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Friday, May 31, 2019

Weekly Hydro-meteorological Report, 30, May 2019

Highlights
  • The IRI weekly rainfall forecast predicts up to 50 mm of total rainfall in western and central parts of the island during 29 May – 3 Jun.
  • Between 21 - 27 May: up to 60 mm of rainfall was recorded in Colombo district on the 23rd.
  • From 21 - 27 May: up to 36 km/h, westerly winds were experienced by the entire island.
  • 0.5 0C below average sea surface temperature was observed in the southern seas around Sri Lanka.



Monitoring

Weekly Monitoring:On May 21st, Jaffna and Kilinochchi districts received up to 10 mm of rainfall. On the 22nd, Nuwara Eliya district received up to 20 mm of rainfall; and Galle and Hambantota districts up to 10 mm. On the 23rd, Colombo district received up to 60 mm of rainfall; Gampaha and Kalutara district up to 50 mm; Trincomalee, Polonnaruwa, Kegalle, Ratnapura and Galle districts up to 30 mm; and Puttalam, Anuradhapura, Kandy and Matara districts up to 20 mm. On the 24th, Colombo district received up to 30 mm of rainfall; and Gampaha, Kegalle, Ratnapura, Kalutara, Galle, Badulla and Monaragala districts up to 20 mm. On the 25th, Ampara, Galle and Matara districts received up to 20 mm of rainfall. On the 26th, Puttalam district received up to 20 mm of rainfall; and Colombo district up to 10 mm. No significant rainfalls were recorded in any part of the island on the 27th.

Total Rainfall for the Past Week: TThe RFE 2.0 tool shows total up to 75-100 mm in Colombo district; up to 50-75 mm in Gampaha and Kalutara districts; up to 25-50 mm in Kegalle, Ratnapura, Galle, Matara, Trincoalee and Badulla districts; and 10-25 mm in Polonnaruwa, Matale, Kandy, Nuwara Eliya, Monaragala, Puttalam, Kurunegala and Hambantota districts. Above average rainfall up to 25-50 mm is shown for Trincomalee, Polonnaruwa and Colombo districts. Below average rainfall up to 25-50 mm is shown for Kurunegala, Kandy, Nuwara Eliya, Ratnapura, Galle, Badulla, Monaragala and Ampara districts; and up to 10-25 mm in Matale, Puttalam, Kegalle, Matara and Hambantota districts.

Monthly Monitoring: During April – Above average rainfall conditions up to 60 mm were experienced in western regions of Kurunegala district and central regions of Anuradhapura district. Below average rainfall conditions up to 240 mm were experienced by Matale, Kandy, Nuwara Eliya, Kegalle, Colombo, Kalutara, Galle, Matara, Ratnapura, Hambantota, Badulla and Monaragala districts; and up to 180 mm in rest of the island. The CPC Unified Precipitation Analysis tool shows up to 500 mm of total rainfall in Gampaha district; up to 300 mm in Puttalam, Kurunegala, Anuradhapura, Kegalle, Ratnapura, Colombo, Kalutara and Galle districts; up to 200 mm in Matale, Kandy, Nuwara Eliya and Matara districts; and up to 100 mm in Mannar, Vavuniya, Polonnaruwa, Badulla, Monaragala, Batticaloa, Ampara and Hambantota districts.

Predictions

Rainfall

14-day prediction: 
NOAA NCEP models: 
From 29th May – 4th Jun: Total rainfall up to 55 mm Ratnapura and Matara districts; up to 35-45 mm in Hambantota district; and up to 25-35 mm in Colombo and Gampaha districts.

From 5th – 11th Jun: Total rainfall up to 55 mm in Ratnapura, Galle districts; up to 35-45 mm in Ratnapura and Matara districts; up to 25-35 mm in Colombo, Gampaha, Kegalle and Hambantota districts.

IMD NCMWRF Forecast: 
31st May: Not Available
1st Jun: Not Available

IRI Model Forecast: 
From 29th May – 3rd Jun: Total rainfall up to 50 mm is expected in Nuwara Eliya, Kandy, Badulla, Kegalle, Ratnapura, Gampaha, Colombo, Kalutara, Galle and Matara districts. MJO based OLR predictions For the next 15 days: MJO shall suppress the rainfall in Sri Lanka in the next 5 days and shall enhance in the following 10 days.


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: May 20, 2019
SSTs in the tropical Pacific maintained a weak El Niño level during April and early May, while temperature anomalies of subsurface waters decreased markedly to just slightly above average. Some patterns in the atmosphere show weak El Niño conditions. Collective model forecasts show a continuation of at least weak El Niño-level SSTs lasting through 2019. The official CPC/IRI outlook, with an El Niño advisory, calls for an approximate 70% chance of El Niño continuing during Jun-Aug, decreasing to 55-60% for Sep-Nov.

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

Friday, May 24, 2019

Weekly Hydro-meteorological Report, 23, May 2019

Highlights
  • The IRI weekly rainfall forecast predicts up to 75 mm of total rainfall in Kandy, Badulla and Nuwara Eliya districts during 22 – 27 May.
  • Between 14 - 21 May: up to 50 mm of rainfall was recorded in Monaragala district on the 16th and 17th.
  • From 14 - 20 May: up to 36 km/h, westerly winds were experienced by the central and southern regions of the island.
  • Average sea surface temperature was observed in the seas around Sri Lanka.



