Las Condes in November

March through May gives you perfect weather — warm days, cool evenings, and the Andes are crystal clear after summer's smog clears out. September through November works too, as spring brings blooming jacarandas along the main avenues. Summer (December-February) gets hot and smoggy, though the rooftop bars make it bearable. Winter isn't terrible — think San Francisco cold rather than New York cold — but the mountains disappear behind gray skies for weeks. Here's the insider tip: avoid the first two weeks of February when wealthy Chileans return from beach vacations and everything gets crowded. Business travelers should know that January is dead quiet as most offices close for summer holidays. The shopping is best during the end-of-season sales in March and August.