World weatherwatch: Peru’s saint of storms brings salvation to cities and ski slopes

Seasonal storms that blow up on the Peruvian coast at this time of year are named after St Rosa

In August 1615, a Dutch pirate fleet under Joris Van Spilbergen threatened the city of Lima. According to legend, a nun called Sister Rosa, whose original name was Isabel Flores de Oliva, prayed for deliverance. A tremendous storm blew up just as the pirates were sailing in to sack the city and scattered their fleet.

The storm was hailed as a miracle, and Sister Rosa became the first person born in the Americas to be canonised. She is patron saint of embroidery, gardening, the Americas, and the city of Lima. The seasonal storms that blow up on the Peruvian coast at this time of year are known as the Tormentas de Santa Rosa or Saint Rosa's storms. These traditionally occur 15 days either side of the saint's day on 30 August.