Narrative:

We landed normally. Rollout was normal. I considered exiting at [the next taxiway]; but decided not to; as the runway was wet and it would have required heavier braking than would be comfortable for the passengers. I continued to rollout and slow normally. Somewhere around the last 500 ft of the runway; the light rain intensified to an absolute downpour. I believe it just came up abruptly as I don't remember tower giving us any warning of this heavy rain. I continued to brake to exit the runway at the end to the right. During the last 100 ft or so the aircraft began to slide. I maintained full braking and decided to continue straight ahead on the runway surface rather than attempt to turn as I believed the aircraft would possibly slide into the grass. It felt like the sensation of sliding in a car slowly on ice without being able to do anything but hold on! I steered between two blue runway lights at the end of the runway. The aircraft stopped on the runway surface with the nose wheel about 15 ft past the blue lights. I set the brake; advised the flight attendants and passengers that we would need a tug to help us make the turn onto the taxiway. Looking down at the surface I could see there was at least 1.5 inches of water on the runway. We contacted the tower and called dispatch for the chief pilot on duty. The fire department; airfield ops and a ramp supervisor looked us over and told us we did not hit anything with the aircraft or depart the runway surface. We decided the plan was to shut down; have ramp guys push us back on the runway where we could make the planned exit; and taxi to the ramp. I don't remember a discussion about having the tug pull us to the gate. Once clear of the blue lights; we started both engines and taxied to the gate uneventfully.preventative measures: slow down to a crawl when the runway is wet before approaching the end of the runway when conditions are wet! I was shocked that even at a normal and slow taxi speed the aircraft would not slow down further to make a safe exit.

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Original NASA ASRS Text

Title: B737-800 flight crew reported a runway excursion into the overrun area occurred when they lost braking and directional control near the end of the runway in a heavy downpour.

Narrative: We landed normally. Rollout was normal. I considered exiting at [the next taxiway]; but decided not to; as the runway was wet and it would have required heavier braking than would be comfortable for the passengers. I continued to rollout and slow normally. Somewhere around the last 500 ft of the runway; the light rain intensified to an absolute downpour. I believe it just came up abruptly as I don't remember Tower giving us any warning of this heavy rain. I continued to brake to exit the runway at the end to the right. During the last 100 ft or so the aircraft began to slide. I maintained full braking and decided to continue straight ahead on the runway surface rather than attempt to turn as I believed the aircraft would possibly slide into the grass. It felt like the sensation of sliding in a car slowly on ice without being able to do anything but hold on! I steered between two blue runway lights at the end of the runway. The aircraft stopped on the runway surface with the nose wheel about 15 ft past the blue lights. I set the brake; advised the flight attendants and passengers that we would need a tug to help us make the turn onto the taxiway. Looking down at the surface I could see there was at least 1.5 inches of water on the runway. We contacted the Tower and called Dispatch for the Chief Pilot on Duty. The Fire Department; Airfield Ops and a Ramp Supervisor looked us over and told us we did not hit anything with the aircraft or depart the runway surface. We decided the plan was to shut down; have Ramp guys push us back on the runway where we could make the planned exit; and taxi to the ramp. I don't remember a discussion about having the tug pull us to the gate. Once clear of the blue lights; we started both engines and taxied to the gate uneventfully.Preventative Measures: Slow down to a crawl when the runway is wet before approaching the end of the runway when conditions are wet! I was shocked that even at a normal and slow taxi speed the aircraft would not slow down further to make a safe exit.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.