For almost a week now, I've been having consistent lag spikes lasting 1-3 seconds. They usually occur every few minutes, if not more frequently.

ISP:
Time Warner

Type of Internet Connection:
Cable

Internet Connection Speed:
50 mbps

I did a few tracerts to help with the issues. Here are two examples:
C:\Users\>tracert 199.91.189.74

Tracing route to 199.91.189.74 over a maximum of 30 hops

1 <1 ms <1 ms <1 ms [192.168.1.1]
2 44 ms 22 ms 18 ms cpe-173-89-136-1.new.res.rr.com [173.89.136.1]
3 31 ms 28 ms 27 ms tge7-1.nenhwi0501h.midwest.rr.com [24.164.234.161]
4 18 ms 19 ms 19 ms be34.milzwift01r.midwest.rr.com [65.31.113.52]
5 23 ms 19 ms 19 ms bu-ether18.chctilwc00w-bcr00.tbone.rr.com [66.109.6.206]
6 18 ms 18 ms 18 ms 0.ae0.pr0.chi30.tbone.rr.com [66.109.1.76]
7 * * 20 ms lag-8.ear2.Chicago2.Level3.net [4.68.111.33]
8 40 ms 39 ms 38 ms ae-10-10.car2.Montreal2.Level3.net [4.69.153.86]
9 39 ms 41 ms 40 ms ae-10-10.car2.Montreal2.Level3.net [4.69.153.86]
10 40 ms 41 ms 40 ms ORMUCO-COMM.car2.Montreal2.Level3.net [4.59.178.74]
11 41 ms 41 ms 41 ms 192.34.76.10
12 39 ms 40 ms 41 ms 199.91.189.242
13 41 ms 41 ms 41 ms 199.91.189.74

Trace complete.

C:\Users\>tracert 199.91.189.74

Tracing route to 199.91.189.74 over a maximum of 30 hops

1 <1 ms <1 ms <1 ms [192.168.1.1]
2 40 ms 30 ms 29 ms cpe-173-89-136-1.new.res.rr.com [173.89.136.1]
3 31 ms 21 ms 31 ms tge7-1.nenhwi0501h.midwest.rr.com [24.164.234.161]
4 17 ms 19 ms 23 ms be34.milzwift01r.midwest.rr.com [65.31.113.52]
5 23 ms 22 ms 27 ms bu-ether18.chctilwc00w-bcr00.tbone.rr.com [66.109.6.206]
6 19 ms 21 ms 19 ms 0.ae0.pr0.chi30.tbone.rr.com [66.109.1.76]
7 * * * Request timed out.
8 40 ms 135 ms 108 ms ae-10-10.car2.Montreal2.Level3.net [4.69.153.86]
9 41 ms 42 ms 40 ms ae-10-10.car2.Montreal2.Level3.net [4.69.153.86]
10 41 ms 41 ms 39 ms ORMUCO-COMM.car2.Montreal2.Level3.net [4.59.178.74]
11 41 ms 43 ms 38 ms 192.34.76.10
12 38 ms 54 ms 41 ms 199.91.189.242
13 41 ms 42 ms 41 ms 199.91.189.74

Trace complete.

C:\Users\>tracert 199.91.189.74

Tracing route to 199.91.189.74 over a maximum of 30 hops

1 <1 ms <1 ms <1 ms [192.168.1.1]
2 11 ms 23 ms 13 ms cpe-173-89-136-1.new.res.rr.com [173.89.136.1]
3 21 ms 34 ms 24 ms tge7-1.nenhwi0501h.midwest.rr.com [24.164.234.161]
4 22 ms 18 ms 19 ms be34.milzwift01r.midwest.rr.com [65.31.113.52]
5 25 ms 23 ms 35 ms bu-ether18.chctilwc00w-bcr00.tbone.rr.com [66.109.6.206]
6 21 ms 17 ms 19 ms 0.ae0.pr0.chi30.tbone.rr.com [66.109.1.76]
7 * 18 ms 34 ms lag-8.ear2.Chicago2.Level3.net [4.68.111.33]
8 41 ms 40 ms 40 ms ae-10-10.car2.Montreal2.Level3.net [4.69.153.86]
9 38 ms 38 ms 40 ms ae-10-10.car2.Montreal2.Level3.net [4.69.153.86]
10 40 ms 41 ms 41 ms ORMUCO-COMM.car2.Montreal2.Level3.net [4.59.178.74]
11 42 ms 40 ms 41 ms 192.34.76.10
12 41 ms 41 ms 40 ms 199.91.189.242
13 * * 2670 ms 199.91.189.74

Trace complete.