The METAR.rwx file you provided doesn't look like a standard one. Are you using some third-party weather addon? I couldn't find an indication of one in your log, but that METAR came from someplace. If you're using NOAA, perhaps it's not the latest version or it's not installed properly.
However, I was able to load that METAR.rwx in SMP/RWC just fine, so the problem's not the METAR file itself (assuming you're using SMP 4.0.1).
As far as I know, you're the only person experiencing this sort of thing. Re-installing X-Plane from a clean installation might be a good idea, to rule out some unique quirk of how your many add-ons are installed.