Highlights
• High
likelihood of Extreme rainfall (100 - 150 mm) is predicted for the all over the
country during 15 - 21 May.
• Only 5/6 of expected rainfall (100mm) was
received during 15 April - 14 May. Apart from
Western region, a big deficit of rainfall was observed during April.
• Winds at 850mb (1.5 km) were north
westerly from 6 - 12 May reaching up to 3 m/s. Winds at 850mb (1.5 km) are predicted north
westerly from 16 - 22 May reaching up to 15 m/s.
• Average land surface temperature was 33.0ºC in the last week with warmer anomalies of +1-3oC. Sea surface temperature around Sri Lanka was
1.0 - 2.0ºC above the seasonal normal. The temperature has dropped slightly.
Predictions
Rainfall
14-day prediction:NOAA NCEP models:
From 16th May - 22nd May:
Total rainfall by Provinces
- >135 mm - Western, Sabaragamuwa, North Western, Southern, Central, Uva, North central
- <125 mm - Northern, Eastern
From 23rd May - 29th May:
Total rainfall by Provinces
- 105 mm - Western
- 95 mm - Sabaragamuwa
- 85 mm - Central, North Western, Southern
- 65 mm - Uva
- 55 mm - North Central
- 45 mm - Northern, Eastern
MJO based OLR predictions:
For the next 15 days:
MJO
shall moderately enhance the rainfall during 16th - 20th
May and slightly enhance the rainfall during 21th - 30th May
for Sri Lanka.
Ocean State (Text Courtesy IRI)
Pacific Sea Sate: May 13, 2024
El Niño is
transitioning toward ENSO-neutral. Equatorial sea surface temperatures (SSTs)
are above average in the western and central Pacific Ocean, and below-average
SSTs are emerging in parts of the eastern Pacific Ocean. La Niña may develop in
June-August 2024 (49% chance) or July-September (69% chance)..
Indian Sea Sate
Sea
surface temperature around Sri Lanka was 1.0℃ above normal to the Western, Northern, and Southern half of the country in 23rd
- 29th April 2024
Interpretation
Monitoring
Rainfall: : During the last two weeks, there had been very heavy rainfall
over the following area: Ratmalana.
Daily Average Rainfall in the Met stations for previous week of (8th May - 15th May) = 12.0 mm
Maximum Daily Rainfall: 154.7 mm & Minimum Daily Rainfall: 0.0 mm.
|
Region |
Average rainfall for last 8 days
(mm) |
Average temperature for last 8
days (ºC) |
|
|
Maximum |
Minimum |
||
|
Northern plains |
11.5 |
34.6 |
25.6 |
|
Eastern hills |
14.2 |
28.4 |
19.7 |
|
Eastern plains |
8.0 |
34.1 |
25.4 |
|
Western hills |
14.8 |
30.3 |
20.2 |
|
Western plains |
15.0 |
33.1 |
25.5 |
|
Southern plains |
9.2 |
33.9 |
25.4 |
|
Region |
Average rainfall for last 8 days
(mm) |
Daily maximum rainfall for last 8
days (mm) |
Daily minimum rainfall for last 8
days (mm) |
|
Hydro catchment |
16.8 |
68.5 |
0.0 |
Wind: North westerly winds prevailed in the sea area and around the island last week.
Temperatures: The temperature
anomalies were above normal for the country except some parts of the Northern,
Eastern, and Western provinces driven by the warm
SST’s.
Predictions
Rainfall: During the next week (15th May - 21st May),
heavy rainfall (100 - 150mm) is predicted for the Western, Sabaragamuwa, North Western, Southern, Central, and
Uva Provinces and
fairly heavy
rainfall (50 - 100 mm) is predicted for the rest.
Temperatures: The temperature will
remain below normal for some parts of the Central, Western, North Western,
Southern, and Uva provinces during 16th - 22nd May.
Teleconnections: MJO shall moderately enhance the
rainfall during 16th - 20th May and slightly enhance the
rainfall during 21th - 30th May for Sri Lanka
Seasonal Precipitation: The
precipitation forecast for the June-July-August, 2024 season shows a 50% tendency
toward above normal precipitation for the country.
