B737 Captain reported a rejected takeoff at 140 knots after receiving a Takeoff Configuration warning.

Narrative

Pushed back from gate. Normal operations and engine start. OAT 30 C; TOW 153.1; Flaps 5; bleeds ON; anti ice OFF; reduced thrust 92.8 N1 for Runway XXL.Called for Flaps 5 and we ran the after start checklist. Trim was set to 5.04 degrees in the green band. Ran the Before Takeoff checklist 'to the line'; everything normal. We were #1 for takeoff so I asked for the Takeoff checklist below the line. First Officer ran it; and I depressed the Takeoff Config switch with no sound so the system checked good.Approaching Taxiway 1 at [Runway] XXL Tower called out landing traffic on a 5 mile final to XXL and cleared us or takeoff. We took the runway; First Officer pushed power to 40% N1; engines stable; with NO Takeoff Config warning. First Officer then pushed power to 85% N1 and selected autothrottles. First Officer stated 'check thrust' and as I put my right hand on the throttles I replied ' thrust set 92.8%'. Takeoff roll commenced with NO Takeoff Config warning. I then called out '100 knots'.Runway XXL is quite bumpy for the first 2;000 feet to be noted. Approaching 139 knots we got 2 horn sounds (cabin altitude horn sound) and a RED Takeoff Config warning light by my MFD. I then announced rejecting at 140 knots and disconnected the auto throttles while quickly pulling the throttles to idle. The speed brakes deployed and instantaneously RTO braking was activated. I deployed the thrust reversers to Max and let the autobrakes slow us down. As we were slowing First Officer called out '80 knots' and I started to stow the reversers and apply manual braking. I also told Tower that we were rejecting on XXL knowing that there was landing traffic behind us. I remember hearing the Tower instruct the aircraft to Go-Around. I should have had First Officer tell Tower that we were rejecting as I had briefed on our pre-flight checklist; so that's one thing I would change for myself.We came to a stop and First Officer made the 'Remain Seated; Remain Seated' PA announcement and I made sure to NOT set the parking brake as we began the QRC for an RTO event and went through that checklist. We called for a fire truck to come check the tires and brake temps to make sure that we could taxi if possible as allowed by Brake Cooling chart. First Officer and I at first misread the chart and thought we were in the warning temps. So I called Dispatch and Maintenance Control while First Officer held the brakes for me. After checking with Maintenance Control we corrected ourselves and learned that we were only in the caution zone and had to let the brakes cool for XX minutes before another takeoff was attempted. Takeoff weight 153.1; 0 sea level correction; 140 knots speed. Plus it would take 2 miles to taxi back; so add 10 more minutes. At this point once we were confirmed in the caution zone I set the parking brake. We waited on the runway for approximately 15 minutes while talking to Fire Captain; Tower; FA's; passengers; Dispatch; Maintenance Control to ensure everything was stabilized; and no injuries or damage to tires and aircraft. After that we taxied slowly to the parking [area] where we waited out our brake cooling time. One thing that I would change is to make a note in the brake cooling temp charts that it is ACCEPTABLE to exit the runway with hot brakes so as not to close down a runway for a long time. We had to talk to Dispatch and the Operations just to confirm that we could leave the runway prior to adhering to the brake cooling time limit. I remember seeing that info hidden somewhere in the FM; but I couldn't remember exactly the protocol. It would be helpful to have that info directly on the brake cooling chart.We waited out our brake cooling time in the parking area and had the Fire Captain check the brakes periodically with his FLIR gun. We talked to the passengers and FA's frequently so as to give them information and keep them in the loop. I turned OFF the seatbelt sign so passengers coulduse the restroom and retrieve cell phones to make calls. After waiting out our time; I talked to the passengers and FA's again; turned ON the seatbelt sign; and the Fire Captain gave us the OK to taxi. Then Ground let us taxi back to gate. We approached gate and of course a rain shower with lightning hits the field; so the ramp is closed. We once again inform the passengers and FA's as to what is going on. We started to get long tarmac delay warnings from the ACARS. We soon got ramp clearance to taxi into the gate.Arrived at the gate and ran a parking checklist.Gate agents XXX and XXX assisted us with getting everyone off the airplane then I talked with the Fire Captain and the local mechanic.All in all it was an adrenaline packed event and I write this to the best of my recollection. First Officer as well as our inflight team performed expeditiously and with professionalism which made this event much more manageable. I want to recognize them for their efforts as well as our Maintenance Control and Dispatch team.