Monitoring

Weekly Monitoring: On May 14th, Kalutara, Galle and Matara districts received up to 10 mm of rainfall. On the 15th, Polonnaruwa, Ampara and Badulla districts received up to 20 mm of rainfall; and Galle and Matara districts up to 10 mm. On the 16th, Badulla, Monaragala and Ampara districts received up to 50 mm of rainfall; Galle, Kandy and Matale districts up to 20 mm; and Kalutara and Polonnaruwa districts up to 10 mm. On the 17th, Badulla, Monaragala and Ampara districts received up to 10 mm of rainfall. On the 18th, Badulla, Monaragala, Ratnapura, Polonnaruwa, Hambantota and Matara districts received up to 20 mm of rainfall; and Kegalle and Ampara districts up to 10 mm. On the 19th, Monaragala district received up to 50 mm of rainfall; Kandy and Colombo districts up to 20 mm; and Kegalle, Ratnapura and Nuwara Eliya districts up to 10 mm. On the 20th, Vavuniya district received up to 30 mm of rainfall; Mullaitivu and Anuradhapura districts up to 20 mm; and Kalutara and Badulla districts up to 10 mm. On the 21st, Jaffna and Kilinochchi districts received up to 10 mm of rainfall

Total Rainfall for the Past Week: The RFE 2.0 tool shows total up to 50-75 mm in Badulla and Monaragala districts; up to 25-50 mm in Ampara district; and 10-25 mm in Vavuniya, Anuradhapura, Polonnaruwa, Matale, Kandy, Nuwara Eliya, Kegalle, Gamapaha, Colombo, Kalutara, Ratnapura, Galle and Matara districts. Above average rainfall up to 25-50 mm is shown for Northern regions of Monaragala district; and up to 10-250 mm in Badulla and Vavuniya districts. Below average rainfall up to 50-100 mm is shown for Gampaha, Colombo, Kalutara and Ratnapura districts; up to 25-50 mm in Puttalam, Kurunegala, Kegalle, Nuwara Eliya, Galle, Matara and Hambantota districts; and up to 10-25 mm in Matale, Kandy and Southern regions of Monaragala districts

Predictions

Rainfall

14-day prediction: 
NOAA NCEP models: 
From 22nd – 28th May: Total rainfall up to 55 mm Matara and Galle districts; up to 35-45 mm in Ratnapura and Hambantota districts; and up to 25-35 mm in Colombo and Monaragala districts. From 29th May – 4th Jun: Total rainfall up to 75 mm in Ratnapura, Galle and Matara districts; up to 55-65 mm in Kalutara district; up to 35-45 mm in Gampaha, Kegalle and Monaragala districts; up to 25-35 mm in Jaffna, Kilinochchi, Vavuniya and Mullaitivu districts; and up to 5-15 mm most parts of the island.

IMD NCMWRF Forecast: 
24th May: Not Available
25th May: Not Available

IRI Model Forecast: 
From 22nd – 27th May: 
Total rainfall up to 75 mm is expected in Nuwara Eliya, Kandy and Badulla districts; and up to 50 mm in Polonnaruwa, Matale, Kegalle, Ratnapura, Kalutara, Galle, Matara, Batticaloa, Monaragala and Ampara districts. MJO based OLR predictions For the next 15 days: MJO shall suppress the rainfall in Sri Lanka in the next 5 days and shall enhance in the following 10 days.


MJO based OLR predictions:
For the next 15 days:
MJO shall suppress the rainfall in Sri Lanka in the next 5 days and shall enhance in the following 10 days.

Ocean State (Text Courtesy IRI)
Pacific sea state: May 20, 2018
SSTs in the tropical Pacific maintained a weak El Niño level during April and early May, while temperature anomalies of subsurface waters decreased markedly to just slightly above average. Some patterns in the atmosphere show weak El Niño conditions. Collective model forecasts show a continuation of at least weak El Niño-level SSTs lasting through 2019. The official CPC/IRI outlook, with an El Niño advisory, calls for an approximate 70% chance of El Niño continuing during Jun-Aug, decreasing to 55-60% for Sep-Nov.
Indian Ocean State
Average sea surface temperature was observed in the seas around Sri Lanka.

Thursday, May 16, 2019

Weekly Hydro-meteorological Report, 16, May 2019

Highlights:

  •   The IRI weekly rainfall forecast predicts up to 75 mm of total rainfall in Badulla and Nuwara Eliya districts during 15 – 20 May.
  •   Between 7 - 13 May: up to 90 mm of rainfall was recorded in Trincomalee district on the 12th.
  •  From 7 - 13 May: up to 36 km/h, westerly winds were experienced by the central and southern regions of the island.
  •   Average sea surface temperature was observed in the seas around Sri Lanka.
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Thursday, May 9, 2019

Weekly Hydro-meteorological Report, 9, May 2019

Highlights:

  •   The IRI weekly rainfall forecast predicts up to 25 mm of total rainfall in the entire island during 8 – 13 May.
  •   Between 30 Apr - 6 May: up to 90 mm of rainfall was recorded in Galle and Matara districts on the 3rd.
  •  From 30 Apr - 6 May: up to 36 km/h, westerly winds were experienced by the entire island.
  •   0.5 0C above average sea surface temperature was observed in the eastern seas around Sri Lanka.
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Thursday, May 2, 2019

Weekly Hydro-meteorological Report, 2, May 2019

Highlights:

  •   The IRI weekly rainfall forecast predicts up to 75 mm of total rainfall in Galle district during 1 – 6 May.
  •   Between 23 – 29 Apr: up to 70 mm of rainfall was recorded in Ratnapura district on the 29th.
  •  From 23 – 29 Apr: up to 12 km/h, northeasterly winds were experienced by the entire island.
  •   1 0C above average sea surface temperature was observed in the seas around Sri Lanka.
Download Full Report