Allow me to give some perspective on these matters:
-read the first several pages of the other flight delays thread in order to get up to speed on summer time flying
-for the first part of this summer, every single one of my flight delays (i.e. ALL flights) had plausible weather related excuses
e.g. see here: http://www.usatoday.com/story/travel...jing/30774143/
-but, yesterday, the weather was fine in Shenzhen, Shanghai, and all points in between... and, I still got hit with a 2.5 hour delay

While I was roasting on the tarmac in Shenzhen, I checked out the Shanghai airport website, and noticed that all flights to/from the south and west were basically on hold... while everything else was not.

This leads me to suspect (and, only suspect because I have no proof) that the Nanjing PLA has started to perform its annual summer training exercises, now that the weather is nice.

For data purposes:
-9C8918, August 2
-SZX-SHA
-1025a departure; 250p (actual) arrival
-boarding was delayed by 1.5 hours
-+1 hour on the tarmac
-I'm really glad that they didn't subject us to the entire 2.5 hours on the tarmac, btw