Car Talk Puzzler

A man drives to work one fall morning and sees a sign that displays the temperature in both Fahrenheit and Celsius. While he's at work, a strong cold front moves through the city and the temperature drops like a stone. On the way home, curious to see how badly the temperature dropped, the man looks at the sign again. The temperature in Fahrenheit has dropped 36 degrees. But he notices that the temperature in Celsius is exactly the same as that morning. The man shakes his head and assumes that there was just a problem with the sign. There was in fact a small glitch with the sign.

What was the glitch with the sign and what were the temperatures from that morning and that afternoon?

Answers (highlight):
The minus sign on the Celsius temperature was burned out.
Morning: 50F/10C
Afternoon: 14F/-10C