The forecast for Tuesday and Wednesday calls for highs pushing into record-setting territory in the mid-80s, according to the National Weather Service.
Normal temperatures for Oct. 17 in the Harrisburg region are a high of 64 and a low of 43. The record high was 86 in 1908 and the record low was 31 in 1937, according to AccuWeather.
Tuesday and Wednesday are each expected to be sunny, with lows in the low-60s on Tuesday night and high-50s on Wednesday night.
Prior to that, Monday is expected to be cloudy with with a high near 78 followed by gradual clearing.
It will start to cool down on Thursday, which is expected to be sunny with a high of about 77.
On Friday, when there will be a 50 percent chance of rain, a high of about 64 is expected, with the temperature dropping into the lows 50s at night.
The weekend forecast calls for cloudy days on Saturday and Sunday with highs in the low 60s and temperatures falling into the low 50s at night.
A cold front moving in over the weekend could result in the first snowflakes of the season in some parts of the northeast, according to AccuWeather.