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: 

The Working Group on Tropical Meteorology Research (WGTMR) of the WWRP of WMO is organizing a workshop, in response 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, as well as to further develop and share diagnostic techniques building on the cyclone phase space. 

Date: 11–13 November 2025 
Time: 00:00–02:00 UTC each day 
Format: Online (Zoom) 

Registration Deadline: 24 UTC, 4 November 2025 

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): Medicanes, Subtropical cyclones and tropical transition 

  • Session 3 (13 Nov): Summary and next steps 

 

Please find the tentative agenda:  

Date  

Time  

Title and Speaker  

 

11 Nov 

00:00-00:05 UTC  

Opening remarks  

Kunio YONEYAMA (WWRP SSC) 

Session 1 

Lead :  MichelleSimões REBOITA (UNIFEI) 

Rapporteur : TBD 

00:05-00:30 UTC  

Phase transitions between tropical, subtropical, and extratropical cyclones: A review from IWTC-10  

Kim Wood (UA) 

00:30-00:55 UTC  

Extratropical transition as one example of a tropical cyclone lifecycle within a generalized cyclone phase space  

 Robert Hart (FSU)  

00:55-01:20 UTC  

JMA Operational Analysis/Forecasting onExtratropical Transition of Tropical Cyclones  

Nao Takamura (JMA)  

01:20–01:50 UTC  

Breakout Discussion  

01:50-02:00 UTC  

Reflections from breakout groups and discussion  

12 Nov  

Session 2 

Lead :  Wataru YANASE (JMA) 

Rapporteur : TBD 

00:00-00:25 UTC  

Definition of subtropical cyclone  

John Beven (NOAA)  

00:25-00:50 UTC  

Cyclone Alfred: Subtropical-to-Tropical Transition and Forecasting Challenges 

Craig Earl-Spurr (BOM)  

00:50-01:15 UTC  

Physical and operational implications of medicanes' physical definition  

Emmanouil Flaounas (HCMR)  

01:15–01:45 UTC  

Breakout Discussion   

01:35-02:00 UTC  

Reflections from breakout groups and discussion  

13 Nov  

Session 3 

Lead:  ParthasarathiMUKHOPADHYAY (IISER, Berhampur) 

00:00-00:25 UTC   

Exploring Cyclone Transitions in AI/ML Weather Models: Preliminary Results from WP-MIP  

Ron McTaggart-Cowan (ECCC)  

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  

Closed meeting by invitation 

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 

  • ParthasarathiMUKHOPADHYAY, Indian Institute of Science Education and Research (IISER, Berhampur), India 

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