Giannakopoulos et al. (2025) Examining the Characteristics and Evolution of Wintertime Temperature Whiplash Events in the U.S. Southern Plains

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Journal of Climate
• Year: 2025
• Date: 2025-11-26
• Authors: Katherine L. Giannakopoulos, Jason C. Furtado
• DOI: 10.1175/jcli-d-24-0572.1

Research Groups

Not specified in the provided abstract.

Short Summary

This study defines and characterizes rapid extreme temperature swings, termed "temperature whiplashes," in the U.S. southern plains during winter, identifying specific atmospheric and stratospheric precursors that offer opportunities for improved subseasonal to seasonal predictions.

Objective

• To define and characterize temperature whiplash events (hot to cold and cold to hot) in the U.S. southern plains during winter.
• To investigate the potential for long-range predictions of these extreme temperature events by identifying precursor atmospheric and stratospheric patterns.

Study Configuration

• Spatial Scale: U.S. southern plains (primary focus), North Pacific, eastern Siberia/western Alaska, Canada (for precursor atmospheric patterns).
• Temporal Scale: 1950 to 2023 (December–February) for data analysis; day-to-day changes for event definition; subseasonal to seasonal scale for potential predictions.

Methodology and Data

• Models used: Temperature Swing Index (TSI) for event definition and characterization.
• Data sources: Fifth generation European Centre for Medium-Range Weather Forecasts atmospheric reanalysis (ERA5).

Main Results

• Two types of temperature whiplashes were defined: hot to cold and cold to hot.
• Temperature whiplash events were identified using a Temperature Swing Index (TSI), with "high swing days" (HSDs) exceeding the 90th percentile.
• Hot-to-cold whiplashes are preceded by an amplifying Rossby wave train and an atmospheric blocking pattern in the North Pacific in the midtroposphere.
• These events coincide with an increasingly distorted and "stretched" stratospheric polar vortex at 50 hPa.
• Statistically significant upward flux over eastern Siberia/western Alaska and downward flux over Canada suggest possible stratospheric wave reflection prior to HSDs.
• These identified characteristics present particular forecast opportunities to improve predictions of extreme temperature events on a subseasonal to seasonal scale.

Contributions

• Provides a regional definition and characterization of temperature whiplash events specifically for the U.S. southern plains during winter.
• Identifies novel atmospheric (Rossby wave train, North Pacific blocking) and stratospheric (distorted polar vortex, stratospheric wave reflection) precursor signals for these events.
• Highlights the potential for improved long-range (subseasonal to seasonal) prediction of temperature whiplash events based on these identified precursors.

Funding

Not specified in the provided abstract.

Citation

@article{Giannakopoulos2025Examining,
  author = {Giannakopoulos, Katherine L. and Furtado, Jason C.},
  title = {Examining the Characteristics and Evolution of Wintertime Temperature Whiplash Events in the U.S. Southern Plains},
  journal = {Journal of Climate},
  year = {2025},
  doi = {10.1175/jcli-d-24-0572.1},
  url = {https://doi.org/10.1175/jcli-d-24-0572.1}
}