Highlights
• The NOAA weekly rainfall forecast predicts up to 100 mm of total rainfall in Galle and Matara districts during 28 May - 2 June.
• Between
20- 26 May: up to 150 mm of rainfall was recorded in Colombo, Kalutara and
Ratnapura districts on 26th
• From 12 May -
18 May: up to 18 km/h, northwesterly winds were experienced by the southern
regions of the island.
• From
20 - 26 May: up to 18 km/h, northwesterly
winds were experienced by the northern regions of the island.
• 1
0C above-average sea surface temperature was observed in the seas around Sri Lanka.
Monitoring
Rainfall
Weekly Monitoring:
Date
Rainfall
20th May
Up to 15 mm in Kalutara and Ratnapura districts; up to 10 mm in
Colombo, Kurunegala and Nuwara Eliya districts; and up to 5 mm in Gampaha,
Kegalle, Kandy, Puttalam, Matara, Hambantota, Badulla, Monaragala and
Anuradhapura districts.
21st May
Up to 15 mm
in Kegalle, Rathnapura and Colombo districts; up to 10 mm in Kandy, Nuwara
Eliya, Matale, Gampaha, Kurunegala, Puttalam, Badulla, Kalutara, Galle and
Matara districts; and up to 5 mm in Monaragala and Ampara districts.
22nd
May
Up to 20 mm in Ratnapura, Kalutara and Galle districts, 15 mm in
Galle district, up to 10 mm in Colombo, Puttalam, Badulla and Monaragala
districts; and up to 5 mm in Kurunegala, Hambantota, Nuwara Eliya, Gampaha,
Matale, Kandy and Ampara districts.
23rd May
Up to 40 mm
in in Kilinochchi and Mullaitivu districts; up to 20 mm in Monaragala and
Galle districts; up to 15 mm in Hambantota, Ratnapura, Badulla, Kandy and
Nuwara Eliya districts; and up to 10 mm in Jaffna, Kurunegala, Kegalle,
Matale, Colombo, Kalutara, Galle and Ampara districts.
24th
May
Up to 50 mm in Monaragala district, up to 40 mm in Ratnapura,
Kegalle, Colombo and Galle districts; up to 30 mm in Mannar, Vavuniya,
Trincomalee, Polonnaruwa, Gampaha, Kalutara, Badulla and Hambantota
districts; up to 20 mm in Galle district; and up to 15 mm in Kurunegala,
Anuradhapura, Kandy, Mullaitivu and Mullaitivu districts.
25th
May
Up to 70 mm
in Vavuniya and Mullaitivu districts; up to 40 mm in Kilinochchi districts;
up to 30 mm in Monaragala, Hambantota, Ampara, Badulla, Anuradhapura,
Trincomalee, and Mannar districts; and up to 20 mm in Ratnapura, Galle,
Nuwara Eliya and Kandy districts.
26th May
Up to 150 mm
in Colombo, Ratnapura and Kalutara districts, up to 140 mm in Gampaha and Kegalle
districts; up to 90 mm in Nuwara Eliya district; up to 70 mm in Kandy,
Ampara, Monaragala and Matara districts; up to 60 mm in Galle district; up
to 50 mm in Kurunegala and Hambantota districts; and up to 30 mm in Badulla
and Puttalam districts.
Total Rainfall for the Past Week:
The RFE 2.0 tool shows total up to 150-200 mm in Ratnapura, Kegalle, Gampaha and Colombo districts; up to 100-150 mm in Kalutara and Nuwara Eliya districts; 75-100 mm in Galle, Matara and Hambantota districts; up to 50-75 mm in Badulla, Monaragala, Kandy, Kurunegala, Ampara and Mullaitivu districts; and up to 25-50 mm in Kilinochchi, Vavuniya, Polonnaruwa, Puttalam and Matale districts.
Above-average rainfall up to 100-200 mm in Ratnapura, Kegalle, Gampaha and Colombo and Kalutara districts; up to 50-100 mm in Mullaitivu and Nuwara Eliya districts; up to 25-50 mm in Kilinochchi, Vavuniya, Badulla, Monaragala, Ampara, Hambantota, Galle, Matara, Kandy and Kurunegala districts; and up to 10-25 mm in Polonnaruwa, Matale, Trincomalee and Puttalam districts.
