I travelled down the A19 and was in a line of traffic doing about 70mph overtaking slower veicles when the heavens opened. The wipers on high speed were barely coping. I could see brake lights coming on ahead of me. As I slowed down the rain began to pour in. I managed to pull the sunroof partially closed but there was no way I was going to try to drop down the wind deflector and shut it fully in that situation. Even partially closed it was no good as the water was blowing up the windscreen, over the roof and into the car. It was like driving in a waterfall. I've been drier in worse rain in the TA