The hottest day in several years occurred yesterday, scorching long-standing records around the region.

In Allentown, the temperature Friday reached 104 degrees at 3:42 p.m. That broke an 85-year-old record record of 101 degrees.The 104 reading was just one point shy of the hottest day ever recorded in Allentown, which was set on July 7, 1981.The heat wave, now almost a week old, is expected to continue through at least tomorrow, the National Weather Service says.An excessive heat warning is in effect for tomorrow. Although the temperatures might not reach three digits, the heat index is expected to be over 100.There will be some slight relief Sunday as a cold front moves through the area, and this could spark some potent storms with periods of heavy rain.PPL said the high temperatures resulted in record demands for electricity Friday afternoon. Preliminary figures show the demand on PPL's system for the hour ending at 2 p.m. Friday was 7,622 megawatts. This topped the company's all-time high for summer peak demand of 7,554 megawatts, set on Aug. 1, 2006, as well as the all-time winter peak of 7,577 megawatts set on Feb. 5, 2007.PPL Electric Utilities transmission and distribution systems continue to deliver power without any notable problems."Our attention to maintenance and inspection, the increasing investments in our electric delivery system, and our system planning are really proving their mettle during this scorching week," said Gregory N. Dudkin, senior vice president of operations for PPL Electric Utilities. "Investing in reliability means we're prepared for the hottest days of summer and the frigid cold of winter. Our customers rightfully expect no less."Friday was just the sixth day this year that peak demand has exceeded 7,000 megawatts. Four of those six days occurred this week, with the others coming on June 6 (7,049 megawatts) and Jan. 24 (7,365 megawatts).Over the past 10 years, PPL Electric Utilities' average summer peak was 6,949 megawatts, so this peak was about 10 percent higher than the company's summer average.The only local problem reported was in Mahoning Township where a power outage occurred not from the heat but from a truck hitting a utility pole.Other cities where heat records were established on Friday included:• Reading, 106 (previous 101 in 1926);• Philadelphia, 103 (100,1957);• Mount Pocono, 94 (93, 1955);• Atlantic City, 105 (98, 1998);• Trenton, 106 (101, 1926).Although there is an excessive heat warning today, no records are expected to be broken.Today's record temperature in Allentown is 99, set in 1955; others include Mount Pocono, 91 in 1955; Reading, 99 in 1955, and Philadelphia, 99 in 1991 and 1978.On Sunday, temperatures are expected to reach the mid 80s.