- The IRI weekly rainfall forecast predicts up to 50 mm of total rainfall in Kalutara and Galle districts during 27th Sep - 2nd Oct.
- Between 20 - 26 Sep: Rainfall up to 50 mm was recorded in Anuradhapura and Trincomalee districts on the 23rd.
- From 17 - 23 Sep: minimum temperature of 20 OC was recorded from Nuwara Eliya district while Ampara district recorded a maximum temperature between 35-40 OC.
- From 19 - 25 Sep: up to 54 km/h, northwesterly winds were experienced by the southern half of the country and up to 36 km/h in the northern half.
- 0.5 OC above average sea surface temperature was observed in the northern and eastern seas around Sri Lanka.
Download Full Report
Weekly Monitoring: On September 20th, coastal regions of Colombo, Galle and Matara districts received up to 30 mm of rainfall; and several regions of Kegalla, Gampaha, Nuwara Eliya and Ratnapura districts up to 10 mm. On the 21st Kurunegala, Gampaha, Kandy, Nuwara Eliya, Badulla, Monaragala, Colombo, Kalutara, Galle and Matara districts received up to 10 mm of rainfall. On the 22nd Trincomalee district received up to 10 mm of rainfall. On the 23rd Anuradhapura and Trincomalee districts received up to 50 mm of rainfall; Mullaitivu, and Vavuniya districts received up to 20 mm of rainfall; and many northern parts of the island up to 10 mm. On the 25th Kalutara, Galle, Matara and Ratnapura districts up to 30 mm; and many parts of the island up to 10 mm. On the 26th Kalutara and Galle districts received up to 40 mm of rainfall; Jaffna, Kilinochchi, Gampaha, Colombo and Ratnapura districts up to 20 mm; and many parts of the island up to 10 mm.
Total Rainfall for past week : The RFE 2.0 tool shows total rainfall of 25-50 mm in Anuradhapura, Trincomalee, Gampaha, Kalutara, Ratnapura, Galle and Matara districts; and 10-25 mm in many parts of the island. It shows above average rainfall up to 25-50 mm in the northern regions of Anuradhapura district. It also shows below average rainfall up to and 25-50 mm in Colombo, Gampaha, Badulla and Batticaloa districts; and up to 10-25 mm in many central and southern parts of the island.
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 27th Sep – 03rd Oct: Total rainfall between 35-45 mm in Colombo, Ratnapura and Galle districts; between 25-35 mm Gampaha and Kegalle districts; between 15-25 mm Puttalam, Kurunegala and Matara districts.
From 04th – 10th Oct: Total rainfall between 45-55 mm in Colombo, Ratnapura, Galle and Matara districts; and between 35-45 mm in Gampaha, Kegalla and Matara district; between 25-35 mm in Puttalam, Kurunegala, Kandy and Nuwara Eliya; between 15-25 mm in Anuradhapura, Matale, Badulla, Monaragala, Hambanthota, Jaffna, Kilinochchi and Mannar; Up to 15 mm rainfall in Vavuniya,Polonnaruwa, Trincomalee, Batticaloa and Ampara.
IMD WRF Model Forecast:
29th Sep: Up to 36 mm of rainfall in Mannar, Puttalam, Gampaha, Colombo, Kalutara and Galle districts; up to 8 mm in Matara, Hambanthota, Ratanapura, Kegalla, Kurunegala, Anuradhapura, Vavuniya, Mulativu and Trincomalee districts; and up to 3 mm rainfall in Ampara, Batticaloa, Polonnaruwa, Matale and Monaragala districts.
30th Sep: Up to 36 mm of rainfall in Mannar, Vavuniya, Anuradhapura Puttalam, Gampaha, Colombo, Kalutara and Galle districts; up to 8 mm in Matara, Hambanthota, Ratanapura, Kegalla, Kurunegala, Mulativu and Trincomalee districts; and up to 3 mm rainfall in Ampara, Batticaloa, Polonnaruwa, Matale and Monaragala districts.
IRI Weekly forecast:
20th- 25th Sep: Total rainfall up to 50 mm in northern coastal regions of Jaffna district.
Ocean State (Text Courtesy IRI)
PACIFIC SEAS STATE : September 19, 2017
In mid-September 2017, the tropical Pacific remained in an ENSO-neutral state, although SSTs in the east-central tropical Pacific have cooled to the threshold for La Niña while the atmosphere continues to maintain largely ENSO-neutral patterns. The collection of latest ENSO prediction models indicates coolish ENSO-neutral or weak La Niña as two possible scenarios during Northern Hemisphere fall and winter. The official CPC/IRI outlook slightly favors La Niña development, and carries a La Niña watch.
INDIAN OCEAN STATE : 0.5 0C above average sea surface temperature was observed in the northern and eastern seas around Sri Lanka.
MJO STATE : MJO shall not have a significant impact on the rainfall in Sri Lanka.