BigFKahuna

I have an issue with my 2004 530i that I purchased last year. I love the car, but when I lock the vehicle using the key fob, thereby setting the factory alarm, it goes off unexpectedly in hot conditions. This happens nearly always when it is above 20 Celsius in direct sun, or on warmer days (above 30 Celsius or so) even when not in direct sunlight. This issue never happens in the winter. I live a couple of hours away from the closest dealer so it is difficult to get the car in to check this out. Does any one have any suggestions that I could bring to my local technician? I do believe the local guy has access to full BMW diagnostic software.
TIA!