It's good to hear it may not be all gloom and doom. Error on the side of caution and keep him warm and dry. If he's eating feed him food that has high water content such as fish or worms to help keep him hydrated.

It's very easy for a cold (upper respiratory virus) to open the door for bacterial pneumonia. I nearly lost my own life that way, I thought I just had a cold. Turns out I did, but it quickly turned into a life threatening situation when bacteria took advantage of the taxed immune system.

I tend to think that anything above 90 degrees is a bit excessive though. Anyone else?

These things can be caused by excessive heat or lack of a gradient too. Snakes need to thermoregulate you know. Ideal temperature is not ideal if it's uniform throughout the enclosure. I know that when I was keeping/breeding sceloporous (spiny) lizards, they would develop nasal "colds" if they didn't have sharp gradients, and/or a drop in temperature at night. Uniform heat, even in the ideal range wasn't good for them. they needed a cooler area, a hotter area, and drop at night. The colds (runny, bubbling noses) stopped when I started doing that.