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Biyagama
Biyagama · Gampaha
Not listedFri 9 Oct
Today’s warning doesn’t mention Biyagama
We don’t know about closures or damage: call 119 before you set off.
NBRI, issued Fri 9 Oct, 16:00 · valid to Sat 10 Oct, 16:00lankawatch.org
Rain hereNot unusual for hereLast 3 days · Satellite estimateNearest rain gaugeNagalagam StreetNo rain report · 11 km awayMet advisoryAdvisory for Severe LightningAmber, as issuedRiversNagalagam Street: Below Alertfalling
Next update usually tomorrow by 17:45.
Rain here
×Rain here
Last 3 days: Not unusual · Amber · Advisory for Severe Lightning
- Rain over the last 7 days has not been unusual for the divisions on this route.
- Compared with each division's own satellite record since 2000. This is not a warning and does not replace NBRI's levels. Satellites can miss heavy local downpours, so it never means a road is safe. Satellite data up to 9 Oct, 15:30.
Weather forecast (Department of Meteorology) · Amber · Advisory for Severe Lightning
- Amber · Advisory for Severe Lightning. For Western, Sabaragamuwa, Central, Uva, North-western, Southern provinces and Anuradhapura, Mannar districts.. Thundershowers accompanied with severe lightning are likely to occur at several places in Western, Sabaragamuwa, Central, Uva, North-western and Southern provinces and Anuradhapura and Mannar districts. There may be temporary localized strong winds during thundershowers. General public is kindly requested to take adequate precautions to minimize damages caused by lightning activity. Issued 9 Oct, 11:00 · Valid until 10 Oct, 01:00.
- Forecast issued 9 Oct, 14:00
- Showers or thundershowers will occur in the most part of the island after 1.00 p.m.
- Covers Gampaha on this road: Fairly heavy falls above 75 mm are likely at some places in Western, Sabaragamuwa, Central, Uva, North-Western and Southern provinces.
- The general public is kindly requested to take adequate precautions to minimize damage caused by temporary localized strong winds and lightning during thundershowers.
- Covers Gampaha on this road: Misty conditions can be expected at some places in Western, Sabaragamuwa, Central and Uva provinces during the early hours of the morning.
- A forecast never lowers or replaces the NBRI landslide warning above.
- Forecast and advisories by the Department of Meteorology, Sri Lanka, as issued. LankaWatch is not an official service.
Rain outlook (computer model) · Next day: Chance of a rare wet day
- Next day: a chance of a wet day of the kind that comes about 1–2 days a month in Biyagama (the wettest 5% of days there; several times the usual chance). (10 Oct, 05:30 to 11 Oct, 05:30)
- Next 3 days: a chance of a wet day of the kind that comes about 1–2 days a month in Biyagama (the wettest 5% of days there; several times the usual chance). (10 Oct, 05:30 to 13 Oct, 05:30)
- "Not signalled" never means dry or safe. This is a computer model, not a warning, and it never changes NBRI's levels. Like the satellite, it reads hill-country rain low and can miss heavy local downpours.
- ECMWF ensemble forecast (open data, CC BY 4.0), run 9 Oct, 05:30, compared with each division's own satellite record.
None of these changes NBRI’s level.
Weather forecast (Met Dept)
×- Amber · Advisory for Severe Lightning. For Western, Sabaragamuwa, Central, Uva, North-western, Southern provinces and Anuradhapura, Mannar districts.. Thundershowers accompanied with severe lightning are likely to occur at several places in Western, Sabaragamuwa, Central, Uva, North-western and Southern provinces and Anuradhapura and Mannar districts. There may be temporary localized strong winds during thundershowers. General public is kindly requested to take adequate precautions to minimize damages caused by lightning activity. Issued 9 Oct, 11:00 · Valid until 10 Oct, 01:00.
- Forecast issued 9 Oct, 14:00
- Showers or thundershowers will occur in the most part of the island after 1.00 p.m.
- Covers Gampaha on this road: Fairly heavy falls above 75 mm are likely at some places in Western, Sabaragamuwa, Central, Uva, North-Western and Southern provinces.
- The general public is kindly requested to take adequate precautions to minimize damage caused by temporary localized strong winds and lightning during thundershowers.
- Covers Gampaha on this road: Misty conditions can be expected at some places in Western, Sabaragamuwa, Central and Uva provinces during the early hours of the morning.
- A forecast never lowers or replaces the NBRI landslide warning above.
- Forecast and advisories by the Department of Meteorology, Sri Lanka, as issued. LankaWatch is not an official service.
Rivers and catchments here
×1 named river here · 1 basin
River basins this division lies in
- Kelani Ganga basin
Satellite rain over these basins
- Kelani Ganga basin · Last 24 hours: Unusual here (3 days a month)
A whole-basin satellite average against that basin’s own record since 2000, not the area upstream of any one point. Satellites under-read hill rain. Not a warning.
Named rivers through this division
- Kelani Ganga · about 5 km inside
Irrigation Department gauges on these rivers
- Nagalagam Street, an Irrigation Department gauge 8.1 km downstream (2,256 km² upstream · rain over that area, Last 24 hours: Unusual here (3 days a month)): no report.
River level 1.1 ft · Below Alert · falling over about 3 hours (Department’s thresholds: Alert 4, minor flood 5, major flood 7 ft) - Hanwella, an Irrigation Department gauge 11.4 km upstream (1,820 km² upstream · rain over that area, Last 24 hours: Unusual here (3 days a month)): 4.6 mm in the 24 hours to 9 Oct, 08:30 (Light); 25.2 mm in the 3 hours to 9 Oct, 20:02.
River level 3.41 m · Below Alert · rising over about 3 hours (Department’s thresholds: Alert 6.5, minor flood 7.5, major flood 9.5 m)
Rivers and basins come from our own map of Sri Lanka’s river network. Flow direction, where shown, is worked out from the height of the land. This is orientation only, not a flood warning.
The area draining to a crossing is worked out from a terrain model (about 90 m cells) and is approximate. The rain over it is the satellite average for that same area, against its own record since 2000. Areas under about 150 km² are smaller than the satellite can see, so they show no rain.
River levels are the Irrigation Department’s own readings at its gauge, against its own thresholds. This is not a flood warning: flood warnings come from the Irrigation Department and DMC.