Hello fellow smokers. I recently purchased an 18" Weber Smokey Mountain vertical bullet smoker, and after seasoning it and completing 3 smokes (ribs, thighs, and beer can chicken), have attempted my first smoked pork shoulder butt roast. I got a 4.75 lbs bone-in butt roast with a fat cap, coated it with spicy yellow mustard, then rubbed down with a pork rub, and left overnight in the refrigerator. This morning, before work, I set up my WSM using minion method, with combination hickory/apple wood chunks. At 225, I placed the roast on the top rack, estimating cook time to be appx. 7- 7.5 hrs. I used my new wireless digital thermometer (single zone, multi-sensor CharBroil), inserted the probe into the roast making sure that it didn't go near the bone, covered the lid, and left to work. Bottom vents are 65-75% open, top is at 50%, temp is stable 225. Here is my concern: in 1 Hr and 15 min, temperature inside the roast went up from 37F to 111F at the coldest setting, and 132 at the highest. WSM's dome thermometer still showed steady 225. I am worried that the internal temp is rising much faster than I expected and the roast will burn up before I get home. I plan to go back and check on it in about 3 hrs. Do you think it is cooking much too fast? Any thoughts/ suggestions? Thank you very much.