I have a good friend that is a meteorologist for the NWS. He said anything beyond the 3rd or 4th day is a guess. And sometimes beyond the 2nd depending on conditions.
I tell him it seems like the next 8 hours is a guess on most forecasts.
I wouldn't put much into the specifics. It seems like the trends are mostly accurate. If it shows a cooling trend, there will probably be one at some point around the projection. I wouldn't bet on the exact day or temperature shift until it gets a lot closer.
j