<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by PresRDC:
How is the weather (in terms of temperature and precipitation) in late October?
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IME, fall is the most pleasent time of year in Beijing because the weather is nice and the polution is relatively tame. You might consider setting your dates based on the fall foliage there -- many of the popular Beijing attractions (Xiangshan in particular) are especially breathtaking amidst the backdrop of colorful leaves.