Narrative:

After touchdown during rollout; heavy rain was encountered. ATC gave us clearance to exit the runway at a specified taxiway; I could not discern which taxiway was the correct taxiway; or even exactly where the taxiways were. I had my windshield wipers on high/fast. While slowing and identified where I was supposed to exit; ATC cleared a flight for takeoff. We had not even started our exit off the runway; nor did I know where exactly I was exiting. After the takeoff clearance issued; I tried to alert ATC we were on the runway; [departing aircraft] was simultaneously reading back their clearance. After [departing aircraft] read back their takeoff clearance; I told them to 'cancel their takeoff clearance; [we are] is still on the runway'. ATC; then asked [departing aircraft] to taxi down the runway and make the first available exit.

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Original NASA ASRS Text

Title: B737 Captain reported that after landing; they were still taxiing on the runway when another aircraft was given clearance for takeoff.

Narrative: After touchdown during rollout; heavy rain was encountered. ATC gave us clearance to exit the runway at a specified taxiway; I could not discern which taxiway was the correct taxiway; or even exactly where the taxiways were. I had my windshield wipers on high/fast. While slowing and identified where I was supposed to exit; ATC cleared a flight for takeoff. We had not even started our exit off the runway; nor did I know where exactly I was exiting. After the takeoff clearance issued; I tried to alert ATC we were on the runway; [departing aircraft] was simultaneously reading back their clearance. After [departing aircraft] read back their takeoff clearance; I told them to 'cancel their takeoff clearance; [we are] is still on the runway'. ATC; then asked [departing aircraft] to taxi down the runway and make the first available 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.