The Midwest and Northeast continues to swelter under a record-breaking heat wave. Temperatures in Newark, N.J. Reached 108 degrees yesterday, the highest ever recorded, while Washington and Baltimore hit 105. New York City hit 104 degrees, two degrees short of its all-time high, but the humidity made it feel like it was 113. Dozens have died in the heat wave, including an 18-year-old landscaper Thursday night in Lousiville, Ky., where temperatures reached 110. The electrical grid that serves 13 mid-Atlantic states set an all-time record for power usage Friday, with blackouts in some areas.