is there a typical temperature for raw meat going into the smoker? Obviously meat out of the refrigerator at 40 deg is going to take longer to reach temp than 60 deg meat?
I concede to your reply... Perhaps I didn’t understand the question? BI'm going to respectfully disagree with BD. Lets clarify your reason for asking the question. Are you concerned about the 4 hour 40-140F safety window, or trying to calculate time until the meat is done?
If you are concerned about the 4 hour safety window, good question. Here's where physics is involved. You need to know three things: the weight of the meat, the temp of the meat, the ambient temp of the surroundings (kitchen or smoker). Cold meat will absorb heat faster the hotter the ambient temperature of the surroundings.
Lets say you have your smoker fired up to 225F (ambient temp). Given two pieces of meat of the same weight, There's only about a 20 minute difference between 40F meat and 60F meat reaching 140F, and that's the time it takes for 40F meat to reach 60F in a 225F smoker.
Now, how long does it take 40F meat to reach 60F in a 70F kitchen? The difference between the meat temp and the kitchen temp is only 30F, so there is a LOT less heat energy available for the meat to absorb. For a roast as small as 3 lbs, it can take up to two hours for the meat to warm up to 60F, a big portion of your safety window.
I often fire up my smoker, then go in and prepare my meat. My fridge keeps meat at 34-36F. The way I'm loading my smoker these days, it can take up to 90 minutes for the smoke to start showing hints of blue and I load the meat. We keep our house at 65F in the winter, 75F in the summer. Even after 90 minutes on the counter, the meat is often no warmer than 41-42F when I put it in the smoker. 8-10 lb butts and 15 lb briskets are often no warmer than 38-39F after 90 minutes on the counter, no where near room temp.
I've heard published and TV personalities say meat from the refrigerator will come up to room temp in an hour. Absolutely NOT true. Don't believe me, test it. Even a small steak of 8 oz will be no warmer than 50-55F in an hour. I fixed four chuck-eye steaks tonight on the kettle, 3.8 lbs total, a little less than a pound each. They were 34F when I took them out of the fridge. 39F when I was ready to put them on the Kettle about a half hour later.
Meat reaching room temp in an hour is an old wives tale.