A C421 pilot began an approach to a Class B airport only to execute a missed approach because of weather on final. ATC suggested a nearby airport with a GPS approach which the rushed reporter attempted but in IMC descend too low approaching towers and finally landed at a third airport with better weather.

Narrative

I had been cleared for the ILS. A line of thunderstorms was approaching the airport but according to my Nexrad and onboard weather radar; I would land well before the line reached the airport. I miscalculated. The Tower reported windshear on final. The 757 ahead of me declared a missed approach. All the airliners on the ground began requesting shutdown to the Tower. Within a few seconds; I hit some rain and turbulence. Nothing severe; but given what all the airliners were doing; I called the Tower and told them I wanted to execute a missed approach. They gave me a heading of 090 and 3;000 and suggested the GPS to a nearby airport. I accepted and began to locate the chart. TRACON cleared me for the approach 2 miles from the FAF. I loaded the approach in the GPS and engaged the autopilot. Then I flew into VMC and saw the airport. I began to descend visually. TRACON called and gave me a low altitude alert. I told them I was visual and they handed me off to Tower. As I keyed the mike to call Tower; I flew into IMC - rain and turbulence. The line of weather enveloped my airplane. I told the Tower that while I was VMC; I was now IMC and needed to execute a missed approach. Tower told me to turn to 090 and climb immediately to 3;000 and said 'you've got antennas at 12 o'clock'. I made the turn and climbed immediately. Tower vectored me further east about 25 NM to land uneventfully at a third airport. I never should have accepted the approach to the second airport. I did not have time to prepare. I barely got it loaded into the GPS and I did not have time to study the approach plate. Because I was in VMC; I decide to proceed visually. This was a mistake as weather conditions were changing rapidly and soon enveloped me in IMC. By this time; I was below the proper altitude for the approach and in conflict with terrain (antennas). I should have asked for a vector to a more distant airport (like the third airport) which would have given me time to prepare and shoot a proper approach. I think the intensity of the situation (nearby thunderstorms) and the speed at which the weather was changing affected my judgment. I blindly accepted what the first airport suggested and tried to make it work. Additionally; knowing thunderstorms were approaching my destination; I should have thought through my alternate plan of action beforehand and not waited for ATC to suggest something.