The mercury is dropping as Minnesotans prepare for the coldest weather of the season so far. Temperatures are already in the single digits below zero in many areas of northwestern and west-central Minnesota and in the single-digits above zero for the rest of the state — except for the metro, east-central, south-central and southeast Minnesota — but expect temps to drop off there also. The Weather Service says zero to 15-below tonight with wind chills 15- to 30-below. Tuesday’s highs will be only five-below in the north, five to 10 above in the south, and more double-digit below zero readings expected Tuesday night. A gradual warm-up is expected going into the weekend.