Ok the rain has come and gone, and I ended up going with the umbrella. I didn't have brick close by, so I stood out under the umbrella next to the smoker until the rain passed (luckily no lightning was in the area). The rain got to the smoker before I did, so the temperature of the smoker dropped just a hair under 200 at the lid. I opened all vents, and stirred the coals to get the temp moving in the right direction.
I'm not sure if this is common, but all three butts seem to be warming up at a faster pace than I am used to. I put them all on about 4 1/2 hours ago, and have maintained a temp between 200 and 240 in that time. Before trimming the fat away, all butts weighed around 7.5 to 8 lbs. So now 4 1/2 hours later I have temps avg. around 170. I'm used to 10 and 12 hour smokes. Should I be concerned or is this nothing to worry about? Maybe I'm hitting a stall period in my cook. Also, I like to pull at about the 200 mark.
I won't be serving the butts until tomorrow.