One thing with the rainfall will be the timing. If it is too early it will keep those temps held down... probably in the 70s. If it takes a little while to get here then we could see highs reach the low or mid 80s. So it's all about the timing. The cloud cover has already arrived and that will also work against the temps on Wednesday afternoon. Those clouds can really knock those daytime highs down and never even produce the first raindrop. Even in the summer months! In Wednesday's case... temps could vary by 5-10 degrees. This can make or break a good forecast. Then you factor in the rain and you have a whole new series of problems.
This drink of water comes at a pretty good time... we are 1.34" behind on rainfall for July. We are obviously running out of time since the post date on this is the 21st. There are a few chances of rain coming up over the next few days. We'll see widespread rainfall on Wednesday and scattered stuff on Thursday. We coud pick up around an inch or less by the time it is all said and done. Which won't solve the problem, but it will close the gap between. With the clouds and rain around it looks like highs will remain in the 80s.
The real chance for summer heat looks like it could occur on Saturday. Highs have a chance of making it into the upper 80s. My mind could begin changing Wednesday when I see couple of model runs. As of right now I am keeping the heat in the forecast.