PORTLAND -–The city passed a 31-year-old high temperature record for July 19 by reaching 95 degrees shortly after 4 p.m., the National Weather Service said.

The temperature remained at 95 at 5 p.m., but wasn’t expected to climb further, said Michael Cempa, a meteorologist with the National Weather Service.

Cempa said Portland was the hottest spot in the state Friday. He said the heat index, which combines heat and humidity levels, hit 103 on Friday afternoon.

The high temperature Friday made it the first record-setting day for high temperatures this month, Cempa said, but there have been five record-low temperature marks set – for the warmest overnight lows.

Cempa said one more hot sticky day is expected during the current heat wave, with temperatures expected to hit around 90 degrees Saturday with continued high humidity. He said a cool front will move through Saturday night, possibly touching off thunderstorms, with the high Sunday expected to top out around 80 degrees, with much lower humidity.

Lows Sunday night, he said, should drop into the 50s in southern Maine and possibly into the 40s in the northern part of the state.

Scarborough Downs canceled its live harness racing Friday after the heat index reached 100 at the track, said Stephen Cobbett, the director of operations.

Cobbett said the track consults with veterinarians, horse owners and state officials when the heat index tops 100 and calls off racing if it’s determined that it might be detrimental to the horses’ health. 

Cobbett said the heat index topped out at 105 at the track Friday.

Betting on simulcast races from other tracks around the country continued in the Downs’ air-conditioned clubhouse, he said. Officials will make a determination about racing Saturday in the afternoon, although he said the forecast is for the extreme heat to break overnight.

Under state rules, Cobbett said, Scarborough Downs can add a day of racing to make up for one lost due to weather. He said racing currently take place on Thursday through Sunday afternoons, but the Downs drops back to three days of racing – Friday, Saturday and Sunday – after next week.

The record-setting heat Friday comes after five straight days of temperatures between the mid-80s and the low 90s in Portland. The unusually long stretch of hot weather is part of a regional heat wave that has pushed power demands to near-record levels in New England. The operator of the regional grid has asked customers to conserve electricity, such as by raising the temperatures on air conditioners.

Health and emergency response officials have warned that the heat can be dangerous, especially for the elderly, the very young and those with underlying illnesses. Vulnerable people are advised to stay in air-conditioned buildings and stay hydrated.