2002 blazer wene it israining wont startor hard to start it tunes over well not start
Are you getting a CEL when it is running?
I suspect a problem with the engine not getting spark in high humidity conditions. Could be spark plugs, spark plug wires, and/or coil(s).
How many miles on your vehicle?
When were the spark plugs last changed?
Usually s[ark plug wires and/or distributor cap ate the first things affected by rain.