Category: Heat waves affecting New Zealand

Heat wave occuring from September 13 2025 to September 17 2025 at -37.5°S 153.0°E

Download data: JSON

Event type: Heat wave

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

  • Australia
  • New Zealand

Duration: 5 days

Time span: September 13 2025 to September 17 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 2.5 °C
  • Mean temperature: 14.7 °C
  • Maximum temperature anomaly: 6.6 °C
  • Maximum temperature: 21.7 °C

Event center: -37.5°S 153.0°E

Area affected: 1656781 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-Sep-13_to_2025-Sep-17_153.0_-37.5

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 August 16 2025 to August 29 2025 at -48.0°S 147.5°E

Download data: JSON

Event type: Heat wave

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

  • Australia
  • New Zealand

Duration: 14 days

Time span: August 16 2025 to August 29 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 2.6 °C
  • Mean temperature: 8.5 °C
  • Maximum temperature anomaly: 8.6 °C
  • Maximum temperature: 19.5 °C

Event center: -48.0°S 147.5°E

Area affected: 7459285 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-16_to_2025-Aug-29_147.5_-48.0

Heat wave occuring from August 14 2025 to August 16 2025 at -49.0°S 172.0°E

Download data: JSON

Event type: Heat wave

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

  • New Zealand

Duration: 3 days

Time span: August 14 2025 to August 16 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 2.2 °C
  • Mean temperature: 9.5 °C
  • Maximum temperature anomaly: 3.2 °C
  • Maximum temperature: 12.1 °C

Event center: -49.0°S 172.0°E

Area affected: 200558 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-14_to_2025-Aug-16_172.0_-49.0

Heat wave occuring from August 02 2025 to August 08 2025 at -48.0°S 150.5°E

Download data: JSON

Event type: Heat wave

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

  • Antarctica
  • Australia
  • New Zealand

Duration: 7 days

Time span: August 02 2025 to August 08 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 3.0 °C
  • Mean temperature: 6.7 °C
  • Maximum temperature anomaly: 6.1 °C
  • Maximum temperature: 16.0 °C

Event center: -48.0°S 150.5°E

Area affected: 4227888 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-02_to_2025-Aug-08_150.5_-48.0

Heat wave occuring from August 01 2025 to August 07 2025 at -43.5°S 169.0°E

Download data: JSON

Event type: Heat wave

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

  • New Zealand

Duration: 7 days

Time span: August 01 2025 to August 07 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 2.1 °C
  • Mean temperature: 12.6 °C
  • Maximum temperature anomaly: 3.2 °C
  • Maximum temperature: 15.3 °C

Event center: -43.5°S 169.0°E

Area affected: 475009 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-01_to_2025-Aug-07_169.0_-43.5

Heat wave occuring from July 18 2025 to August 01 2025 at -50.5°S 163.0°E

Download data: JSON

Event type: Heat wave

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

  • New Zealand

Duration: 15 days

Time span: July 18 2025 to August 01 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 2.4 °C
  • Mean temperature: 12.3 °C
  • Maximum temperature anomaly: 6.2 °C
  • Maximum temperature: 20.9 °C

Event center: -50.5°S 163.0°E

Area affected: 5441040 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-Jul-18_to_2025-Aug-01_163.0_-50.5

Heat wave occuring from June 12 2025 to June 19 2025 at -48.5°S 151.5°E

Download data: JSON

Event type: Heat wave

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

  • Australia
  • New Zealand

Duration: 8 days

Time span: June 12 2025 to June 19 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 2.6 °C
  • Mean temperature: 11.2 °C
  • Maximum temperature anomaly: 4.2 °C
  • Maximum temperature: 14.6 °C

Event center: -48.5°S 151.5°E

Area affected: 898467 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-Jun-12_to_2025-Jun-19_151.5_-48.5

Heat wave occuring from April 09 2025 to April 13 2025 at -46.0°S 172.0°E

Download data: JSON

Event type: Heat wave

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

  • New Zealand

Duration: 5 days

Time span: April 09 2025 to April 13 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 2.5 °C
  • Mean temperature: 13.2 °C
  • Maximum temperature anomaly: 3.6 °C
  • Maximum temperature: 14.7 °C

Event center: -46.0°S 172.0°E

Area affected: 191601 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-Apr-09_to_2025-Apr-13_172.0_-46.0

Heat wave occuring from April 02 2025 to April 04 2025 at -46.5°S 171.5°E

Download data: JSON

Event type: Heat wave

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

  • New Zealand

Duration: 3 days

Time span: April 02 2025 to April 04 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 2.8 °C
  • Mean temperature: 15.4 °C
  • Maximum temperature anomaly: 4.7 °C
  • Maximum temperature: 18.8 °C

Event center: -46.5°S 171.5°E

Area affected: 320897 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-Apr-02_to_2025-Apr-04_171.5_-46.5