Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 253
Ground Event / Encounter Other / Unknown
General None Reported / Taken
Airport
I am writing to communicate a concern I experienced last night regarding braking performance at MDW. I landed on 31C [in] a fairly heavy [large transport aircraft] in wet good conditions; autobrake max; flaps 40 with a headwind of about 8 knots. I touched down approximately 1200 ft down runway; on speed; smooth; no bounce; auto brakes actuated and reverse thrust was applied; normal maximum braking; decelerated for about three seconds until we hit a 'bump' in runway at 4R intersection.We felt main struts extend (but still on ground) and felt aircraft accelerate for approximately one to two seconds; struts then compressed and normal maximum brake deceleration returned. We exited the runway at taxiway Sierra without incident. My concern is the 31C/4R runway intersection elevation difference has become significant and is affecting braking performance.
Air carrier First Officer reported aircraft deceleration on landing was interrupted when a bump was encountered at the intersection of MDW Runways 31C/4R.