Don could this also happen because of a heat ridge being further to the north? The way I was picturing it, with a clockwise flow around high pressure, and hot high pressure displaced further north and closer to our latitude, we get more of a southerly component to our wind while areas north of us get the hotter more westerly wind. For us to get that kind of wind the heat ridge would need to be over North Carolina or Virginia in which case we'd be getting the westerly downsloping winds (look at the megaheatwaves in early July 1993, July 1999 and July 2010 and this is what happened.)