The formula to convert Celsius to Fahrenheit is:

°F = (°C × 9/5) + 32

Substituting °C = 39 into the formula, we get:

°F = (39 × 9/5) + 32

= (351/5) + 32

= 70.2 + 32

= 102.2°F

Therefore, 39 Celsius is equal to 102.2 degrees Fahrenheit.