EGU25-18235, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-18235
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Assimilation of Rainfall and Total Lightning Data for Nowcasting Torrential Rainfall During Summer Thunderstorms in Japan
Debrupa Mondal1, Yasuhide Hobara1,2, Hiroshi Kikuchi2, and Jeff Lapierre3
Debrupa Mondal et al.
  • 1Department of Computer and Network Engineering , University of Electro-Communications, Tokyo, Japan (debrupamondaljam@gmail.com, hobara@ee.uec.ac.jp )
  • 2Center for Space Science and Radio Engineering, University of Electro-Communications, Tokyo, Japan (hkikuchi@uec.ac.jp)
  • 3Earth Networks, Germantown, MD 20874, USA (Jeff.Lapierre@aem.eco)

Recently, detailed spatio-temporal analysis, using X-band multi-parameter radar-derived 3D volume scan and total lightning data in Japan, have revealed the peak in-cloud (IC) lightning occurs ~10 mins before maximum ground precipitation for individual cells of a summer thunderstorm (TS) producing torrential rain. This study investigates the potential of utilizing the total lightning data for monitoring and short-term prediction of torrential rain during three summer TS events causing heavy rainfall over Japan: an isolated TS, a TS possessing a merging of two cells, and a splitting TS cell. We construct simple linear regression models using (1) only ground precipitation volume (PV) and (2) a combination of ground PV and IC pulse rate. These models are continuously updated with the latest observations of IC and ground PV values to predict the one-step and multi-step ahead values of ground rainfall. We demonstrate a promising approach for short-term prediction of ground rainfall, by simultaneous application of the current and historical data of IC pulse rate and PV, which showed high accuracy (cross-correlation coefficient between observed and predicted PV was 0.84~0.94).

How to cite: Mondal, D., Hobara, Y., Kikuchi, H., and Lapierre, J.: Assimilation of Rainfall and Total Lightning Data for Nowcasting Torrential Rainfall During Summer Thunderstorms in Japan, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-18235, https://doi.org/10.5194/egusphere-egu25-18235, 2025.