Overall Red alert Tropical Cyclone for GITA-18
in Tonga

Impact

Tropical Cyclone GITA-18 can have a high humanitarian impact based on the maximum sustained wind speed,exposed population and vulnerability.

Meteorological source GDACS (JTWC)
Exposed countries Tonga
Exposed population 80 thousand in Category 1 or higher
Maximum wind speed 231 km/h
Maximum storm surge 0.4 m (09 Feb 14:00 UTC)
Vulnerability Medium (Tonga)

GDACS Score

GDACS alert score for Tropical Cyclones is 0.5 (GREEN Alert), 1.5 (ORANGE Alert), 2.5 (RED Alert)
For more info on GDACS alert score click here.
  Wind Storm surge Rainfall GDACS score
GDACS Current 120 km/h 0.4 m n.a. 1.5
GDACS Overall 231 km/h 0.4 m n.a. 1.5

Maximum winds, storm surge, rainfall (Current: over the next 72 h, Overall: entire TC track)

Wind

120 km/h Current

Up to 84000 people in Category 1 strength or higher (see SSHS)

Impact Timeline

Alert Date (UTC) Max Winds (km/h) Population in
Tropical Storm
Population in
Cat. 1 or higher
Countries
Orange 1 09 Feb 2018 00:00 120 390 thousand 80 thousand Tonga

Bulletin Timeline

Alert Date (UTC) Category Max winds
(km/h)
Population in
Tropical Storm
Population in
Cat.1 or higher
Location (lat, lon) Countries
GREEN
1 09 Feb 2018 00:00 Tropical storm 74 260000 people no people -13.8, -175.5 American Samoa
GREEN
1 09 Feb 2018 12:00 Tropical storm 102 260000 people 82000 people -13.8, -172.4 American Samoa
GREEN
1 10 Feb 2018 00:00 Category 1 130 250000 people no people -15.2, -169.3 Niue
GREEN
1 10 Feb 2018 12:00 Category 1 120 2100 people no people -17.8, -167.7 Niue
GREEN
1 11 Feb 2018 00:00 Tropical storm 111 100000 people no people -20.2, -168 Niue
ORANGE
1 12 Feb 2018 00:00 Category 1 120 100000 people 83000 people -21.3, -172.1 Tonga
GREEN
1 13 Feb 2018 00:00 Category 1 139 120000 people <1000 people -20.7, -176.2 Fiji
GREEN
1 14 Feb 2018 00:00 Category 1 139 no people no people -20.9, -179.8
Actual track of the current bulletin
The alert for forecast greater than 3 days is limited to Orange level.



Exposed population

Countries

Country
Tonga

Provinces

Region Province Country Population
Tonga Tonga 98000 people

Populated places

Name Region Province Country City class Population Distance
Nuku'alofa Tonga Capital 24000 people 812 km

Critical infrastructure

Airports, ports, nuclear plants and hydrodams at risk, if affected, are listed below.

Airports

Name IATA Code Elevation (m) Usage Runway type IFR Runway Length (ft) Distance
Fua'amotu International TBU 38 Civ. Paved Yes 8700 825 km
Ono-I-Lau ONU unknown 0 831 km
Eua Kaufana EUA unknown 0 841 km

Ports

Name LOCODE Country Distance
Nuku'alofa TOTBU Tonga 812 km
Eua Island Tonga 840 km

Rainfall

Rainfall accumulation of the past 24h, as detected by the Global Precipitation Measurement mission of NASA. For more information, see https://www.nasa.gov/mission_pages/GPM/main/index.html.

...

StormSurge

0.4 m

The maximum Storm surge height is  0.4m in Matautu, Samoa. This height is estimated for 09 Feb 2018 14:00 UTC .

The JRC has developed an experimental global storm surge model, which is run after each advisory issued by the regional tropical cyclone centres. The calculations are published about 20 minutes after a new advisory is detected by GDACS. The calculations identify the populated places affected by storm surge up to three days in advance, using the forecasted track. When forecasts change, the associated storm surge changes too and alert levels may go up or down. All links, data, statistics and maps refer to the latest available calculation. If the calculation for the last advisory is not completed, the latest available calculation is shown.

Locations affected by Storm surge (82 locations). Calculation based on advisory number 1 of 09 Feb 2018 00:00:00 UTC. (Simulation using 0.5 minute resolution)

