Mean annual temperature: 100
Mean temp. of the wettest quarter: 98.6
Mean temp. of the driest quarter: 35
Mean temp. of the warmest quarter: 100
Mean temp. of the coldest quarter: 96.8
A temperature reading in the 100th percentile means it is higher than 100% of the other temperature readings; in the 99th percentile means it is higher than 99% of the other readings, and so on down.
Source: Monahan WB and Fisichelli NA (2014) Climate Exposure of U.S. National Parks in a New Era of Change. National Parks Service.