astro won't start in the rain

hey,
My 99 chevy astro won't start when it rains. When i turn the key the engine ticks over but wont fire and start. When i go back to it after a the rain has stopped for a while it will start. Anyone experienced this before, what do you think is the problem? THanks for any help guys

Yup, changed my distributor cap and rotor. Crank it over at night with the doghouse removed, look for a blue lightshow, if there is none, go for the distributor and cap first(cheapest).

Could also be the ignition coil, cracked porcelain on the spark plugs, or the spark plug wires.

Had a similar prob with my 98
Died on the hyway in the rain then started
Had to replace the ignition coil
pretty light show

My 2002 had the exact problem, after rain/wont start. In the end I made my mechanic replace the ignition coil and alternator I had bought online. And now it runs fine. Probably a faulty voltage regulator or worn out brushes inside the alternator that did it. Next time electrical problems arise in a 7+ year old car, start with the alternator as the culprit.