Category: Heat waves affecting Tonga

Heat wave occuring from August 20 2025 to September 11 2025 at -13.0°S 192.5°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Australia
  • Fiji
  • New Zealand
  • Tonga

Duration: 23 days

Time span: August 20 2025 to September 11 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 1.7 °C
  • Mean temperature: 20.5 °C
  • Maximum temperature anomaly: 3.6 °C
  • Maximum temperature: 28.0 °C

Event center: -13.0°S 192.5°E

Area affected: 6868306 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2025-Aug-20_to_2025-Sep-11_192.5_-13.0

Heat wave occuring from March 18 2025 to March 31 2025 at -19.5°S 185.5°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Tonga

Duration: 14 days

Time span: March 18 2025 to March 31 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 1.1 °C
  • Mean temperature: 27.2 °C
  • Maximum temperature anomaly: 1.9 °C
  • Maximum temperature: 28.4 °C

Event center: -19.5°S 185.5°E

Area affected: 303387 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2025-Mar-18_to_2025-Mar-31_185.5_-19.5

Heat wave occuring from May 27 2023 to June 02 2023 at -14.5°S 178.5°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Fiji
  • Tonga

Duration: 7 days

Time span: May 27 2023 to June 02 2023

Statistics over entire affected area:

  • Mean temperature anomaly: 1.8 °C
  • Mean temperature: 25.2 °C
  • Maximum temperature anomaly: 3.1 °C
  • Maximum temperature: 28.3 °C

Event center: -14.5°S 178.5°E

Area affected: 1107534 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2023-May-27_to_2023-Jun-02_178.5_-14.5

Heat wave occuring from December 28 2022 to February 11 2023 at -22.0°S 174.5°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Australia
  • Fiji
  • New Caledonia
  • New Zealand
  • Norfolk Island
  • Papua New Guinea
  • Solomon Islands
  • Tonga
  • Vanuatu

Duration: 46 days

Time span: December 28 2022 to February 11 2023

Statistics over entire affected area:

  • Mean temperature anomaly: 2.1 °C
  • Mean temperature: 21.6 °C
  • Maximum temperature anomaly: 11.2 °C
  • Maximum temperature: 29.4 °C

Event center: -22.0°S 174.5°E

Area affected: 15248407 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2022-Dec-28_to_2023-Feb-11_174.5_-22.0

Heat wave occuring from October 11 2022 to November 06 2022 at -25.5°S 196.5°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Tonga

Duration: 27 days

Time span: October 11 2022 to November 06 2022

Statistics over entire affected area:

  • Mean temperature anomaly: 2.2 °C
  • Mean temperature: 17.9 °C
  • Maximum temperature anomaly: 4.0 °C
  • Maximum temperature: 26.7 °C

Event center: -25.5°S 196.5°E

Area affected: 9008122 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2022-Oct-11_to_2022-Nov-06_196.5_-25.5

Heat wave occuring from June 01 2022 to June 05 2022 at -18.5°S 186.0°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Tonga

Duration: 5 days

Time span: June 01 2022 to June 05 2022

Statistics over entire affected area:

  • Mean temperature anomaly: 1.6 °C
  • Mean temperature: 26.1 °C
  • Maximum temperature anomaly: 2.1 °C
  • Maximum temperature: 27.0 °C

Event center: -18.5°S 186.0°E

Area affected: 113501 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2022-Jun-01_to_2022-Jun-05_186.0_-18.5

Heat wave occuring from March 17 2022 to March 23 2022 at -17.0°S 184.5°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Fiji
  • Tonga

Duration: 7 days

Time span: March 17 2022 to March 23 2022

Statistics over entire affected area:

  • Mean temperature anomaly: 1.2 °C
  • Mean temperature: 27.7 °C
  • Maximum temperature anomaly: 2.3 °C
  • Maximum temperature: 28.9 °C

Event center: -17.0°S 184.5°E

Area affected: 1767134 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2022-Mar-17_to_2022-Mar-23_184.5_-17.0

Heat wave occuring from February 19 2022 to January 25 2023 at -11.0°S 150.0°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Antarctica
  • Australia
  • Bangladesh
  • Bhutan
  • Cambodia
  • Canada
  • China
  • Christmas Island
  • Cook Islands
  • Fiji
  • French Polynesia
  • Hong Kong
  • India
  • Indonesia
  • Japan
  • Kazakhstan
  • Korea, Democratic People’s Republic of
  • Korea, Republic of
  • Kyrgyzstan
  • Lao People’s Democratic Republic
  • Malaysia
  • Maldives
  • Mongolia
  • Myanmar
  • Nepal
  • New Caledonia
  • New Zealand
  • Norfolk Island
  • Northern Mariana Islands
  • Oman
  • Pakistan
  • Papua New Guinea
  • Philippines
  • Russian Federation
  • Solomon Islands
  • Sri Lanka
  • Taiwan, Province of China
  • Thailand
  • Timor-Leste
  • Tonga
  • United States
  • Vanuatu
  • Viet Nam

Duration: 341 days

Time span: February 19 2022 to January 25 2023

Statistics over entire affected area:

  • Mean temperature anomaly: 2.6 °C
  • Mean temperature: 19.0 °C
  • Maximum temperature anomaly: 33.4 °C
  • Maximum temperature: 37.4 °C

Event center: -11.0°S 150.0°E

Area affected: 154052228 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2022-Feb-19_to_2023-Jan-25_150.0_-11.0

Heat wave occuring from May 01 2021 to June 04 2021 at -21.5°S 174.0°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Australia
  • Fiji
  • French Polynesia
  • Indonesia
  • New Caledonia
  • New Zealand
  • Norfolk Island
  • Papua New Guinea
  • Samoa
  • Solomon Islands
  • Timor-Leste
  • Tonga
  • Vanuatu

Duration: 35 days

Time span: May 01 2021 to June 04 2021

Statistics over entire affected area:

  • Mean temperature anomaly: 1.7 °C
  • Mean temperature: 23.6 °C
  • Maximum temperature anomaly: 7.4 °C
  • Maximum temperature: 29.5 °C

Event center: -21.5°S 174.0°E

Area affected: 20386096 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2021-May-01_to_2021-Jun-04_174.0_-21.5

Heat wave occuring from April 19 2021 to April 24 2021 at -21.5°S 187.0°E

Download data: JSON

Event type: Heat wave

Countries affected (identified with ArcGIS Online; provided only for geographical reference):

  • Tonga

Duration: 6 days

Time span: April 19 2021 to April 24 2021

Statistics over entire affected area:

  • Mean temperature anomaly: 1.3 °C
  • Mean temperature: 26.3 °C
  • Maximum temperature anomaly: 2.0 °C
  • Maximum temperature: 27.2 °C

Event center: -21.5°S 187.0°E

Area affected: 132147 km$^2$


Fig. 1: Map of most extreme temperature anomalies (standardized) experienced during the event. The purple star indicates the center of the extreme event. Green hatching illustrates all areas under the effect of extremes at some time during the event.



Fig. 2: Evolution of temperature at the center of the event. The climatological percentile distribution is illustrated with color shadings.



Fig. 3: Maps illustrating the evolution of standardized temperature anomalies during the event.

Event ID: Heat_wave_2021-Apr-19_to_2021-Apr-24_187.0_-21.5