I’ve been watching those maps since yesterday morning and they haven’t adjusted a whole lot with the models flip flopping. Highest totals have been brought down to earth but the coverage of 4-6” totals has increased south.
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Wintry Machine Learning Mauler 1/30-2/1
- Thread starter SD
- Start date
I’ve been watching those maps since yesterday morning and they haven’t adjusted a whole lot with the models flip flopping. Highest totals have been brought down to earth but the coverage of 4-6” totals has increased south.
iGRXY
Member
Geez there's 1" hr embedded rates in the 3K.
They do mention it, just not something you can put on a map very well.
,
The 3km is my favorite CAM...HRRR is a distanced last for me. But....I can't discount it as an option...it's essentially what Brad P just put out for his call.
The 3km is my favorite CAM...HRRR is a distanced last for me. But....I can't discount it as an option...it's essentially what Brad P just put out for his call.
Convective banding showing up. Someone is going to get obliterated under one of these bands. Thundersnow is possible, based on some of the soundings. Upstate into the western NC Piedmont and out east under the influence of the coastal. Cool to see.
Cary_Snow95
Member
Given the massive differences it continues to make me curious why the 3k NAM is 4-5 degrees warmer than the 12k
Ninergreen
Member
Issued at 3:16pm
Lowered totals by around half for W-S. Will be interesting to see what happens after those most recent runs with that ULL snow band getting up into the Triad/Forsyth County . Whomever gets under that band is going to have fun.
The 18z NAM has RDU in the 17-19 degree range for the heaviest snow. The Carolina Crusher was near freezing, I believe (indeed, it started as rain). This would be even better. 
EDIT: And the 3km NAM is ~5 degrees warmer, which seems like a bias it has based on how warm it was for last weekend's storm at the surface.
EDIT: And the 3km NAM is ~5 degrees warmer, which seems like a bias it has based on how warm it was for last weekend's storm at the surface.
You can see on the 3km NAM the the dry slot was there, but still ended up with more than the HRRR. As many have said, this is going to be a nowcasting event and I totally expect surprises. I still like 3-6 for us.
Webberweather53
Meteorologist
Yeah I think the CAMs are having some convective feedback issues with the coastal low offshore. Some of that is probably real to a degree but a lot of it arguably isn’t. Likely a big reason why the 3km and 12km NAM look so different east of Charlotte and GSO
Is that a situation where the higher resolution becomes too much of a good thing? And so it hurts the model?
Mpirone12
Member
Could it be they are picking up the 500 mb layer instead of 700 mb?
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Crow
Member
So do you buy the 12km more than the 3km?
BHS1975
Member
Like how the 3k likes to amp up hurricanes.
It was running warm for last weekends storm as well
NCWeatherNow
Member
Mping report in the Triad 
WEATHERBOYROY
Member
I expect there to be a lot more precip that is not being modelled, with the base of the trough, especially with a closed core, as it pivots east. If that occurs there should be really good rates in the frigid air.
I agree. For this robust a synoptic system with a closed low and favorable lifting, I just don't buy the CAMS having such weak FGEN and WAA. Models always seem to struggle with underestimating the forcing mechanisms, and I don't see this storm being any different.
Precipitation almost always verifies further north and west, especially given such a well-defined low. I think QPF will verify on the higher side once it's said and done.
Looks like we are going to get another iconic run out of the ICON. 18z looking solid so far, it's starting to wrap up here..
18z rgem coming in and identical to 12z.
Pants buster
Triplephase93
Member
Flurries flying in the Murfreesboro Tn area.
Rgem really honing in on the grand strand up to Wilmington getting raked as the low bombs offshore
packfan98
Moderator
Locked in.
NWG_WX14
Member
RGEM seems locked in
Speaking of which. Is there gonna be an obs thread?
JQPublic
Member
The HRRR is within Range Right?
Webberweather53
Meteorologist
Yeah that’s a good way to think about it.
Sometimes when we’re trying to explicitly resolve convection with the high res CAMs, it can cause more harm than good. The wild swings you’re seeing run to run are part and parcel with that. Things like downstream mass subsidence and divergence/convergence, moisture blocking, how that convection changes the flow pattern ahead of the trough (pumps the ridge) etc. can get all out of whack and cause massive changes between runs over us.
In this setup, we are basically testing the limit of what kind of convective environment we can get at this time of the year over the Gulf Stream and it’s much easier for model biases to show when you push things to the limit like this.
The 18z ICON looks quite similar to the RGEM, too (not that it really matters at this point).
packfan98
Moderator
if you ask me the rgem has a better chance of verifying than the apocalyptic dry runs for the triangle
packfan98
Moderator
nizzle has a similar look…
BrickTamland
Member
I agree. I think 6 to 8 here is good. HRRR really is the main one with the dry runs.
I decided to check RDU's plumes from the 15z SREF and...um...that would be 13.09" for the mean. 
fun thing to think about: the cells out in the ocean will be supercells. hodographs say they should be stationary if they are right movers, yet modeling has them racing away NE
packfan98
Moderator
So does the MPAS. I have no idea what this model is, but it has to help give more support to the similar looking models. I have to think the hrrr and NAM’s are struggling a bit. Maybe they will come around at 0z. Still interested on the euro suite this evening to see which camp they are in.
Catfish
Member
I particularly like the part about heavy bands that you typically only see in the Great Lakes region.
Btownheel
Member
Have to say, feeling pretty good with Rufus and RGEM in lockstep like that.
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Stormsfury
Member
Well, the ICON is actually the furthest north with the upper low and goes negative tilt a bit later.
