Ignition short in wet weather

[jps300E]

My '87 300E will stall when hitting standing water on the road (not necessarily very deep) and after 15 to 20 seconds of cranking, will restart, albeit a bit rough. I don't see where any ignition-related wires are getting wet and it they were, why the ability to restart so quickly? The splash shield is new although some water is present on the top of the left fender well.

Any ideas would be appreciated.