I am feeling pretty comfortable with my thoughts from yesterday regarding widespread showers/thunderstorms in the Mid-South for the Sunday-Wednesday period.
Tropical moisture from what may develop into T.S. Erin before making landfall in TX Wednesday/Thursday will interact with a shortwave coming out of the Rockies that will undercut the ridge over the weekend. This energy should also interact with a frontal boundary that will bring fall-like weather to the Northeast (lows in the 30s in Maine!!). I expect the scenario to evolve into something similar to what we had during the last week of June when there was widespread convection with near daily rain chances, primarily in the afternoon/evening hours.
This type of pattern will lead to widespread showers/thunderstorms but as with any convection, not all areas will get a soaking. Back in late June, south-central KY received a widespread 3-5 inches during the week while north-central KY received less than one inch. So someone should get a soaking, but its impossible to say exactly who at this time.
At the same time (middle of next week), what will become Hurricane Dean should be fairly close to making landfall somewhere between Brownsville, TX and FL. The remnants of Dean will move into the southern U.S. shortly thereafter and will provide a good soaking wherever it goes.
From a heat standpoint, I think Thursday will be the last of the 95+ weather through the end of the month. The aforementioned shortwave and cold front this coming weekend should lower heights sufficiently to break down the heat ridge. With the remnants of Dean swirling around somewhere in the midsection of the country during the last week of August, the heat pipeline from the deserts to the mid-south will be shut off for the time being.