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 0.8 m (12 Feb 11:00 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 213 km/h 0.8 m n.a. 0.5
GDACS Overall 231 km/h 0.8 m n.a. 2.5

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

Wind

213 km/h Current

Up to 83000 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
Orange 2 09 Feb 2018 06:00 148 400 thousand 80 thousand Tonga
Orange 3 09 Feb 2018 12:00 148 930 thousand 80 thousand Tonga
Orange 4 09 Feb 2018 18:00 139 830 thousand 80 thousand Tonga
Orange 5 10 Feb 2018 00:00 139 820 thousand 80 thousand Tonga
Orange 6 10 Feb 2018 06:00 139 600 thousand 80 thousand Tonga
Orange 7 10 Feb 2018 12:00 130 670 thousand 80 thousand Tonga
Orange 8 10 Feb 2018 18:00 176 770 thousand 80 thousand Tonga
Green 9 11 Feb 2018 00:00 204 390 thousand Few people affected Niue, Tonga, American Samoa, Wallis and Futuna, Fiji
Red 10 11 Feb 2018 06:00 185 1.1 million 80 thousand Tonga
Red 11 11 Feb 2018 12:00 185 980 thousand 80 thousand Tonga
Red 12 11 Feb 2018 18:00 185 1.1 million 80 thousand Tonga
Red 13 12 Feb 2018 00:00 213 790 thousand 80 thousand Tonga
Red 14 12 Feb 2018 06:00 231 540 thousand 80 thousand Tonga
Red 15 12 Feb 2018 12:00 231 360 thousand 80 thousand Tonga
Green 16 12 Feb 2018 18:00 231 970 thousand 80 thousand Tonga
Green 17 13 Feb 2018 00:00 222 800 thousand 80 thousand Tonga
Green 18 13 Feb 2018 06:00 213 740 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
2 09 Feb 2018 06:00 Tropical storm 74 260000 people no people -14.3, -174.5 Niue
GREEN
3 09 Feb 2018 12:00 Tropical storm 83 250000 people no people -14.5, -173 Niue
GREEN
4 09 Feb 2018 18:00 Tropical storm 83 250000 people no people -15.3, -171.4 Niue
GREEN
5 10 Feb 2018 00:00 Tropical storm 93 200000 people no people -16.1, -170 Niue
GREEN
6 10 Feb 2018 06:00 Tropical storm 93 1100 people no people -17, -169 Niue
GREEN
7 10 Feb 2018 12:00 Tropical storm 102 1100 people no people -18.2, -168.5 Niue
GREEN
8 10 Feb 2018 18:00 Category 1 139 1100 people no people -18.9, -168.6 Niue
GREEN
9 11 Feb 2018 00:00 Category 2 157 1100 people no people -20.5, -168.3 Niue
GREEN
10 11 Feb 2018 06:00 Category 2 167 6200 people no people -20.9, -168.9 Niue
GREEN
11 11 Feb 2018 12:00 Category 2 167 100000 people no people -21.4, -170.2 Niue
GREEN
12 11 Feb 2018 18:00 Category 2 176 100000 people no people -21.7, -171.5 Tonga
RED
13 12 Feb 2018 00:00 Category 3 204 100000 people 82000 people -21.8, -172.6 Tonga
RED
14 12 Feb 2018 06:00 Category 4 231 90000 people 82000 people -21.8, -174.3 Tonga
RED
15 12 Feb 2018 12:00 Category 4 231 84000 people 83000 people -21.5, -175.5 Tonga
GREEN
16 12 Feb 2018 18:00 Category 4 231 100000 people <1000 people -21.3, -177.1 Fiji
GREEN
17 13 Feb 2018 00:00 Category 4 222 80000 people <1000 people -21.2, -178.4 Fiji
GREEN
18 13 Feb 2018 06:00 Category 4 213 340000 people <1000 people -21, -179.5 Fiji
GREEN
18 13 Feb 2018 18:00 Category 3 204 340000 people no people -21, 178.7 Fiji
GREEN
18 14 Feb 2018 06:00 Category 3 194 13000 people no people -21.2, 176.9 Fiji
GREEN
18 14 Feb 2018 18:00 Category 3 185 <1000 people no people -21.6, 175.3
GREEN
18 15 Feb 2018 06:00 Category 2 176 14000 people <1000 people -22, 173.5 New Caledonia
GREEN
18 16 Feb 2018 06:00 Category 2 157 26000 people no people -23.8, 169.7 New Caledonia
GREEN
18 17 Feb 2018 06:00 Category 1 120 2200 people no people -26.4, 166.8 Norfolk Island
GREEN
18 18 Feb 2018 06:00 Tropical storm 93 no people no people -30.1, 165.1
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 445 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
Ono-I-Lau ONU unknown 0 92 km
Fua'amotu International TBU 38 Civ. Paved Yes 8700 453 km
Eua Kaufana EUA unknown 0 474 km

Ports

Name LOCODE Country Distance
Nuku'alofa TOTBU Tonga 447 km
Eua Island Tonga 479 km
Hunter Island New Caledonia 887 km
Matthew Island New Caledonia 959 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

0.8 m

The maximum Storm surge height is  0.8m in Fuaamotu, Tonga. This height is estimated for 12 Feb 2018 11:00 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 (32 locations). Calculation based on advisory number 18 of 13 Feb 2018 06:00:00 UTC. (Simulation using 0.5 minute resolution)

Alert Date (UTC) Name Country Storm surge height (m)
12 Feb 2018 11:00 Fuaamotu Tonga  0.8
12 Feb 2018 11:00 Fatumu Tonga  0.8
12 Feb 2018 11:00 Ohonua Tonga  0.8
12 Feb 2018 12:00 Nukunuku Tonga  0.7
12 Feb 2018 12:00 Houma Tonga  0.7
12 Feb 2018 12:00 Pea Tonga  0.7
12 Feb 2018 12:00 Nuku'alofa Tonga  0.7
12 Feb 2018 12:00 Mua Tonga  0.7
12 Feb 2018 12:00 Foui Tonga  0.7
12 Feb 2018 11:00 Kolonga Tonga  0.5
12 Feb 2018 11:00 Niutoua Tonga  0.5
16 Feb 2018 12:00 Gadji New Caledonia  0.2
16 Feb 2018 16:00 Kuto New Caledonia  0.2
16 Feb 2018 16:00 Vao New Caledonia  0.2
16 Feb 2018 11:00 Wapan New Caledonia  0.2
16 Feb 2018 12:00 Ouara New Caledonia  0.1
13 Feb 2018 07:00 Naruwai Fiji  0.1
16 Feb 2018 07:00 Plum New Caledonia  0.1
13 Feb 2018 09:00 Navindamu Fiji  0.1
16 Feb 2018 10:00 Prony New Caledonia  0.1
16 Feb 2018 07:00 Yate-Village New Caledonia  0.1
16 Feb 2018 07:00 Waho New Caledonia  0.1
16 Feb 2018 07:00 Goro New Caledonia  0.1
13 Feb 2018 07:00 Ndalomo Fiji  0.1
13 Feb 2018 10:00 Nawailevu Fiji  0.1
13 Feb 2018 08:00 Savu Sau Fiji  0.1
13 Feb 2018 08:00 Navinggiri Fiji  0.1
16 Feb 2018 07:00 Saint-Louis New Caledonia  0.1
09 Feb 2018 01:00 Mua Wallis and Futuna  0.1
09 Feb 2018 01:00 Mata-Utu Wallis and Futuna  0.1
13 Feb 2018 07:00 Koroinasolo Fiji  0.1
13 Feb 2018 08:00 Nagumu Fiji  0.1