Take a look at the following time-series plots, and see if you can figure out whether the storm is tropical or extratropical. If you thought this was a tropical cyclone, you are correct. Also, notice the 1-hour lull in winds flanked by abrupt peaks on either side that marks he eye wall. Tropical systems are often small compared with extratropical ones. No evidence is shown for any fronts.
Fronts are zones of temperature contrast accompanied by wind shifts and pressure kinks.
The wind directions blow constantly from the NE for 15 hours before the eye strikes. Then, they blow from SW for 18 hours after the eye passes. Now, take a look at the following time-series plots. This is an extratropical or winter storm. Perhaps the colder temperatures give the answer away, but other, more fundamental reasons exist.