Ford Repair: Bucking Truck, exhaust gas recirculation, spark plug wire

Question
What could cause my F150 V6 4WD to buck during high humidity or raining, and no warning lights came on?  While driving on the highway.  I have had no repairs on the truck since I bought it.  

Answer
Hello and thanks for the question...I'll try to help.
 What I would suggest is you check a few things.......
One is the tune up condition of the vehicle, and the second is the EGR (Exhaust Gas Recirculation) system. It seems that the what you have told me is similar to a distributor cap being cracked, or a spark plug wire "leaking". In your vehicle there is no ditributor cap. It does however, have a short spark plug wire, one at each cylinder ignition coil.
I would start there.
Hope this helps,
Erik