A heavy hailstorm hit São Paulo, Brazil on 18 May, blanketing the city with marble-sized hailstones.
The Metop-B AVHRR composite image shows high cloud generated by a westerly flow of humid warm air when reaching the colder air in the São Paulo region. The instability was, however, stronger than usual in autumn.
The Meteosat-10 composite animation shows the shade early in the morning and lower cloud near the terrain.
After the hail, haze was produced by intense evaporation of the ice corns, a process which is estimated to last for a couple of days, given the cold original temperatures of -20 °C in their core.
Brazil's Sao Paulo turned white by freak hailstorm, BBC news
Brazil Hailstorm Shocks Sao Paulo, The Weather Channel
Globo.com news story (in Portuguese)
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