Menu Close

Weekly Hydro-meteorological Report, 29, August 2019

                                                      Highlights                                

                                 
• The IRI weekly rainfall forecast predicts up to 75 mm of total rainfall in Colombo, Kalutara, Ratnapura, Matara and Galle districts during 28 Aug – 2 Sep. 
 Between 21 – 26 Aug: up to 90 mm of rainfalls were recorded in Gampaha and Kegalle districts on the 21st. 
 From 20 – 26 Aug: 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 seas around Sri Lanka. 



Monitoring

Rainfall

Weekly Monitoring:  On August 21st, Gampaha and Kegalle districts received up to 90 mm of rainfall; Kurunegala, Colombo, Kalutara, Ratnapura and Nuwara Eliya districts up to 50 mm; Jaffna, Kilinochchi and Matara districts up to 30 mm; and Puttalam, Galle and Hambantota districts up to 20 mm.  On the 22nd, Anuradhapura, Puttalam, Kurunegala, Colombo, Ratnapura and Kalutara districts received up to 30 mm of rainfall; and Matale, Kegalle, Gampaha, Nuwara Eliya, Galle, Matara and Hambantota districts up to 20 mm. On the 23rd, Kalutara and Galle districts received up to 50 mm of rainfall; Ratnapura, Matara and Hambantota districts up to 30 mm; and Kurunegala, Gampaha, Colombo, Kegalle, and Monaragala districts up to 20 mm. On the 24th, Colombo, Kalutara and Ratnapura district received up to 30 mm of rainfall; and Gampaha, Kegalle and Galle districts up to 20 mm. On the 25th, Kalutara, Colombo, Gampaha, Kegalle, Ratnapura and Nuwara Eliya districts received up to 50 mm of rainfall; Galle district up to 30 mm; and Puttalam, Kurunegala, Badulla, Ampara and Matara districts up to 20 mm. On the 26th, Matale district received up to 30 mm of rainfall; and Puttalam, Kurunegala and Ampara districts up to 20 mm.

Total Rainfall for the Past Week:  The RFE 2.0 tool shows total up to 100-150 mm in Gampaha, Colombo, Kalutara, Galle, Ratnapura and Kegalle districts; up to 75-100 mm in Kurunegala. Nuwara Eliya, Matara and Hambantota districts; and up to 50-75 mm Puttalam district. Above-average rainfall up to 100-200 mm in Gampaha, Colombo, Kalutara and Ratnapura districts; up to 50-100 mm in Kurunegala, Kegalle, Galle, Matara, Nuwara Eliya and Hambantota districts; and up to 25-50 mm in Jaffna, Puttalam, Matale and southern regions of Anuradhapura, Badulla and Monaragala districts.  Below-average rainfall up to 25-50 mm in Vavuniya district; and up to 10-25 mm in Mannar, Mullaitivu, Trincomalee, Ampara, Kandy and northern regions of Anuradhapura, Badulla and Monaragala districts. 

Monthly Monitoring: During July – Above average rainfall conditions up to 60 mm were experienced by Puttalam, Kurunegala. Kandy, Nuwara Eliya, Badulla, Monaragala, Ampara and Hambantota districts. Below-average rainfall conditions, up to 60 mm were experienced by Jaffna, Kilinochchi, Mullaitivu, Mannar, Vavuniya, Matale, Gampaha, Colombo, Kalutara, Galle and Batticaloa districts. The CPC Unified Precipitation Analysis tool shows up to 200 mm of total rainfall in Nuwara Eliya, Badulla and Ratnapura districts; up to 150 mm in Kalutara, Galle, Matara, Kegalle, Kandy and Monaragala districts; up to 100 mm in Puttalam, Kurunegala, Matale and Ampara districts; and up to 75 mm in Gampaha and Trincomalee districts. 


Predictions


Rainfall

14-day prediction: 

NOAA NCEP models: 

From 28th Aug – 3rd Sep: Total rainfall up to 65 mm on Ratnapura and Galle districts; up to 45-55 mm in Colombo, Kegalle, Matara and Hambantota districts; and up to 35-45 mm in Gampaha, Puttalam, Kurunegala, Nuwara Eliya, Badulla and Monaragala districts.

From 4th – 10th Sep: Total rainfall up to 75 mm Ratnapura and Galle districts; and up to 45-55 mm in Gampaha, Kegalle, Nuwara Eliya, Hambantota, Badulla and Monaragala districts. 


IMD NCMWRF Forecast:

30th Aug: Not Available

31st Aug: Not Available 


IRI Model Forecast: 

From 28th Aug – 2nd Sep: Total rainfall up to 75 mm is expected in Colombo, Kalutara, Ratnapura, Matara and Galle districts; and up to 25 mm in most parts of the island. 


MJO based OLR predictions:

For the next 15 days: 
MJO shall not have an impact on the rainfall in Sri Lanka.  

Ocean State (Text Courtesy IRI)
Pacific sea state: August 19, 2019
The weak El Niño of 2018-19 has ended, as SSTs in the east-central Pacific cooled to ENSO-neutral levels during July. Patterns in most atmospheric variables also are showing ENSO-neutral conditions. Collective model forecasts favor ENSO-neutral through autumn and winter, but with higher chances for El Niño than La Niña. The official CPC/IRI outlook, no longer carrying an El Niño advisory, generally agrees with the model forecasts through winter.
Indian Ocean State

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

%d bloggers like this: