Ion Petroianu, VA3NOI
The load current is way lower, about 0.15A (what the current draw on the +5V line is).
That results in a power dissipation of 1.25 to max 1.35W.
TO-220 package has a thermal resistance Jonction to ambient in free air of 23.9 C/W
1.3W * 23.9 C/W = 31 C, which is very close to what I have measured on my board