UPDATE: Over the past month I finally got in contact with a NOAA meteorologist. Well there was a lot of back and forth between me and the NOAA meteorologist that worked with me on this issue over the past month. Long story short is that over the course of a month technicians went out twice to check things out. They came back empty handed each time. I think their focus was on calibration vs. configuration of software that uses the readings and the scope of this issue may be outside of their training. The Meteorologist agreed with me in my findings. But the issue is not critical because the error we are talking about is about .2 to .4 millibars. So nobody is going to do anything more for this.
Here is the final say in the matter and the last communication I received from NOAA and I've come to accept that this is it. But at least I feel good that I was able to track down a responsible person, that understood me, and was able to get this expert to agree with me in my findings. At least now I know that I'm not the only one that knows and who knows maybe someday someone will look at this system and then fix it and then someone will say, "oh yeah, that issue came to light a while ago and we weren't able to fix it."
Final Email from NOAA Meteorologist:
I'd like to provide one final follow-up to your most recent email.
As a meteorologist, I definitely get what you are staying (and have been saying) and personally, I agree with you.
That said, our electronic technicians work based on preventative maintenance tolerance values (i.e. within an acceptable calibration range) as you've surmised. For NWS/FAA purposes, the critical pressure value is the altimeter reading (as that is the pressure variable that pilots utilize), not SLP or Station Pressure. Since the SLP falls within their PM tolerances, they consider the error which you've pointed out, as "noise" (i.e. too small of an offset to make a difference for any NWS/FAA SLP uses). As long as the value falls within tolerance, they unfortunately do not see the need to investigate further - as other maintenance/equipment issues take precedence.
While I would prefer the SLP bias that you've identified to be investigated and corrected, it is unlikely that the technicians will pursue this item further, for the reasons described above. In fact, I even sought the advice of the technical specialist for observing equipment at our Regional HQ following your initial and second emails, and he concurred with our local electronic technicians.
I'm sorry I couldn't assist to resolve the issue that you raised.
Sincerely,
[Name withheld]
I thanked the NOAA Meteorologist for giving me the time of day and working so hard with me understanding and dealing with this issue. I learned a lot in this process. I also got to see some screenshots of the airport weather and METAR software. How nice it was to finally deal with an intelligent individual that took responsibility.