To take advantage, start your search at Google Flights, where it's easy to compare travel dates and find the cheapest fare. Then take your desired flight over to Momondo and enter the dates of your flight there. You may find that you trim between $5 and $40 off the price of the exact same flight by searching through Momondo.
Cities where you're going to find good deals right now include Boston (Chengdu for $466), Charlotte (Chengdu for $531), Chicago (Guangzhou for $447), Detroit (Guangzhou for $492), Las Vegas (Chengdu for $437), Los Angeles (Chengdu for $450), New York (Guangzhou or Shenzhen for $467), Philadelphia (Chengdu for $478), Pittsburgh (Chengdu for $478), Raleigh (Chengdu for $477), San Diego (Guangzhou for $478), San Jose (Guangzhou for $467), Washington DC (Chengdu for $492), and Vancouver (Chengdu or Shenzhen for $575 CAD).
This list is by no means exhaustive. All of these cities have deals to multiple destinations and you'll undoubtedly find deals out of other cities. But it's worth doing it soon. Prices change rapidly and the best deals may be gone.
[h/t Scott's Cheap Flights]
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