Stebo

Agreed, as it stands I don't expect a massive storm, but something respectable to low end warning in some places especially back in MO.

18z op GFS is drier than popcorn fart, but it doesn't compare to the GEFS which is on a whole much better with more moisture except for one ensemble. Although as someone noted the other day it isn't comparing apples to apples because the physical scheme of the GEFS hasn't been updated like the operational.

They could have summed that whole paragraph up with I don't know, instead of the massive word salad here.

Yeah, this is why I am not sold on anything up or down with this one except to watch the ensembles for trends as they take some of the noise out.

Oh I agree, all the models at this point are completely inconsistent. This is now the 3rd or 4th year in a row where we have had some what consistent models up to day 4-5, then model chaos for 2 days before converging back in the 48-72hr range. There is some issue in all the models collectively and my guess is with systems being in a data hole.

Strong moisture advection, along with strong positive vorticity advection as well. Problem is the Euro is leaving too dry of an atmosphere behind the front on Saturday. I don't buy dew points in the single digits or lower in its wake.

Euro is still way too light on the cold side of the system, also this run is stronger than the 06z run though not as good as the 00z run.

This needs to be cued up with the Super Mario mushroom sound.

DTX Next round of Pacific upper level energy/trough swinging through the Four Corners region on Sunday will spin up another low pressure system coming out of the southern Plains. This low looks to be tracking close to the Ohio River on Monday, presenting an opportunity for accumulating snow to impact southeast Michigan. Magnitude of the surface wave remains in question, as 00z Euro is a bit stronger and farther north compared GFS, but especially vs the flatter Canadian/Icon solutions. None-the-less, GFS ensemble members give the Euro plenty of support, and several members are even farther north and deeper. Euro indicating 3-4 g/kg of specific humidity in the 850-700 MB layer crossing the border which could support several inches with the proper mid level FGEN, even with less than ideal thermal profiles.

EPS is definitely north than 18z/12z runs also stronger, mean of 1002mb at 96hr.

That piece going through Canada is faster and flatter this run so makes sense for the change.

That piece that drops through Manitoba is screwing with things. That wasn't nearly as strong on previous runs.

Too much junk in the northern stream none of it phasing, just getting in the way.

Not really much bias lately.

Yeah it was definitely setting up for a long duration hit with that run, double barrel low with snow associated with WAA with the first low and the CCB with the second low.

I still think the Euro is grossly underdoing the cold sector precip with this one, no matter what the path ends up.

It is north of that, its between Indy and the River.

I disagree with that DTX AFD 100% and furthermore he is basing his forecast on 00z model suite, everything since then has trended north in the EPS and even GEFS to some degree.

All but 5 track a low along the river or north. It is a very substantial shift north/stronger compared to previous runs.

The Euro could very well be right, but in your example it wasn't this close in that it was doing it, we are at day 4-4.5 right now.

Part of the reason why it is weaker is that it is leaving vorticity back in the southwest. No model is doing that and it is a known Euro bias. With a weaker ejection and trailing the vorticity in the southwest, the vort max is easier to shear out instead of coming out as a shortwave.

GRR The Monday system... The GFS has been forecasting this for nearly a week now and the ECMWF has since the 10th /00z run been bringing the storm closer to us on the operational runs. The 12/00z run brings snow to GRR from the ECMWF. Since this is polar closed upper low dropping south into and southern stream system, this could be power house storm. We will have to watch this closely. DTX Yet another system will then track near the southern Great Lakes from the four corners Monday and Monday night. GFS and ECMWF remain far apart with their solutions but the main story will be that a strong low may track through the Ohio Valley region which would put southern MI in the colder, deformation region of the low. Depending on how far north or south it tracks will determine how far north precipitation can reach and what ptype will occur. The piece of the jet that will be responsible for this storm isn`t set to reach the NW conus til Saturday night so may be some time before models really start converging on a track.

Yeah it's a step. Compared to other models it is on the weakest/furthest south envelope.

I mean it isnt even Christmas yet and you are Southern Indiana. Evansville only averages 12.1" and Cincinnati is around 16" I believe. Climo is pretty against you getting snow of significance in general let alone this year.

Euro out to 99 hours it should come north some this run the low over the Labrador is weaker this run leading to less confluence in the east along with a weaker high coming down its backside.