Multi-scale interactions between moist-air flow and deep convection during HyMeX IOP15a heavy precipitation event

Keun-Ok Lee (1) , Cyrille Flamant (1) , Véronique Ducrocq (2) , Julien Delanoë (3) , Jean-Christophe Raut (1) , Patrick Chazette (4) , Nadia Fourrié (2) , Laurent Labatut (2) , Olivier Bock (5)

1 TROPO - LATMOS
2 CNRM - Centre national de recherches météorologiques
3 SPACE - LATMOS
4 LSCE - Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette]
5 LAREG - LAboratoire de REcherche en Géodésie [Paris]

Heavy precipitation event (HPE) recording the rainfall accumulation greater than 130 mm occurred during IOP 15a in the northern Spain region. With the aim to clarify the characteristic, transport, and role of water vapour patterns to the HPE, the intensive field observation was successfully carried out. Using the observational dataset of SAFIRE/ATR42 airborne water vapour lidar LEANDRE2, ground-based lidar WALI, ground-based GPS network, rain gauge network, and SEVIRI satellite, together with AROME-WMED data, in this study, we investigate the multi-scale interactions between the moist-air flow and deep precipitation during IOP 15a. The analysis of AROME-WMED fields showed that the lowlevel wind convergence of easterlies and south-easterlies with 10−12 m s-1 wind speed was continued in the north-eastern coastal region of Spain (Catalonia, CA) during 19-20 October 2012. With the low-level south-easterlies, the supply of high mixing ratio of water vapour greater than 14 g kg-1 from the northwestern Mediterranean Sea to the CA region was continuously captured. In this environment, the surface rain gauge network recorded the rainfall in the CA region, steadily from 04 UTC on 19 October to 22 UTC on 20 October. During the same period, the ground-based GPS (2.0°E, 41.4°N) steadily recorded the relatively-large amount of integrated water vapour of 36−43 kg m-2. The SAFIRE/ATR42 travelled the upstream of the HPE two times: AS52 from 0954 to 1256 UTC, and AS53 from 1414 to 1519 UTC on 20 October. As it approached to the upstream of HPE, a layer having the water vapour greater than 10 g kg-1 ascended from below 0.4 to 1.1 km; simultaneously, the maximum water vapour increased up to 14.5 g kg-1. These well-captured low-level water vapour characteristics in the upstream of HPE during IOP 15a and its dynamical interaction with the HPE development will be introduced at the conference.

Domains: Meteorology; Atmospheric and Oceanic Physics [physics.ao-ph]

Keun-Ok Lee, Cyrille Flamant, Véronique Ducrocq, Julien Delanoë, Jean-Christophe Raut, et al.. Multi-scale interactions between moist-air flow and deep convection during HyMeX IOP15a heavy precipitation event. 9th HyMex Workshop, Sep 2015, Mykonos, Greece. ⟨insu-01206836⟩