Interior low temperatures dipped into the 50 below range again today, as a cold snap that began Monday, deepened across the interior. Among the coldest readings this morning were minus 55 at Eagle and 54 below at Ft. Yukon. A strong inversion has kept hilltop temperatures in the 10 to 15 below range, while sinking the deepest cold into valleys. The Fairbanks bowl has also suffered from accumulated emissions.