A strong and moist Pacific jet stream will dive southeast across Wyoming this weekend bringing heavy snow to all of Wyoming’s major mountain ranges  through early Sunday. Already over a foot of snow has fallen in portions of the Snowy Range Mountains. Additional snowfall through Sunday over Wyoming’s major mountain ranges will be 10 to 24 inches. Wyoming’s mountain snowpack should increase by Sunday, especially in the Platte River drainage. On the plains, light snow will develop in northern Wyoming Saturday and will spread into southern Wyoming late Saturday night and Sunday morning. Much colder temperatures will be found statewide on Sunday.