SENSITIVITY STUDY OF BRAMS FORECAST IN AN ORGANIZED MESOSCALE CONVECTIVE EVENT

NICOLINI, MATILDE; GARCIA SKABAR, YANINA; VIDAL, LUCIANO; SALIO, PAOLA VERÓNICA

Palma

Conferencia; 6th European Conference on Severe Storms; 2011

European Severe Storms Laboratory- Universitat de les Illes Balears

Heavy rainfall and other severe phenomena related to deep convection and their forecast is a major problem in different geographical regions. Subtropical South America (including La Plata basin) is particularly affected by large and intense mesoscale convective systems (MCSs) within which severe events develop specially during the warm season. One of the main objectives is to progress in the forecast of these intense events in order to reduce related damages.During early morning of January 12, 2010 an extended convective line developed in association with a cold front that propagated over the central and northern part of Buenos Aires Province, Argentina. Related storms produced severe winds (reported gusts exceeding 30 m s?1) in different locations around the city of Buenos Aires, causing material damage and even lost of lives.Numerical forecasts of the case study were performed using the Brazilian model Regional Atmospheric Modeling System (BRAMS), reaching a horizontal resolution of around 2km. In the present paper, model forecast performance was evaluated against measurements from radar, satellite estimations of precipitation and surface observations available in the region. The sensitivity to different initial conditions, horizontal and vertical resolution and settings on cloud microphysics scheme are addressed and discussed in order to maximize the BRAMS forecast potential for this particular case.