Sasha Obama — in high-cut jean shorts — bears up under the brutal midday heat yesterday as she shops in Soho.

The president’s youngest daughter, who celebrated her 12th birthday two weeks ago, was joined by friends — and a 20-person security detail — for her stroll.

The heat wave should last two more muggy days, with high temperatures in the low 90s. before a cool front arrives from the West, forecasters said.