August 2017, the tropical Pacific remained in an ENSO-neutral state, with near-average SSTs in the east-central tropical Pacific and the atmosphere also maintaining ENSO-neutral patterns. The collection of latest ENSO prediction models indicates ENSO-neutral as the most likely condition through Northern Hemisphere fall and into winter with chances for El Niño or La Niña development less than one-half that for neutral.
INDIAN OCEAN STATE : Average sea surface temperature was observed in the seas around Sri Lanka.
MJO STATE : MJO shall not have a significant impact on the rainfall in Sri Lanka.