Category: Extremes affecting United States

Cold spell occuring from May 18 2025 to May 25 2025 at 62.5°N 179.0°E

Download data: JSON

Event type: Cold spell

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

  • Russian Federation
  • United States

Duration: 8 days

Time span: May 18 2025 to May 25 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -2.6 °C
  • Mean temperature: -2.3 °C
  • Minimum temperature anomaly: -5.4 °C
  • Minimum temperature: -6.3 °C

Event center: 62.5°N 179.0°E

Area affected: 534076 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-May-18_to_2025-May-25_179.0_62.5

Cold spell occuring from May 16 2025 to May 28 2025 at 47.0°N 258.5°E

Download data: JSON

Event type: Cold spell

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

  • Canada
  • United States

Duration: 13 days

Time span: May 16 2025 to May 28 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -7.3 °C
  • Mean temperature: 6.2 °C
  • Minimum temperature anomaly: -10.8 °C
  • Minimum temperature: 0.7 °C

Event center: 47.0°N 258.5°E

Area affected: 847874 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-May-16_to_2025-May-28_258.5_47.0

Cold spell occuring from May 11 2025 to May 16 2025 at 67.0°N 218.0°E

Download data: JSON

Event type: Cold spell

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

  • Canada
  • United States

Duration: 6 days

Time span: May 11 2025 to May 16 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -7.6 °C
  • Mean temperature: -3.8 °C
  • Minimum temperature anomaly: -11.5 °C
  • Minimum temperature: -11.2 °C

Event center: 67.0°N 218.0°E

Area affected: 276503 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-May-11_to_2025-May-16_218.0_67.0

Cold spell occuring from May 10 2025 to May 12 2025 at 29.5°N 267.0°E

Download data: JSON

Event type: Cold spell

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

  • United States

Duration: 3 days

Time span: May 10 2025 to May 12 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -3.2 °C
  • Mean temperature: 20.8 °C
  • Minimum temperature anomaly: -7.3 °C
  • Minimum temperature: 15.8 °C

Event center: 29.5°N 267.0°E

Area affected: 201940 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-May-10_to_2025-May-12_267.0_29.5

Heat wave occuring from May 09 2025 to May 13 2025 at 27.0°N 246.5°E

Download data: JSON

Event type: Heat wave

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

  • Mexico
  • United States

Duration: 5 days

Time span: May 09 2025 to May 13 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 5.3 °C
  • Mean temperature: 28.9 °C
  • Maximum temperature anomaly: 11.8 °C
  • Maximum temperature: 35.1 °C

Event center: 27.0°N 246.5°E

Area affected: 312208 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-May-09_to_2025-May-13_246.5_27.0

Heat wave occuring from May 08 2025 to May 17 2025 at 47.5°N 259.0°E

Download data: JSON

Event type: Heat wave

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

  • Canada
  • Mexico
  • United States

Duration: 10 days

Time span: May 08 2025 to May 17 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 9.3 °C
  • Mean temperature: 20.0 °C
  • Maximum temperature anomaly: 19.9 °C
  • Maximum temperature: 33.6 °C

Event center: 47.5°N 259.0°E

Area affected: 3663517 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-May-08_to_2025-May-17_259.0_47.5

Cold spell occuring from May 05 2025 to May 07 2025 at 33.5°N 248.0°E

Download data: JSON

Event type: Cold spell

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

  • United States

Duration: 3 days

Time span: May 05 2025 to May 07 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -6.7 °C
  • Mean temperature: 16.7 °C
  • Minimum temperature anomaly: -7.9 °C
  • Minimum temperature: 11.9 °C

Event center: 33.5°N 248.0°E

Area affected: 53443 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-May-05_to_2025-May-07_248.0_33.5

Cold spell occuring from May 05 2025 to May 09 2025 at 37.0°N 254.0°E

Download data: JSON

Event type: Cold spell

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

  • United States

Duration: 5 days

Time span: May 05 2025 to May 09 2025

Statistics over entire affected area:

  • Mean temperature anomaly: -6.9 °C
  • Mean temperature: 7.9 °C
  • Minimum temperature anomaly: -10.4 °C
  • Minimum temperature: -0.2 °C

Event center: 37.0°N 254.0°E

Area affected: 151116 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-May-05_to_2025-May-09_254.0_37.0

Heat wave occuring from May 04 2025 to May 06 2025 at 49.5°N 264.5°E

Download data: JSON

Event type: Heat wave

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

  • Canada
  • United States

Duration: 3 days

Time span: May 04 2025 to May 06 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 7.6 °C
  • Mean temperature: 17.4 °C
  • Maximum temperature anomaly: 12.9 °C
  • Maximum temperature: 22.3 °C

Event center: 49.5°N 264.5°E

Area affected: 81073 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-May-04_to_2025-May-06_264.5_49.5

Heat wave occuring from May 03 2025 to May 05 2025 at 52.0°N 257.5°E

Download data: JSON

Event type: Heat wave

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

  • Canada
  • United States

Duration: 3 days

Time span: May 03 2025 to May 05 2025

Statistics over entire affected area:

  • Mean temperature anomaly: 8.5 °C
  • Mean temperature: 16.5 °C
  • Maximum temperature anomaly: 13.9 °C
  • Maximum temperature: 22.2 °C

Event center: 52.0°N 257.5°E

Area affected: 89710 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-May-03_to_2025-May-05_257.5_52.0