I'm with YJ, it's probably your ISP working overtime. I would also double check your connection speed. I travel for a living, so I play with the same laptop every time I play, but every week on a different network and the biggest variable to me is connection speed. At home I have a 100 Mbps connection, on the road I'm usually between 11 Mbps and 54 Mbps.
If you've never played with an 11 Mbps connection, I recommend doing it just once. Click reverse view, stand up, stretch the legs, check the weather, go to the bathroom, get a drink or maybe a snack, come back and it should just about be done.
Also, if you are playing on a public network, (like at a Starbucks) those are your high usage times.
-Long