It can get slightly bumpy in the back when flying in the tropics, but these wide bodied long haul jets seem to do OK. Local flights in 737s are a bit more bumpy in the back, but don't know whether thats because they are smaller or because the local flight crew are more confident around storms than those visiting from afar, so get closer.
But for real turbulence on
scheduled flights you cannot beat the 19 seat turbo-props that shuttle you from Denver to the ski-towns over the continental divide. Those things take off into the nastiest winter blizzards and head west, straight for the 14000ft high wall called the Rockies 40 miles away, crossing at the MEA a few thousand feet above the peaks. Once you have had your bones broke going up on the lee side, they come down into the valleys on the west and start hunting for the localiser on some untowered airport with some automated weather system - or even worse a ramp-rat with a radio
More often than not the weather is below minimums and we get to hold a few thousand feet above the ground at some VOR, being thrown around like a rag doll in some horific snow storm, the boots on the wings working like the clappers, pilot doing mental gymnastics calculating his inbound leg.
Half the plane are saying prayers to a new found god, the other half are crazy Texans on their ski-holiday, whooping and hollering like they are on the back of a wild bull that's just had the rope around it's nuts tightened hard.
The the skipper comes on saying 'Well folks, sorry about the ride back there, just an average days work here in Colorado, looks like there is a break in the weather and we're going for it'!
Plane breaks off and slams into some nasty wind shear, up and down she goes, total white out through the windows, teeth falling out, seat belt about to snap and all of a sudden it's clear and a few seconds later a lovely greaser of a landing.
Captain makes sure he is standing at the aircraft door before the seat belt sign is turned off, big grin on his face, and as we all stagger off he is high-fiving everybody.
If they cannot get in after half an hour holding they head back to Denver and that's when it gets real scary, cos that's when they say the only way you will get there tonight is on the bus....