This will be the first cold front to hit us this season as they move back down from the north. the last we saw of them was the mei yu back in early June. Technically, this is a cold and warm front: the pointy bits being the cold front and the rounded ones being the warm front. cold fronts bring colder weather obviously, more rain, and different wind. the mei yu fronts are called 'stationary fronts' coz they move slowly, but these autumn-winter kinds move much quicker.
This from: http://www.weatherquestions.com/What_are_fronts.htm
"Fronts are the boundaries between air masses of different temperature. If warm air is moving toward cold air, it is a “warm front”. These are shown on weather maps as a red line with scallops on it.

If cold air is moving toward warm air, then it is a “cold front”. Cold fronts are always shown as a blue line with arrow points on it."