Alert Date (UTC) Name Country Storm surge height (m)
09 Feb 2018 14:00 Matautu Samoa  0.4
09 Feb 2018 12:00 Satupaitea Samoa  0.3
09 Feb 2018 11:00 Salailua Samoa  0.3
09 Feb 2018 13:00 Fuailalo Samoa  0.3
09 Feb 2018 18:00 Iliili American Samoa  0.3
09 Feb 2018 13:00 Puapua Samoa  0.3
12 Feb 2018 17:00 Mua Tonga  0.3
12 Feb 2018 17:00 Kolonga Tonga  0.3
12 Feb 2018 17:00 Niutoua Tonga  0.3
09 Feb 2018 14:00 Faleaseela Samoa  0.2
09 Feb 2018 11:00 Falelima Samoa  0.2
09 Feb 2018 12:00 Gautavai Samoa  0.2
09 Feb 2018 13:00 Samatau Samoa  0.2
09 Feb 2018 18:00 Vaitogi American Samoa  0.2
09 Feb 2018 18:00 Mesepa American Samoa  0.2
09 Feb 2018 18:00 Faleniu American Samoa  0.2
09 Feb 2018 13:00 Fasitootai Samoa  0.2
09 Feb 2018 14:00 Saleimoa Samoa  0.2
09 Feb 2018 19:00 Nuuuli American Samoa  0.2
09 Feb 2018 19:00 Matuu American Samoa  0.2
09 Feb 2018 15:00 Lotofago Samoa  0.2
12 Feb 2018 20:00 Nukunuku Tonga  0.2
12 Feb 2018 20:00 Houma Tonga  0.2
12 Feb 2018 20:00 Pea Tonga  0.2
12 Feb 2018 20:00 Nuku'alofa Tonga  0.2
12 Feb 2018 20:00 Foui Tonga  0.2
09 Feb 2018 10:00 Falealupo Samoa  0.2
09 Feb 2018 15:00 Poutasi Samoa  0.2
09 Feb 2018 18:00 Fagasa American Samoa  0.2
09 Feb 2018 18:00 Pago Pago American Samoa  0.2
09 Feb 2018 18:00 Siufaga American Samoa  0.2
09 Feb 2018 18:00 Fagatogo American Samoa  0.2
09 Feb 2018 18:00 Utulei American Samoa  0.2
09 Feb 2018 18:00 Fagaalu American Samoa  0.2
09 Feb 2018 18:00 Aua American Samoa  0.2
09 Feb 2018 18:00 Lauliifou American Samoa  0.2
12 Feb 2018 16:00 Ohonua Tonga  0.2
09 Feb 2018 18:00 Poloa American Samoa  0.2
09 Feb 2018 18:00 Amanave American Samoa  0.2
09 Feb 2018 18:00 Seetaga American Samoa  0.2
09 Feb 2018 18:00 Aasu American Samoa  0.2
09 Feb 2018 18:00 Amaluia American Samoa  0.2
09 Feb 2018 18:00 Leone American Samoa  0.2
09 Feb 2018 18:00 Vailoatai American Samoa  0.2
09 Feb 2018 18:00 Taputimu American Samoa  0.2
09 Feb 2018 18:00 Futiga American Samoa  0.2
09 Feb 2018 18:00 Pavaiai American Samoa  0.2
12 Feb 2018 17:00 Fuaamotu Tonga  0.2
12 Feb 2018 17:00 Fatumu Tonga  0.2
09 Feb 2018 15:00 Amaile Samoa  0.1
09 Feb 2018 13:00 Salelologa Samoa  0.1
09 Feb 2018 14:00 Utuavanua Samoa  0.1
09 Feb 2018 14:00 Apia Samoa  0.1
09 Feb 2018 17:00 Fagamalo American Samoa  0.1
09 Feb 2018 19:00 Fagaitua American Samoa  0.1
09 Feb 2018 19:00 Aoa American Samoa  0.1
09 Feb 2018 19:00 Onenoa American Samoa  0.1
09 Feb 2018 19:00 Alao American Samoa  0.1
09 Feb 2018 19:00 Tula American Samoa  0.1
09 Feb 2018 15:00 Siumu Samoa  0.1
09 Feb 2018 19:00 Masefau American Samoa  0.1
09 Feb 2018 19:00 Auto American Samoa  0.1
09 Feb 2018 19:00 Alofau American Samoa  0.1
09 Feb 2018 19:00 Amouli American Samoa  0.1
09 Feb 2018 19:00 Aunuu American Samoa  0.1
09 Feb 2018 11:00 Sasina Samoa  0.1
09 Feb 2018 11:00 Leagiaga Samoa  0.1
09 Feb 2018 11:00 Fagamalo Samoa  0.1
09 Feb 2018 14:00 Solosolo Samoa  0.1
09 Feb 2018 18:00 Atuu American Samoa  0.1
09 Feb 2018 18:00 Leloaloa American Samoa  0.1
09 Feb 2018 18:00 Afono American Samoa  0.1
09 Feb 2018 21:00 Tau American Samoa  0.1
09 Feb 2018 21:00 Faleasau American Samoa  0.1
09 Feb 2018 22:00 Faga American Samoa  0.1
09 Feb 2018 22:00 Maia American Samoa  0.1
09 Feb 2018 22:00 Leusoalii American Samoa  0.1
09 Feb 2018 01:00 Mua Wallis and Futuna  0.1
09 Feb 2018 12:00 Tuasivi Samoa  0.1
09 Feb 2018 21:00 Alaufau American Samoa  0.1
09 Feb 2018 21:00 Lalomoana American Samoa  0.1
09 Feb 2018 21:00 Olosega American Samoa  0.1