Applying the Eta-based MOS equations to output from the WRF model has produced less accurate guidance. There will be no WRF-based MOS guidance. Verification results comparing the operational GFS and Eta MOS guidance to Eta-based MOS equations applied to WRF model output are
available at .

To allow users to transition to the GFS-based MOS guidance, the NWS will temporarily run a 32km Eta model at 0000 and 1200 UTC which will serve as input to the Eta MOS. No direct model output from this interim version of the Eta model will be transmitted or made available on NWS servers. More details on this situation are available in NWS TIN 06-40

As always, please contact us with any questions or comments you may have.

Becky Cosgrove
Question Rob, since you seem to know a bit more about the WRF here than I do...

To which forecast hour are they running it? I thought it was going to be to 90 or 108 hrs but I see that grid format will only be available to 84 hrs I think so I am unsure. I could've sworn I heard it was running longer than the NAM.

As the short range model of interest, the NAM runs operationally out to 84 hours. This has always been the case - now that the WRF has replaced the Eta as the NCEP operational mesoscale model it will not change. I would expect MOS guidance from the new system to be available in 6-8 months after all of the bugs get worked out and new regressions can be calculated.
When did the change occur? I still see the NAM running 4 times a day with the WRF only out to 48 hours. Did I miss something? I thought it was the 12z runs today...hmmm. Unless of course the new WRF is still labeled NAM and they just haven't changed it yet.
What might be nice is a "MOS lookalike product" using data from the soundings, so no massaging with equations but simply taking the BUFKIT type data and making it look like MOS for an easier overview...