Dont know why. I travelled from Korat to Bkk earlier - back less than an hour - and the roads were heaving.
Saw several accidents. The first notable one was a small lorry, en route to Korat, I assume, that was parked about 15 metres into some shrubs / bushes and facing the direction it came. Didn't seem particularly bashed up. The 2nd, Bkk bound was again in the bushes, but this time parked quite high seemingly on top of some bushes and again, facing the way it came. Pretty bashed up at the front. The 3rd was more of a pain and a few cars weren involved, but only one was still on the road, blocking a lane and a bit en route to Bkk, causing even more congestion. It had clearly spun, and was at 45%, sort of facing the way it had come and the front was visible and pretty smashed up, the rear was still attached to the barrier. The driver I assume, was looking forlornly at the mess and on the phone, the other cars were parked up on the side of the road.
Apart from those, the other incidents were shunts, with what seemed the car behing going into the back of the car in front. Generally minor damage.
At times there was absolutely totential rain accompanied by lightening and visibilty was terrible. Most cars slowed right down, there was little choice, but the idiots were still about driving too fast and too close when they couldn't pass the vehicle in front.