Well her hottest is hot enough to light paper and dry leaves on fire.  Paper ignites at about 480F.  You can burn skin at about 176F, which is only about 80 degrees hotter than a normal human's body temperature(ha, "only"), and is about 300 less than her established high.  So I think a waking range of 180-480(depending on the time of day) is reasonable.  

Of course, I'm noting that I only mentioned her as being "impossible for others to touch during a certain part of the day," where this scale makes her impossible to touch basically all of the day.  I think I'll scale it down a bit, but I'll let her burn Audrey just this once, to demonstrate her power.  

Let's say she's ranging from 130(probably uncomfortably hot to touch for extended periods) to that same 480.  And when she's asleep, she's closer to someone who just has a fever.