Alright, I don't have access here at work to the site I would normally prefer for this type of question, but I used some other sources and can at least say the following with regard to MDT....
July should end up ~80.0, which, when combined with June's 73.8, should get us close to 77. 2024 immediately stands out as the GOAT with a mean June/July temp above 78 degrees. Then there are a number of other years slightly above that 77 mark. So, no I wouldn't say it's the hottest start ever, but yes I would say it's one of the warmest starts, top 5-10ish. Depending how August goes, it has an outside chance of making a run at the Met Summer record.