Monthly Monitoring:
During April – Above average rainfall conditions up to 360 mm were experienced by Ratnapura, Badulla and Monaragala districts; up to 240 mm in Anuradhapura, Kegalle, Kandy and Matara districts; and up to 120 mm in Vavuniya, Matara, Nuwara Eliya, Colombo, Kalutara, Galle and Hambantota. Below-average rainfall conditions up to 240 mm were experienced by Jaffna, Kilinochchi, Mullaitivu and Gampaha districts; and up to 120 mm in Badulla, Polonnaruwa and Trincomalee districts. The CPC Unified Precipitation Analysis tool shows up to 750 mm of total rainfall in Kegalle, Ratnapura and Monaragala districts; and up to 500 mm in Anuradhapura, Kurunegala, Matale, Kandy, Nuwara Eliya, Colombo, Kalutara, Colombo, Galle and Matara districts.
Weekly Monitoring:
Date
|
Rainfall
|
20th May
|
Up to 15 mm in Kalutara and Ratnapura districts; up to 10 mm in
Colombo, Kurunegala and Nuwara Eliya districts; and up to 5 mm in Gampaha,
Kegalle, Kandy, Puttalam, Matara, Hambantota, Badulla, Monaragala and
Anuradhapura districts.
|
21st May
|
Up to 15 mm
in Kegalle, Rathnapura and Colombo districts; up to 10 mm in Kandy, Nuwara
Eliya, Matale, Gampaha, Kurunegala, Puttalam, Badulla, Kalutara, Galle and
Matara districts; and up to 5 mm in Monaragala and Ampara districts.
|
22nd
May
|
Up to 20 mm in Ratnapura, Kalutara and Galle districts, 15 mm in
Galle district, up to 10 mm in Colombo, Puttalam, Badulla and Monaragala
districts; and up to 5 mm in Kurunegala, Hambantota, Nuwara Eliya, Gampaha,
Matale, Kandy and Ampara districts.
|
23rd May
|
Up to 40 mm
in in Kilinochchi and Mullaitivu districts; up to 20 mm in Monaragala and
Galle districts; up to 15 mm in Hambantota, Ratnapura, Badulla, Kandy and
Nuwara Eliya districts; and up to 10 mm in Jaffna, Kurunegala, Kegalle,
Matale, Colombo, Kalutara, Galle and Ampara districts.
|
24th
May
|
Up to 50 mm in Monaragala district, up to 40 mm in Ratnapura,
Kegalle, Colombo and Galle districts; up to 30 mm in Mannar, Vavuniya,
Trincomalee, Polonnaruwa, Gampaha, Kalutara, Badulla and Hambantota
districts; up to 20 mm in Galle district; and up to 15 mm in Kurunegala,
Anuradhapura, Kandy, Mullaitivu and Mullaitivu districts.
|
25th
May
|
Up to 70 mm
in Vavuniya and Mullaitivu districts; up to 40 mm in Kilinochchi districts;
up to 30 mm in Monaragala, Hambantota, Ampara, Badulla, Anuradhapura,
Trincomalee, and Mannar districts; and up to 20 mm in Ratnapura, Galle,
Nuwara Eliya and Kandy districts.
|
26th May
|
Up to 150 mm
in Colombo, Ratnapura and Kalutara districts, up to 140 mm in Gampaha and Kegalle
districts; up to 90 mm in Nuwara Eliya district; up to 70 mm in Kandy,
Ampara, Monaragala and Matara districts; up to 60 mm in Galle district; up
to 50 mm in Kurunegala and Hambantota districts; and up to 30 mm in Badulla
and Puttalam districts.
|
Total Rainfall for the Past Week:
The RFE 2.0 tool shows total up to 150-200 mm in Ratnapura, Kegalle, Gampaha and Colombo districts; up to 100-150 mm in Kalutara and Nuwara Eliya districts; 75-100 mm in Galle, Matara and Hambantota districts; up to 50-75 mm in Badulla, Monaragala, Kandy, Kurunegala, Ampara and Mullaitivu districts; and up to 25-50 mm in Kilinochchi, Vavuniya, Polonnaruwa, Puttalam and Matale districts.
