Climate Bulletin For Sri Lanka (2 October 2020)

 

              Highlights                             

  •  The NOAA weekly rainfall forecast predicts up to 75 mm in Ratnapura, Colombo, Gampaha and Kegalle districts during 8th -14thOct

  •  Between 24th- 30th Sep up to 180 mm received in Badulla and Moneragala districts

• From 2nd - 8th Oct: North westerly winds up to 10 km/h were experienced in the southern half of the island

• 0.5 0C above average sea surface temperature was observed in the seas around Sri Lanka

Download full report ↓

---

Monitoring

Rainfall

Weekly Monitoring:

Date	Rainfall
24th September	Up to 90 mm in Trincomalee district.
25th September	Up to 30 mm in Galle and Kalutara districts.
26th September	Up to 40 mm in Ampara district.
27th September	Up to 180 mm in Badulla and Moneragala districts.
28th September	Up to 140 mm in Trincomalee district.
29th September	Up to 80 mm in Jaffna district.
30th September	Up to 15 mm in Galle and Matara districts.

Total Rainfall for the Past Week: 

The RFE 2.0 tool shows total up to 150 – 200 mm in Moneragala and Badulla districts; up to 75 – 100 mm in Ampara, Polonnaruwa, Nuwara Eliya, Kegalle, Kalutara, Galle, Trincomalee, Anuradhapura and Jaffna districts; up to 50 – 75 mm in Kilinochchi, Mullaitivu, Mannar, Vavuniya, Matale, Kandy, Batticaloa, Puttalam, Kurunegala, Gampaha, Colombo, Ratnapura and Matara districts; and up to 25 – 50 mm in Hambantota district. 

Above rainfall average up to 100 – 200 mm in Moneragala and Badulla districts; up to 50 – 100 mm in Nuwara Eliya, Ampara, Batticaloa, Trincomalee, Anuradhapura, Polonnaruwa and Jaffna districts; up to 25 – 50 mm in Kilinochchi, Vavuniya, Mannar, Puttalam, Mullaitivu, Kurunegala, Gampaha, Colombo, Kalutara, Galle, Matale, Kandy, Ratnapura, Kegalle and Hambantota districts; and up to 10 - 25 mm in Matara district. 

 

Monthly Monitoring: 

During September – Above average rainfall conditions up to 12 mm in Badulla and Moneragala districts; up to 8 mm in Mannar district; up to 5 mm in Ampara, Polonnaruwa, Batticaloa, Trincomalee, Anuradhapura, Kilinochchi, Mullaitivu, Vavuniya and Jaffna districts; up to 4 mm in Puttalam, Kurunegala, Gampaha, Matale, Kandy, Nuwara Eliya, Ratnapura and Hambantota districts; and up to 2 mm in Colombo, Kalutara, Galle, Matara and Kegalle districts. 

 Predictions

Rainfall

14-day prediction: 

NOAA NCEP models: 

From 1^st October – 7^th October: Total rainfall up to 65 mm in Ratnapura, Colombo and Kegalle districts; up to 55 mm in Galle, Kurunegala and Gampaha districts; up to 45 mm in Puttalam, Matara, Kandy, Nuwara Eliya and Matale districts; up to 35 mm in Hambantota, Moneragala and Badulla districts; up to 25 mm in Ampara district; and up to 15 mm in Polonnaruwa and Anuradhapura districts. 

From 8^th October – 14^th October: Total rainfall up to 75 mm in Ratnapura, Colombo, Gampha and Kegalle districts; up to 65 mm in Galle, Nuwara Eliya, Kandy and Kurunegala; up to 55 mm in Puttalam and Matale districts; up to 45 mm in Matara, Hambantota and Badulla districts; up to 35 mm in Ampara, Polonnaruwa and Anuradhapura districts; up to 25 mm in Batticaloa district; and up to 15 mm in Trincomalee, Vavuniya, Mannar and Jaffna districts. 

 

IRI Model Forecast: 

From 24^th – 29^th September: Total rainfall up to 75 mm in Badulla district; up to 50 mm in Ampara, Moneragala, Ratnapura, Nuwara Eliya, Kandy, Matale, Polonnaruwa, Anuradhapura, Batticaloa, Trincomalee, Vavuniya, Mullaitivu, Kilinochchi and Jaffna districts; and up to 25 mm in Mannar, Puttalam, Kurunegala, Kegalle, Gampaha, Colombo, Kalutara, Galle, Matara and Hambantota districts. 

MJO based OLR predictions:

For the next 15 days: 

MJO shall suppress during 30th Sep -9th Oct and be in phases during 10th – 14th Oct with weak influence. 

Ocean State (Text Courtesy IRI)

Pacific sea state: September 23, 2020 

Equatorial Eastern Pacific SST decreased to near the La Niña threshold in Late-September, and the atmospheric variables were either ENSO-neutral or indicative of weak La Niña conditions. The average of the forecasts of many models just short of the borderline of weak La Niña SST conditions through fall, becoming slightly weaker beginning in early winter. The official CPC/IRI outlook is somewhat similar to these model forecasts, calling for a likely continuation of ENSO-neutral in summer, with approximately equal chances of ENSO-neutral or La Niña for fall and winter. 

Indian Ocean State

0.5 ⁰C above average sea surface temperature was observed in the seas around Sri Lanka.