Highlights
• High
likelihood of fairly heavy rainfall (50 - 100 mm) is predicted for the Western,
Southern, Sabaragamuwa, North Western, Central provinces and moderate rainfall
(25 - 50 mm) is predicted for the rest during 29 May - 4 June.
• On average 8.6 mm was received in SL,
rainfall was concentrated on the western hills (22 mm) and plains (17 mm)
during 22 - 29 May. Depression 99B intensified as a severe
cyclonic storm ('Remal') and made
landfall over the Bangala/West Bengal border regions on 26 May.
• Strong winds at 850mb (1.5 km) westerly from
21 - 27 May reaching up to 30m/s due to
the cyclonic storm. Winds at 850mb are predicted north westerly
to south westerly from 30 May - 5 June reaching up to 10 m/s.
• Average
land surface temperature was 30.8ºC in
the last week with cooler anomalies from seasonal average of -1ºC to -3ºC. The temperature has dropped slightly. Sea surface temperature around Sri Lanka was
0.25 - 1.5ºC above normal.
Predictions
Rainfall
14-day prediction:NOAA NCEP models:
From 29th May - 4th June:
Total rainfall by Provinces
- 75 mm - North Western, Western, Southern, Sabaragamuwa
- 55 mm - Central
- 45 mm - North Central
- 35 mm - Uva, Northern
- 25 mm - Eastern
From 5th June - 11th June:
Total rainfall by Provinces
- 85 mm - North Western
- 75 mm - Western, Sabaragamuwa
- 65 mm - Central, Southern
- 45 mm - North Central
- 35 mm - Northern, Uva, Eastern
MJO based OLR predictions:
For the next 15 days:
Ocean State (Text Courtesy IRI)
Pacific Sea Sate: May 27, 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 east central and eastern Pacific
Ocean. La Niña may develop in
June-August 2024 (49% chance) or July-September (69% chance).
Interpretation
Monitoring
Rainfall: : During the last two weeks, there had been very heavy rainfall
over the following area: Keragala
(Ratnapura).
Daily
Average Rainfall in the Met stations for
previous week of (22nd May - 29th May) = 8.6 mm
Maximum Daily Rainfall: 48.5 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 |
4.6 |
31.9 |
26.9 |
|
Eastern hills |
1.5 |
28.4 |
21.0 |
|
Eastern plains |
0.4 |
33.4 |
26.5 |
|
Western hills |
22.3 |
25.5 |
20.9 |
|
Western plains |
17.3 |
30.7 |
25.9 |
|
Southern plains |
4.1 |
31.5 |
25.6 |
|
Region |
Average rainfall for last 8 days
(mm) |
Daily maximum rainfall for last 8
days (mm) |
Daily minimum rainfall for last 8
days (mm) |
|
All SL |
8.6 |
48.5 |
0.0 |
|
Hydro catchment |
31.1 |
147.0 |
0.0 |
Wind: Westerly winds prevailed in the sea
area and around the island last week.
Temperatures: The temperature anomalies were below normal for the Northern, North Central, North Western provinces and some parts of the Eastern, Western, and Central provinces driven by the warm SST’s.
Temperatures: The temperature anomalies were below normal for the Northern, North Central, North Western provinces and some parts of the Eastern, Western, and Central provinces driven by the warm SST’s.
Predictions
Rainfall: During the next week (29th May - 4th June),
fairly heavy rainfall (50 - 100 mm) is predicted for the Western, Southern, Sabaragamuwa,
North Western, and Central provinces and moderate rainfall (25 - 50 mm) is predicted for
the rest.
Temperatures: The temperature will
remain above normal for some parts of the Northern, Eastern, and North Central provinces
during 30th May - 5th June.
Teleconnections: MJO shall slightly enhance the
rainfall during 29th May - 2nd June, and near neutral the
rainfall during 3rd June - 12th June for Sri Lanka.
Seasonal Precipitation: The
precipitation forecast for the June-July-August, 2024 season shows a 50% or
more tendency toward above normal precipitation for the country.
