Emp about to molt, need advice.

So, I've had my Emp for about 3 1/2 months now, and it seems that he's about to molt. He is getting very round and has been outside of the den for 2 days now. I have confirmed that it is a male, so it's not pregnancy. I live in Alaska, which has very dry air, so I get 60ish% humidity at best (according to the hydrometer, at least). It doesn't seem to affect him, but the substrate is pretty dry. Should I be spraying it each day? If not, what else should I be doing? This is my first time dealing with a molt, and I really don't want to make a mistake. Thanks in advance.

None of mine have molted yet, but I assure you, misting it helps alot to raise the humidity, or at least getting the soil moist. they LOVE moist soil, not drenched, or wet, just moist.

i've been told 60-80%, even upwards of 90%, especially when there are babies. so make sure you keep it covered and mist it a bit. watch your hygrometer, and get it somewhere near 80-90 for a molt.

Pour some water onto the substrate, don't spray as it isn't very long lasting and gives less effect.

what hydrometer is it? digital or stick on? only digital ones are accurate and the stick on ones arent even a good indication at all. dump water on the substrate, make sure the heat is good so that its nice and humid, make sure it is always damp, even when it has molted it will want damp soil.
any idea what instar it is? can you get a picture? its normally easy to tell if its not adult by the color of the stinger.
how often does it eat? it could just be fat.

Thanks for the replies. I actually do pour water into the substrate, but as I said, we have dry air, and it doesn't seem to get quite as humid in there as you would think. I have a stick on Hydrometer, though, so it may be off. He hasn't eaten in 2 weeks, so I don't think he's just getting fat. I don't think that I will be able to get up a picture (although I will try), and I have absolutely no clue what instar means. If it helps at all, he has a red stinger (mild, not dark or light) and is about 5 inches. He was about 3 inches when I got him and had a more white stinger, which means that he is growing, but as to whether or not it's a molt, I guess I'm not sure. I'll keep you updated.

how far off do non digital hygrometers run?

as much or little as they want to. you may as well just look at how much water is on the glass, it will be more accurate.
instar = number of moults. ie. 1st instar = newborn, and 5th instar = subadult (in emps).
a picture in the right light to show accurately what colour the stinger is and how big the scorp is (something to compare to like a ruler).