Climate Bulletin for Sri Lanka ( 21 November 2019)

                                                      Highlights                                

• The NOAA weekly rainfall forecast predicts up to 100 mm of total rainfall in northern and eastern regions of the island during 20 – 25 Nov
• Between 13 - 19 Nov: up to 70 mm of rainfall was recorded in Anuradhapura, Batticaloa, Gampaha and Colombo districts on the 18th.
• From 12 - 18 Nov: up to 18 km/h, easterly winds were experienced by the entire island.
• 0.5 0C above-average sea surface temperature was observed in the seas around Sri Lanka

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Monitoring

Rainfall

Weekly Monitoring:

Date	Rainfall
13th November	No Rainfall.
14th November	Up to 30 mm in Polonnaruwa district; and up to 20 mm in Kalutara, Puttalam and Batticaloa districts.
15th November	Up to 50 mm in Trincomalee district; up to 30 mm in Kurunegala and Nuwara Eliya districts; up to 20 mm in Mullaitivu, Anuradhapura, Polonnaruwa, Matale, Kandy, Kegalle, Gampaha, Ratnapura, Badulla, Monaragala and Ampara districts; and up to 10 mm most parts of the island.
16th November	Up to 50 mm in Puttalam, Kurunegala and Nuwara Eliya districts; up to 30 mm in Jaffna, Kilinochchi, Mullaitivu, Mannar, Anuradhapura, Polonnaruwa, Matale, Kandy, Colombo, Badulla and Monaragala districts; up to 20 mm in Kegalle, Kalutara, Colombo, Ratnapura, Galle, Hambantota, Ampara and Mullaitivu districts; and up to 10 mm most parts of the island.
17th November	Up to 30 mm in Ratnapura district; and up to 20 mm in Kegalle, Galle, Matara and Nuwara Eliya districts.
18th November	Up to 70 mm in Anuradhapura, Batticaloa, Gampaha, and Colombo districts; up to 60 mm in Kurunegala, Kalutara and Ratnapura districts; up to 50 mm in Puttalam, Kegalle and Polonnaruwa districts; up to 30 mm in Vavuniya, Batticaloa, and Matale districts; and up to 20 mm in Mullaitivu, Kandy, Nuwara Eliya, Badulla, Monaragala and Galle districts.
19th November	Up to 50 mm in Ratnapura district; up to 30 mm in Gampaha, Colombo, Galle and Anuradhapura districts; and up to 20 mm in Puttalam, Kalutara, Matara, Hambantota and Monaragala districts.

Total Rainfall for the Past Week: The RFE 2.0 tool shows total up to 75-100 mm in Puttalam, Kurunegala, Gampaha, Colombo, Kalutara, and Ratnapura districts; up to 50-75 mm in Anuradhapura, Badulla, Nuwara Eliya, Kegalle and Galle districts; and up to 25-50 mm in most parts of the island. Above-average rainfall up to 25-50 mm is shown for Puttalam, Gampaha, Colombo and southern regions of Kurunegala district. Below-average rainfall up to 50-100 mm is shown for Jaffna, Trincomalee, Polonnaruwa, Batticaloa, Kandy and Badulla districts; up to 25-50 mm in most parts of the island.

Monthly Monitoring: During October –Above average rainfall conditions up to 360 mm were experienced by Kilinochchi, Ratnapura, Vavuniya, Anuradhapura, Kurunegala, Matara and Hambantota districts; up to 300 mm in Jaffna district; and up to 240 mm in the rest of the island. The CPC Unified Precipitation Analysis tool shows up to 750 mm were experienced by Colombo and Ratnapura districts; and up to 500 mm in most parts of the island.

Predictions

Rainfall

14-day prediction: 

NOAA NCEP models: 

IMD NCMWRF Forecast:
From 20^th – 26^th Nov: Total rainfall up to 125 mm in Batticaloa and Ampara districts; up to 85-95 mm in Jaffna, Trincomalee, Badulla, Monaragala, Ratnapura, Galle and Matara districts; and up to 75-85 mm in Puttalam, Kilinochchi, Mullaitivu, Kegalle and Hambantota districts.
From 27^th Nov – 3^rd Dec: Total rainfall more than 135 mm in Jaffna, Kilinochchi, Batticaloa and Ampara districts; up to 125-135 mm Mannar district; and up to 115-125 mm in Puttalam, Kurunegala, Ratnapura, Galle, Trincomalee, Polonnaruwa, Badulla and Monaragala districts.

IRI Model Forecast: 
From 20^th – 25^h Nov: Total rainfall up to 100 mm is expected in Jaffna, Kilinochchi, Mullaitivu, Vavuniya, Anuradhapura and Trincomalee districts; and up to 75 mm in most parts of the island.
MJO based OLR predictions:

For the next 15 days: 

MJO shall enhance the rainfall in Sri Lanka.

Ocean State (Text Courtesy IRI)

Pacific sea state: October 19, 2019
SSTs in the east-central Pacific were near thresholds of weak El Niño levels during October and early November. However, patterns in most atmospheric variables generally maintained neutral conditions. Oceanic warming is attributed to intraseasonal variability, and the overall diagnosis indicates ENSO-neutral conditions. Most model forecasts favor ENSO-neutral through winter and spring, with slightly higher chances for El Niño than La Niña. The official CPC/IRI outlook is consistent with these model forecasts.

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