The RUC MSLP fields and heights aloft look very messy this evening over Canada. There appears to be some unanticipated change in either Canadian METAR altimeter setting or the station elevations for Canadian stations. The fields seem to be well-behaved over the US. The Eta analyses do not appear to have the same problem. Since I believe the Eta uses the SLP reduction rather than alt setting/stn elev in its analysis, I suspect a change in those values may be responsible.

If any NWS folks receiving this know how to reach the SDM on duty at NCEP, please relay this message. I've sent email to some of the EMC folks but imagine they won't see it until Monday.

Has anyone noticed when this behavior started?

thanks

Stan Benjamin