Above-average rainfall up to 100-200 mm in Ratnapura, Kegalle, Gampaha and Colombo and Kalutara districts; up to 50-100 mm in Mullaitivu and Nuwara Eliya districts; up to 25-50 mm in Kilinochchi, Vavuniya, Badulla, Monaragala, Ampara, Hambantota, Galle, Matara, Kandy and Kurunegala districts; and up to 10-25 mm in Polonnaruwa, Matale, Trincomalee and Puttalam districts.
During April – Above average rainfall conditions up to 360 mm were experienced by Ratnapura, Badulla and Monaragala districts; up to 240 mm in Anuradhapura, Kegalle, Kandy and Matara districts; and up to 120 mm in Vavuniya, Matara, Nuwara Eliya, Colombo, Kalutara, Galle and Hambantota. Below-average rainfall conditions up to 240 mm were experienced by Jaffna, Kilinochchi, Mullaitivu and Gampaha districts; and up to 120 mm in Badulla, Polonnaruwa and Trincomalee districts. The CPC Unified Precipitation Analysis tool shows up to 750 mm of total rainfall in Kegalle, Ratnapura and Monaragala districts; and up to 500 mm in Anuradhapura, Kurunegala, Matale, Kandy, Nuwara Eliya, Colombo, Kalutara, Colombo, Galle and Matara districts.
Predictions
Rainfall
NOAA NCEP models:
From 28th May – 3rd June: Total rainfall up to 105 mm in Ratnapura, Kegalle and Colombo districts; up to 95 mm in Kalutara and Gampaha districts; up to 85 mm in Galle and Nuwara Eliya and Badulla districts; up to 75 mm in Kandy district, up to 65 mm in Kurunegala and Matale districts; and up to 55 mm in Hambantota, Monaragala, Anuradhapura and Puttalam districts.
From 4th – 10th June: Total rainfall up to 105 mm in Ratnapura and Kegalle and Colombo districts; up to 95 mm in Kalutara district; up to 85 mm in Gampaha and Nuwara Eliya and Galle districts; up to 75 mm in Kandy and Badulla districts; up to 65 mm in Kurunegala and Matale districts; and up to 55 mm in Anuradhapura, Polonnaruwa, Vavuniya, Mullaitivu, Mannar, Monaragala and Hambantota districts.
From 28th May – 2nd June: Total rainfall up to 100 mm in Galle and Matara districts; up to 75 mm in Kalutara, Rathnapura and Hambantota districts; up to 50 mm in Colombo, Gampaha, Kegalle, Kandy, Matale, Nuwara Eliya, Badulla, Monaragala, Ampara, Batticaloa, Polonnaruwa and Trincomalee and up to 25 mm in the other parts of the island.
MJO based OLR predictions:
For the next 15 days:
MJO shall suppress the rainfall in the next 15 days and shall enhance in the following 5 days.
Ocean State (Text Courtesy IRI)
Pacific sea state: May 20, 2020
SSTs in the east-central Pacific were neutral, but above average during mid-May, and patterns in atmospheric variables are split between neutral and weak El NiƱo conditions. Most model forecasts favor warm neutral SST conditions continuing into summer, becoming below-average but not necessarily into La Nina territory by fall. The official CPC/IRI outlook is consistent with these model forecasts, calling for continuation of ENSO-neutral.
Pacific sea state: May 20, 2020
SSTs in the east-central Pacific were neutral, but above average during mid-May, and patterns in atmospheric variables are split between neutral and weak El NiƱo conditions. Most model forecasts favor warm neutral SST conditions continuing into summer, becoming below-average but not necessarily into La Nina territory by fall. The official CPC/IRI outlook is consistent with these model forecasts, calling for continuation of ENSO-neutral.
Indian Ocean State
1 0C above-average sea surface temperature was observed in the seas around Sri Lanka.
1 0C above-average sea surface temperature was observed in the seas around Sri Lanka.