Category: Extremes affecting Hong Kong

Heat wave occuring from February 21 2026 to March 04 2026 at 20.5°N 110.5°E

Download data: JSON

Event type: Heat wave

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

  • China
  • Hong Kong
  • Lao People’s Democratic Republic
  • Taiwan, Province of China
  • Thailand
  • Viet Nam

Duration: 12 days

Time span: February 21 2026 to March 04 2026

Statistics over entire affected area:

  • Mean temperature anomaly: 2.8 °C
  • Mean temperature: 24.6 °C
  • Maximum temperature anomaly: 8.2 °C
  • Maximum temperature: 29.5 °C

Event center: 20.5°N 110.5°E

Area affected: 1128611 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_2026-Feb-21_to_2026-Mar-04_110.5_20.5

Cold spell occuring from November 18 2025 to November 21 2025 at 18.5°N 108.5°E

Download data: JSON

Event type: Cold spell

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

  • China
  • Hong Kong

Duration: 4 days

Time span: November 18 2025 to November 21 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -4.3 °C
  • Mean temperature: 17.1 °C
  • Minimum temperature anomaly: -7.9 °C
  • Minimum temperature: 5.9 °C

Event center: 18.5°N 108.5°E

Area affected: 419509 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: Cold_spell_2025-Nov-18_to_2025-Nov-21_108.5_18.5

Cold spell occuring from September 30 2025 to November 04 2025 at 50.0°N 100.0°E

Download data: JSON

Event type: Cold spell

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

  • China
  • Hong Kong
  • Japan
  • Kazakhstan
  • Korea, Democratic People’s Republic of
  • Lao People’s Democratic Republic
  • Mongolia
  • Russian Federation
  • United States
  • Viet Nam

Duration: 36 days

Time span: September 30 2025 to November 04 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -5.8 °C
  • Mean temperature: -1.0 °C
  • Minimum temperature anomaly: -23.4 °C
  • Minimum temperature: -32.6 °C

Event center: 50.0°N 100.0°E

Area affected: 19274293 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: Cold_spell_2025-Sep-30_to_2025-Nov-04_100.0_50.0

Cold spell occuring from March 25 2025 to April 09 2025 at 19.0°N 114.0°E

Download data: JSON

Event type: Cold spell

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

  • China
  • Hong Kong
  • Kazakhstan
  • Kyrgyzstan
  • Lao People’s Democratic Republic
  • Mongolia
  • Russian Federation
  • Taiwan, Province of China
  • Tajikistan
  • Thailand
  • Viet Nam

Duration: 16 days

Time span: March 25 2025 to April 09 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -6.8 °C
  • Mean temperature: 6.8 °C
  • Minimum temperature anomaly: -14.5 °C
  • Minimum temperature: -25.8 °C

Event center: 19.0°N 114.0°E

Area affected: 6372090 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: Cold_spell_2025-Mar-25_to_2025-Apr-09_114.0_19.0

Heat wave occuring from March 11 2025 to March 14 2025 at 25.0°N 117.0°E

Download data: JSON

Event type: Heat wave

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

  • China
  • Hong Kong

Duration: 4 days

Time span: March 11 2025 to March 14 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 6.8 °C
  • Mean temperature: 22.3 °C
  • Maximum temperature anomaly: 10.8 °C
  • Maximum temperature: 25.4 °C

Event center: 25.0°N 117.0°E

Area affected: 332397 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-11_to_2025-Mar-14_117.0_25.0

Cold spell occuring from May 31 2024 to June 07 2024 at 26.0°N 118.0°E

Download data: JSON

Event type: Cold spell

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

  • China
  • Hong Kong
  • Taiwan, Province of China

Duration: 8 days

Time span: May 31 2024 to June 07 2024

Statistics over entire affected area:

  • Mean temperature anomaly: -4.2 °C
  • Mean temperature: 21.1 °C
  • Minimum temperature anomaly: -8.5 °C
  • Minimum temperature: 15.0 °C

Event center: 26.0°N 118.0°E

Area affected: 466291 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: Cold_spell_2024-May-31_to_2024-Jun-07_118.0_26.0

Cold spell occuring from January 22 2024 to January 28 2024 at 19.5°N 106.0°E

Download data: JSON

Event type: Cold spell

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

  • China
  • Hong Kong
  • Lao People’s Democratic Republic
  • Viet Nam

Duration: 7 days

Time span: January 22 2024 to January 28 2024

Statistics over entire affected area:

  • Mean temperature anomaly: -6.1 °C
  • Mean temperature: 3.2 °C
  • Minimum temperature anomaly: -11.6 °C
  • Minimum temperature: -17.2 °C

Event center: 19.5°N 106.0°E

Area affected: 1459850 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: Cold_spell_2024-Jan-22_to_2024-Jan-28_106.0_19.5

Cold spell occuring from November 11 2023 to January 24 2024 at 64.0°N 11.5°E

Download data: JSON

Event type: Cold spell

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

  • Austria
  • Belgium
  • China
  • Czechia
  • Denmark
  • Estonia
  • Finland
  • France
  • Germany
  • Hong Kong
  • Ireland
  • Japan
  • Kazakhstan
  • Korea, Democratic People’s Republic of
  • Korea, Republic of
  • Kyrgyzstan
  • Latvia
  • Lithuania
  • Luxembourg
  • Mongolia
  • Netherlands
  • Norway
  • Poland
  • Russian Federation
  • Slovakia
  • Sweden
  • Switzerland
  • Turkmenistan
  • United Kingdom
  • Uzbekistan
  • Viet Nam

Duration: 75 days

Time span: November 11 2023 to January 24 2024

Statistics over entire affected area:

  • Mean temperature anomaly: -10.5 °C
  • Mean temperature: -22.4 °C
  • Minimum temperature anomaly: -30.3 °C
  • Minimum temperature: -58.1 °C

Event center: 64.0°N 11.5°E

Area affected: 29695508 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: Cold_spell_2023-Nov-11_to_2024-Jan-24_11.5_64.0

Cold spell occuring from October 07 2023 to October 11 2023 at 24.0°N 115.0°E

Download data: JSON

Event type: Cold spell

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

  • China
  • Hong Kong

Duration: 5 days

Time span: October 07 2023 to October 11 2023

Statistics over entire affected area:

  • Mean temperature anomaly: -3.8 °C
  • Mean temperature: 20.7 °C
  • Minimum temperature anomaly: -5.5 °C
  • Minimum temperature: 17.3 °C

Event center: 24.0°N 115.0°E

Area affected: 122094 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: Cold_spell_2023-Oct-07_to_2023-Oct-11_115.0_24.0

Cold spell occuring from September 06 2023 to September 11 2023 at 23.0°N 113.5°E

Download data: JSON

Event type: Cold spell

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

  • China
  • Hong Kong

Duration: 6 days

Time span: September 06 2023 to September 11 2023

Statistics over entire affected area:

  • Mean temperature anomaly: -2.1 °C
  • Mean temperature: 25.3 °C
  • Minimum temperature anomaly: -3.0 °C
  • Minimum temperature: 23.3 °C

Event center: 23.0°N 113.5°E

Area affected: 116819 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: Cold_spell_2023-Sep-06_to_2023-Sep-11_113.5_23.0