Average Temperatures for Philadelphia. Philadelphia's coldest month is January when the average temperature overnight is 25.5Â°F. In July, the warmest month, the average day time temperature rises to 85.5Â°F.The driest month in Philadelphia is February with 2.74 inches of precipitation, and with 4.39 inches July is the wettest month.n July, the warmest month, the average day time temperature rises to 85.5Â°F. The driest month in Philadelphia is February with 2.74 inches of precipitation, and with 4.39 inches July is the wettest month.
1 A data set has three quartiles: the lower quartile, the median of the data set, and the upper quartile. 2  Median: The median divides a data set into two equal parts. 3  Lower quartile: Median of the lower half of the data. 4  Upper quartile: Median of the upper half of the data.
Quartiles represent the value for which 25% of the data is below (Q1) and the value for which 25% of the data is above (Q3). The Interquartile Range (IQR) is the difference between these two quartiles (Q3 â Q1 = IQR).