O evento ocorreu hoje, durante a passagem de uma intensa frente fria. O fenômeno desenvolveu-se em uma área classificada pela PREVOTS com nível 3 de severidade para tempestades, indicando condições favoráveis à ocorrência de fenômenos meteorológicos severos.
Potential for another outbreak in South America tomorrow, which could possibly be similar to the outbreaks last month in the same general area. Last month's outbreaks produced the high-end F2 in Santa Fe Argentina, and the F3+ in Girua Brazil.
source: https://www.rawinsonde.com/ASTORP_SAM/SPC_hazards.html
Edit: the departments in Uruguay at the highest risk includes Artigas, Rivera, Cerro Largo, Tacuarembó and Salto. The State effected in Brazil is Rio Grande de Sul (mostly in the southern half). Other places effected but in not as high of a risk is Corrientes and Entre Rios provinces in Argentina, and extreme southern Paraguay. All of these regions are at risk for significant winds and hail alongside a strong tornado threat. Make sure you are weather aware in these regions tomorrow and have action plans in place. If you have friends or family in these region let them know of the threat.