An interesting 24 hours in South Australia and apart from some inaccuracies for the Adelaide region, amazingly well forecast by the BOM at least 2 days prior to the event. As forecast, the Lower Eyre Peninsula and Eastern Eyre peninsula got plenty with falls of over 40mm for Port Lincoln, Tumby Bay, Cummins, Wuddina and Cleve. 30-40mm over Northern Spencer gulf in the Port Augusta, Port Pirie region. I think falls today in other eastern parts of the mid north may be good as well. Again the mid north falls were predicted a few days before by the BOM. Adelaide falls were expected to be light and patchy, again the BOM were right apart from one small blemish. At around 1pm the BOM issued a severe thunderstorm warning including the Adelaide area. On the radio someone from the BOM said that during the afternoon thunderstorms would increase in the Adelaide area with falls of 20-30mm expected! Wow! This was a change from the original forecast. Skies to the N and NW where the weather was coming from looked impressively black and solid. However in the space of less than an hour the heavy cloud band weakened and virtually disappeared, the sun came out and the severe thunderstorm warning appropriately cancelled! Not one drop of rain fell! I did not see the radar pictures to view the impressive collapse. One thing that has always had me curious. Why do rains from northern origin favor the mid north so much and as they move southward always tend to push to the east and miss the Adelaide region. Are there geographical factors in place eg Spencer and St. Vincent gulfs and the Mt. Lofty ranges ? There are of course exceptions but I would say that in at least 90% of occasions this pattern seems to occur.