Possible Clues:

• Humidity factors into it
• *Wind chill factor relative
• Measurement known as "apparent temperature" (... letters 4-5 + 7-8)
• Measure of temperature plus humidity
• "Feels like" figure that combines temperature and humidity
• Summer weather measure (In this clue's answer, see the first 2 letters + the last 1)
• "Feels like" weather calculation
• 'Feels like' weather calculation
• Wind chill factor's opposite