Rapid Volumetric Growth of Misocyclone and Vault-Like Structure in Horizontal Shear Observed by Phased Array Weather Radar

Abstract

The present paper reports a sub-minute scale growth of a misocyclone and vault-like structure in a horizontal shear environment observed by a phased array weather radar (PAWR). Between 0756 and 0801 Japan Standard Time on 25 August 2013, dual radar synthesis shows a signature of significant low-level convergence at 0.6−0.8 km above sea level (ASL). PAWR data show a coincident rapid growth of a misocyclone with top altitude increasing from 1.2 to 1.8 km ASL in two minutes. A small vaultlike structure with the maximum height of 1.3 km is formed following to the development of misocyclone with a delay time of about two minutes. One possible explanation is the role of vorticity stretching associated with horizontal shear instability. Fast and volumetric seamless observation of such a small spatiotemporal-scale phenomena opens up a way to progress our understanding of misocyclone that is of importance for convection initiation and severe weather phenomena.(Citation: Adachi, T., K. Kusunoki, S. Yoshida, H. Inoue, K. Arai, and T. Ushio, 2016: Rapid volumetric growth of misocyclone and vault-like structure in horizontal shear observed by phased array weather radar. SOLA, 12, 314−319,

High Temporal‐Spatial Resolution Observation of Tornadogenesis in a Shallow Supercell Associated With Typhoon Hagibis (2019) Using Phased Array Weather Radar

“…Additionally, we eliminated spiked noise using a three‐dimensional median filter of size 5 × 5 × 3 in range, azimuth, and elevation, respectively. From the lowest and highest velocity peaks, we calculated physical parameters such as the radius, rotational velocity, and radial velocity of a pseudovortex (Adachi et al, 2016).…”

The SOLA Award in 2016

“…I am pleased to announce that The SOLA Award in 2016 is going to be presented to the paper by Dr. Toru Adachi et al, entitled with "Rapid volumetric growth of misocyclone and vault-like structure in horizontal shear observed by phased array weather radar" (Adachi et al 2016). This study is highly evaluated in demonstrating an observational evidence that the structure of misocyclones rapidly changes within a few minutes.…”

Analysis of the Tornadic Debris Signatures of the Ichihara Tornado in a Typhoon Environment Using Two Operational C-band Dual-Polarization Weather Radars

“…As the tornadic vortex parameters, we used the radius and rotational velocity (Vrot) of the pseudo-vortex calculated from the lowest and highest velocity peaks of the Doppler velocity fields (Adachi et al 2016;Adachi and Mashiko 2020). In this study, the tornadic vortex parameters were derived only from PAWR data.…”