HELP!! Need ideas coolant overflow on a 9 degree morning

so i was on my way to work this morning and the jeep is running great. noticed that my temp gauge was climbing pretty fast considering it was 9 degrees outside. just as i am pulling off to the side of the road to see whats up it starts smoking horribly. it was boilover out of the radiator. i'm thinking that its either the thermostat or the water pump. i had already checked the antifreeze and i was good to -30 F. its a 2000 Classic 4.0. any and all ideas would be great. i'm going to pick it up later with a buddy's trailer and take it to his shop. sorry this is so long. oh and the jeep never overheated on the gauge it only got to 210. would the thermostat getting stuck closed cause this boilover to happen? thanks in advance for any help guys.

I think you right with the t-stat. If you hadn't check the anti-freeze I would say frozen rad but with -30 that should be cool. Did the heater work OK? If so your water pump would be ok for 9 deg weather. Besides water pumps impellers generally last longer then that as long as you keep the anti up to speck.
Sucks to over heat in this cold but it happens a lot more then most think.

ive been having heater issues with this thing all fall and winter. ive flushed the heater core a few times and was just getting ready to flush the rad and change out the thermo tomorrow anyway. but i have been getting at least luke warm heat. this morning there was no heat even when the temp was going up. thats one of the reasons i was suspecting the thermo being stuck closed not letting coolant flow to the core. i'm just trying to get a plan together for where i'm going to start. i'm thinking i'm going to flush the system and heater core again, put in a new thermo, and then get it up to temp and see if that solves it. then move on to the water pump if i need to. is there a sure fire way to check the water pump? besides making sure that the upper rad hose is hot?

Check the weep hole in the bottom of the pump (it's behind and below the pulley- kind of difficult to inspect on the truck, but if it's leaking there, it's done). Check for slop or noise- when I turned the pulley by hand, with the belt off, it sounded strange, and there was some side to side movement as well. There's quite a few threads on here about cooling systems, water pumps, et al. Try searching for related threads- just about anything you'd want to know on cooling or heating has been covered repeatedly. Should be able to find something to help you out. Good luck.

got the thing fixed ended up flushing everything and replacing the thermostat. i think it was a clog in the radiator that messed me up this morning because when i flushed it there were alot of sediments in it. got it to run clean by the time i was done though. on an interesting side note i went to replace the thermo took off the housing and there was nothing there. i'm guessing the previous owner had some overheating issues and took it out as a quick fix to trade it off? gotta wonder about somebody who won't even replace a $8 part.