Overall Green alert Tropical Cyclone for ZAZU-20
in Niue, Tonga
14 Dec 2020 06 UTC
click on to select bulletin time
  • GDACS JTWC
Impact Single TC
Impact based on all weather systems in the area

Impact

    Tropical Cyclone ZAZU-20 can have a low humanitarian impact based on the maximum sustained wind speed,exposed population and vulnerability.

    Meteorological source GDACS
    Exposed countries Niue, Tonga
    Exposed population No people in Category 1 or higher
    Maximum wind speed 102 km/h
    Maximum storm surge 0.3 m (14 Dec 19:00 UTC)
    Vulnerability High (Niue)

    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
    Current 111 km/h 0.3 m n.a. 0.5
    Overall 102 km/h 0.3 m n.a. 0.5

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

    TOP

    Wind

      111 km/h Current Max.

      Up to 110000 people in Tropical Storm strength or higher (see SSHS)

      Impact Timeline

        Alert N° Date (UTC) Max Winds (km/h) Population in
        Tropical Storm or higher        		 Population in
        Cat 1. or higher        		 Countries
        Green 1 13 Dec 2020 12:00 102 110 thousand No people Tonga, Niue
        Green 2 13 Dec 2020 18:00 102 110 thousand No people Tonga, Niue
        Green 3 14 Dec 2020 00:00 111 30 thousand No people Tonga, Niue
        Green 4 14 Dec 2020 06:00 111 110 thousand No people Tonga, Niue

        Bulletin Timeline

          Alert N° Date (UTC) Category
          (SSHS)           		Max winds
          (km/h)           		Population in
          Cat.1 or higher           		Population in
          Tropical Storm
          or higher           		Location (lat, lon) Countries
          GREEN
          		 1 13 Dec 2020 12:00 Tropical storm 65 no people 23000 people -17, -173.4
          GREEN
          		 2 13 Dec 2020 18:00 Tropical storm 65 no people 22000 people -17.7, -173.8
          GREEN
          		 3 14 Dec 2020 00:00 Tropical storm 74 no people 23000 people -17.9, -174.1
          GREEN
          		 4 14 Dec 2020 06:00 Tropical storm 83 no people 100000 people -18.3, -174.3
          GREEN
          		 4 14 Dec 2020 18:00 Tropical storm 93 no people 110000 people -18.9, -174.3
          GREEN
          		 4 15 Dec 2020 06:00 Tropical storm 102 no people 110000 people -19.5, -173.3
          GREEN
          		 4 15 Dec 2020 18:00 Tropical storm 111 no people 6400 people -20.5, -171.7
          GREEN
          		 4 16 Dec 2020 06:00 Tropical storm 102 no people no people -22.2, -169.7
          GREEN
          		 4 17 Dec 2020 06:00 Tropical storm 83 no people no people -27.3, -166.3
          Actual track of the current bulletin
          The alert for forecast greater than 3 days is limited to Orange level.
          Download:



          Exposed population - AoIs

          Exposed population in the potential affected countries, provinces and populated places

          Countries

          Country
          Tonga
          Niue

          Provinces

          Region Province Country
          Tonga Tonga
          Niue Niue

          Populated places

          Name Region Province Country City class Population
          Nuku'alofa Tonga Capital 24000 people
          Alofi Niue Capital <1000 people

          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)
          Vavau International VAV 72 Civ. Unpaved Yes 5500
          Haapai HPA 12 Civ. Unpaved Yes 3900
          Fua'amotu International TBU 38 Civ. Paved Yes 8700
          Eua Kaufana EUA unknown 0
          Niue Hanan IUE 64 Civ. Paved Yes 7600

          Ports

          Name LOCODE Country
          Neiafu TONEI Tonga
          Pangai TOPAN Tonga
          Nuku'alofa TOTBU Tonga
          Eua Island Tonga
          Alofi Niue
          TOP

          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.

          ...

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          StormSurge

          0.3 m

          The maximum Storm surge height is  0.3m in Neiafu, Tonga. This height is estimated for 14 Dec 2020 19:00 UTC .

          The JRC has developed an experimental global storm surge model. 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 (2 locations). Calculation based on advisory number 4 of 14 Dec 2020 06:00:00 UTC. (Simulation using 6 minute resolution)

          Alert Date (UTC) Name Country Storm surge height (m)
          14 Dec 2020 19:00 Neiafu Tonga  0.3
          15 Dec 2020 08:00 Pangai Tonga  0.1