Last Sat morning, cranked the starte motor till it finally started, It was rainy and damp. All day started and ran fine. Sunday cranked it over quiite quickly. Monday morning, same thing started instantly. Monday night, car sitting for a while. Raining, when I got in the car, had to crank over the starter motor for a long while, finally stumbled/shuddered to a start, drive 5 minutes, then stalled while stopping, cranked over the starter for a little while, then s huddered to a start, then ran al right that night. Tues morning in damp rainy weather, took forever, then started finally, ran smoothly. Tues night car parked for 8 hrs, attempted to start the car, weather was rainy/downpour, cranked and cranked, but would not start. In dry weather, starts perfectly, in wet damp, rainy weather difficult to start.
Car is 2000 Honda Civic EX, what is the problem,

Sounds like some of the ignition parts are drawing damp. If it has ignition wires and a distributor cap, replace them. If not, maybe look at the ignition module and coils, and coil housing. If you are due for new plugs, change them too. Remove them cold, and put a small dab of Anti-Seize on them.

yeah you have a prob with something getting damp, ^^ like he said, if due time for plugs get them, and wire's if they are cracked. Me personally had a oldsmobile with a four banger, OK in the dry it would boom start right up and run like a champ, wet or damp weather, IE fog or high dew point or rainy it wouldn't start, OK, conections were getting damp. Do check what labman said

My Honda Civic EX 1993 presents the same problem. I will check your helpful comments with the electrician and return with the results soon.

I don't have the same problem, but my '03 civic ex was having a hard time starting and the guy at the dealership told me it could be from switching keys because the chip inside causes it to do that sometimes.

My Honda Civic EX 1993 presents the same problem. I will check...

Changing the battery and the spark plugs eliminated the problem.

Thanks for letting us know what fixed it.