Working Group on Tropical Meteorology Research (WG TMR) Workshop: Cyclone Types and Phase Transitions

Workshop:
Cyclone Types and Phase Transitions
11 - 13 November 2025

Online

Purpose:

This workshop, organized by the WWRP Working Group on Tropical Meteorology Research (WG TMR), responds to Recommendation 14 from the 10th International Workshop on Tropical Cyclones (IWTC-10), which highlighted the need to develop basin-specific approaches to defining cyclone types (tropical, subtropical, extratropical cyclones, medicanes) and their transition pathways, and to further develop and share diagnostic techniques building on the cyclone phase space.

Registration link: https://wmo-int.zoom.us/meeting/register/7II8HKnxT76n9zX5a6FDPw

Agenda

The programme will include invited presentations and interactive breakout discussions covering:

Session 1 (11 Nov): Tropical cyclones and the extratropical transition
Session 2 (12 Nov): Subtropical cyclones and tropical transition
Session 3 (13 Nov): Medicanes, Summary and next steps

Please find the tentative agenda:

Date	Time	Title and Speaker
11 Nov	00:00-00:05	Opening remarks
	Session 1: Tropical cyclones and extratropical transition
	00:05-00:30 UTC	Extratropical transition as one example of a tropical cyclone lifecycle within a generalized cyclone phase space Dr. Robert Hart (FSU)
	00:30-00:55 UTC	JMA Operational Analysis/Forecasting on Extratropical Transition of Tropical Cyclones Dr. Nao Takamura (RSMC Tokyo)
	00:55-01:20 UTC	Evaluation of ET cases from WP-MIP Dr. Ron MacTaggart-Cowan (ECCC)
	01:20–01:45 UTC	Breakout Discussion
	01:45-02:00 UTC	Reflections from breakout groups and discussion
12 Nov	Session 2: Subtropical cyclones and tropical transition
	00:00-00:25 UTC	Definition of subtropical cyclone Dr. John Beven (NOAA)
	00:25-00:50 UTC	A case study on Tropical Cyclone Alfred Dr. Craig Earl-Spurr (BOM)
	00:50-01:15 UTC	Phase transitions between tropical, subtropical, and extratropical cyclones: A review from IWTC-10 Dr. Kim Wood (UA)
	01:15–01:40 UTC	Breakout Discussion
	01:40-02:00 UTC	Reflections from breakout groups and discussion
13 Nov	00:00-00:25 UTC	Physical and operational implications of medicanes' physical definition Dr. Emmanouil Flaounas (HCMR)
	Session 3: Summary and next steps * Recap of discussions, identification of gaps and priorities, agreement on writing team(s) and plan
	00:25-00:35 UTC	Session 1 Rapporteurs- presentation
	00:35-00:45 UTC	Session 2 Rapporteurs- presentation
	00:45-00:55 UTC	Reflection from Co-chairs
	00:55-01:30 UTC	Discussion on Gaps and Priorities
	01:30-02:00 UTC	Next Steps

Organizing Committee:

Michelle  Simões REBOITA, Universidade Federal de Itajubá, Brazil

Wataru YANASE, Japan Meteorological Agency, Japan

Zhuo WANG, University of Illinois, United States of America

Parthasarathi MUKHOPADHYAY, Indian Institute of Science Education and Research (IISER), India

Contact: Liye LI, WWRP Secretariat, lli@wmo.int