Key these data to the animation. Winds shift to south at 00Z (6pm CST) with pressure drop as low pressure starts to make itself felt. Notice the sharp rise in temperatures at 05Z (11pm CST) as the southerly winds really kick in -- temps rise throughout the night.

On the next two charts note the continuous drop in pressure and the continuous backing of the winds as the system moves into and across southern Wisconsin. Temps hold steady and rise somewhat throughout the day and evening (careful of change in temp scale!).


Here the system has passed (pressure is rising) -- after a heavy snowfall -- and winds have backed to northerly -- giving us a sharp decline in temperatures.