Awareness

Hazards for which MMS issues Alert

Meteorological

Earthquake & Tsunami

Minor

Alert Level 1, White

Hazard

Heavy Rain

50 mm in 1hr or 80 mm in 6 hrs

Thunderstorms

Continuous TS reported for past 4 hrs and evidence from satellite foto/Radar.

Wind and Seas

19-24 mph(past 3 hrs) or 22 – 27 mph(past 1hr), or forecast to meet this condition

Squalls

(Frequent Gusts)

50 mph

Tropical Cyclone

RSMC declare TC center in the box within lat’ S5-N12, lon’ E66-E81

Earthquake

Magnitude >6 within 400km of Maldives EEZ. Or mag>7 in Indian Ocean within 4000km of Maldives EEZ.

Tsunami

Magnitude >8 in Indian Ocean within 4000km of Maldives EEZ. Or confirmation of Indian ocean wide Tsunami of low impact to Maldives.

Moderate

Alert Level 2, Yellow

Hazard

Heavy Rain

70 mm in 1hr or 100 mm in 6 hrs

Flood

(Highly depend on Island)

Based on evidence and situation

Thunderstorms

Continuous TS reported for past 8 hrs and evidence from satellite foto/Radar.

Wind and Seas

25-30 mph(past 3 hrs) or 28 – 35 mph(past 1hr), ), or forecast to meet this condition

Squalls

(Frequent Gusts)

55 mph

Swell and Tidal Waves

(Observed or Forecast)

Observed or forecast ( inundation level 1)

Tropical Cyclone

TC track towards Maldives and expect to cross Maldives atolls in next 24hr

Earthquake

Magnitude >7 within 400km of Maldives EEZ. Or mag>8 in Indian Ocean within 4000km of Maldives EEZ.

Tsunami

Magnitude>9 in Indian Ocean within 4000km of Maldives EEZ. Or confirmation of Indian ocean wide Tsunami of moderate impact to Maldives.

Severe

Alert Level 3, Orange

Hazard

Heavy Rain

90 mm in 1hr or 120 mm in 6 hrs

Flood

(Highly depend on Island)

Based on evidence and situation

Wind and Seas

34-40 mph(past 3 hrs) or 36 – 42 mph(past 1hr), ), or forecast to meet this condition

Squalls

(Frequent Gusts)

63 mph

Swell and Tidal Waves

(Observed or Forecast)

Observed or forecast ( inundation level 2)

Tropical Cyclone

TC track towards Maldives and expect to cross Maldives atolls in next 12hr

Earthquake

Magnitude > 8 within 400km of Maldives EEZ. Or mag>9 in Indian Ocean within 4000km of Maldives EEZ.

Tsunami

Confirmation of Indian ocean wide Tsunami of high impact to Maldives.

Extreme

Alert Level 4, Red

Hazard

Heavy Rain

180 mm in 6 hours

Flood

(Highly depend on Island)

Based on evidence and situation

Wind and Seas

>40 mph(past 3 hrs) or >42 mph(past 1hr), ), or forecast to meet this condition

Squalls

(Frequent Gusts)

70 mph

Swell and Tidal Waves

(Observed or Forecast)

Observed or forecast ( inundation level 3)

Tropical Cyclone

TC track towards Maldives and expect to cross Maldives atolls in next 6hrs

Earthquake

Magnitude >9 within 400km of Maldives EEZ.

Tsunami

Confirmation of Indian ocean wide Tsunami of extreme impact to Maldives.

Frequently asked questions

Some of the Natural Hazards in the Maldives

Heavy rain

The Maldives experiences prolonged rain and showers mainly during the south-west monsoon. However heavy sowers also occur in southern atolls during North-east monsoon as well.

Flood

Some islands are more prone to flooding due to topographical features and soil condition. The main cause of flooding are due to heavy rain and swell surge. Such flooding causes damage to household items and agricultural crops.

Strong wind

Onset of South-west monsoon is normally marked with strong Southwest to Northwesterly winds which last for few days. Strong winds also prevail during North east monsoon mostly in central and northern atolls of Maldives.  These strong winds caused uprooting of trees, blowing off the house roofs. In addition, rough seas cause interruption of ferry service between islands and difficulty to the fisherman.

Thunder and Lightning

Due to its geographic location, thunder storms occur throughout the year. Thunderstorms are observed to be more frequent during the month of April. In the south-west monsoon thunder is experienced with rain showers. Thunder storms causes lightning strikes, damaging electrical and electronic items. It also destroys tall trees in the proximity of its strike.

Tidal Waves, Swell Surge

The tidal waves or swell surge is locally referred to as “Udha”. They are almost annually occurring events at varying magnitude to almost in every island. Its impact is high when high swell and wind wavs coincide with the spring tide days. Frequent “Udha” contaminates ground water lens of the island and makes the soil less fertile for agricultural activities. At times in severe events, it also damages vessels at harbor and destroys house hold items as well.

Tropical Cyclone

It is rare that tropical cyclone crossing Maldives area. However, the cyclones forming over Bay of Bengal, Arabian Sea and Southern Indian Ocean causes formation of intense cloud bands and thus bring heavy rain and strong winds over the country. It also interrupts ferry service and fishing activities due to rough sea condition. Furthermore, the storm surge caused by cyclone causes swell surge to many islands.

Earthquake and Tsunami Watch

After the 2004 Indian Ocean Tsunami, the national tsunami warning center (NTWC) was established in Maldives Meteorological Service (MMS). Earthquake data were collected from the US Geological Survey (USGS) and later in 2005 their real time earthquake monitoring system, California Integrated Seismic Network (CISN) was introduced into the NTWC. In 2007, “SeiscomP3” system was added to our real time earthquake monitoring system. Geologically, Maldives is located on the Indian tectonic plate which makes Indian Ocean ring as our main area of concern. There are two main subduction zones in this ring, the plate boundaries near Sumatra, Indonesia and the Makran coast. Large magnitude earthquakes in subduction zones tend to create Tsunamis, hence these areas are given a special importance.

Seismic Network in Maldives

After the 2004 Tsunami, National Meteorological Centre started to develop its early warning system and introduced seismology in to the center. Through the German Indonesian Tsunami Early Warning System (GITEWS) project, a broadband seismometer was installed in Hdh Hanimaadhoo and Gdh Kaadedhhoo. Seismic data collected from these stations are transferred to the main hub in Jakarta, Indonesia via satellite antenna installed at the stations. The stations are solar powered and the VSAT modem is mains powered with backup battery installed. For backup communication, a (Broadband Global Area Network) BGAN is installed in each station.

SeiscomP3 System

SeiscomP3 was installed in Maldives Meteorological Service in early 2008 for the real time earthquake monitoring. The system displays real time seismic waves and is capable of automatically calculating earthquakes within a few minutes.