Converged on a 12/21/2024 coastal storm, however ... much higher than normal uncertainty relative to very shortterm. May need nowcast for impacting east/SE regions

[mreaves]

1 hour ago, Go Kart Mozart said:

When I look up DOX, I get Dongarra, Australia?

I don't think any model had it going that far west or east for that matter.

[NorEastermass128]

Looks like I’m just east of the coastal front. West Peabody should be a good spot. 

[George001]

7 minutes ago, TauntonBlizzard2013 said:

There is still a lot of meh guidance out there. I guess everyone is going NAM 100%.
 

lots of high fives for something that hasn’t happened yet 

Nope, the NAM has support. The gfs made a big shift NW at 12z. NAM is good inside 24 hours, so I’m not ignoring it. Am I expecting the 10 inches of snow it gives me? No, but there is a real change at a big positive bust here. 

[Typhoon Tip]

33 minutes ago, brooklynwx99 said:

it's funny, I know you've been mentioning this, but the GFS presentation is what one would "expect" given the synoptics. just odd that we would have had to wait this long for it

 

yeah i here ya.   you know ... sorta supposition but, i've been yammering about this subtle progressive bias in the gfs for years.  it's really almost down to the nuanced level, but it's there .. always tending to pull or stretch at the x-coordinate component of the wave function.  i think it's ultimately related to the same reason that compared to other guidance, by d10 it's typically cumulatively colder heights on the polar side of the westerlies ... even if only by 2 or 3 dm, but i've seen it be as much as 10dm in trough nodes.  that overall integrates just enough annoying more gradient to cause the balanced the g-winds in the westerlies the girder to the ferrel trade latitudes to have necessarily more speed...etc.    

i remember snarking many pages ago ... if there's ever a situation that requires a west correction the gfs would likely be the last model ever admit that.  heh.  i'm not sure it is 'the last' in this case, but seems to have waited until pretty late the game here. interesting

[brooklynwx99]

6 minutes ago, George001 said:

Nope, the NAM has support. The gfs made a big shift NW at 12z. NAM is good inside 24 hours, so I’m not ignoring it. Am I expecting the 10 inches of snow it gives me? No, but there is a real change at a big positive bust here. 

the GFS showing the solution it does is a big deal

[TauntonBlizzard2013]

1 minute ago, brooklynwx99 said:

the GFS showing the solution it does is a big deal

CMC? Looked mediocre. I find it strange it was crickets when that rolled out.

[WinterWolf]

Moderate snow and 30 degrees. 

[George001]

1 minute ago, TauntonBlizzard2013 said:

CMC? Looked mediocre. I find it strange it was crickets when that rolled out.

Even the CMC is more aggressive than the 1-2 I’m being forecasted. It gives me 4-5 inches or so. 

[weathafella]

1 minute ago, TauntonBlizzard2013 said:

CMC? Looked mediocre. I find it strange it was crickets when that rolled out.

It actually had 0.5 qpf for you.  It certainly was improved vs yesterday.  Brett, I know it’s been a tough year for you but sometimes the glass IS half full.  Happy Holidays.

[wxsniss]

And last night I thought NAM should be introduced to DOGE…

This OES already beating my expectations this morning. CF sitting just southeast of city, great snow growth in Brookline.

 

[MuddyWx]

trend is friend

[WinterWolf]

6 minutes ago, wxsniss said:

And last night I thought NAM should be introduced to DOGE…

This OES already beating my expectations this morning. CF sitting just southeast of city, great snow growth in Brookline.

 

Maybe the GFS should instead… 

[CoastalWx]

The NAM I think will be too drunk to verify. 

[dryslot]

22 minutes ago, TauntonBlizzard2013 said:

CMC? Looked mediocre. I find it strange it was crickets when that rolled out.

Why? Its garbage.

[MegaMike]

18 minutes ago, Typhoon Tip said:

I tend to agree ... i outlined a few meteorological aspects a while ago that goes into the why-for the (bold ^ ) tact is advisable. 

altho, i do suggest the NAM physics are very good for these low level hydrostatic gradient deals - just to add.  the gradient/steep elevating frontal slope enhances rising motion along the up-glide that's triggered under what looks like might be under done q-g forcing in that area.  we'll see..    but whether this means more low sfc pressure resulting, farther nw of previous guidance clusters or not, there's classical mechanics of qpf blossoming between central jersey to se nh. 

also noticing a 300 mb exit fan to assist with that over central ne

 

I have a hard time trusting the NAM 3km due to an issue (possibly patched or related to a vendor?) caused by its domain configuration and dynamics/physics options... If I remember correctly, if a large-scale disturbance moved too quickly, a subroutine will sporadically calculate an unrealistic wind speed (only aloft) at certain sigma levels... Can't predict atmospheric flux if a forcing field is kaput. I need to find this case study... It's pretty interesting and it happened twice from ~2016-2020.

The erratic nature of NAM is off-putting too, but I'm thinking that's related to its ic/bcs... Before a system materializes, you're solely relying on ic/bcs from a regional modeling system. Those regional modeling systems cannot effectively predict, or even initialize, small-scale/convective features which leads to significant error over time. The same forecast volatility will likely occur to other mesoscale modeling systems if they ran past 48 hours. 

While on topic: I would like to see vendors start using the RRFS (https://rapidrefresh.noaa.gov/RRFS/; currently under development)... especially for snowfall and precipitation forecasting. It's a unified, high resolution modeling system which runs every hour. Consider it like the GEFS, but with the HRRR. The NBM/HREF are great, but its a waste of resources to post-process different mesoscale modeling systems onto a constant grid.

Let's just be happy nobody mentioned the NOGAPS.

Also not a fan of the ECMWF AI... That model is for data scientists, not meteorologists.

[TauntonBlizzard2013]

34 minutes ago, weathafella said:

It actually had 0.5 qpf for you.  It certainly was improved vs yesterday.  Brett, I know it’s been a tough year for you but sometimes the glass IS half full.  Happy Holidays.

Thanks Jerry. I really do appreciate the kind words. I’ve spent over a decade on this forum now and I appreciate the support and everyone reaching out over the past year, it means a lot.

Ill be happy to get a few inches, would make for a festive weekend anyway.

Happy holidays to all as well.

[MJO812]

22 minutes ago, MuddyWx said:

trend is friend

Horrible down here

[kdxken]

Festive.

[Chrisrotary12]

On 12/18/2024 at 4:43 PM, Chrisrotary12 said:

Can’t wait to be under cloudy gray skies while others get snow. 

Nailed it. 

[Typhoon Tip]

2 hours ago, MegaMike said:

I have a hard time trusting the NAM 3km due to an issue (possibly patched or related to a vendor?) caused by its domain configuration and dynamics/physics options... If I remember correctly, if a large-scale disturbance moved too quickly, a subroutine will sporadically calculate an unrealistic wind speed (only aloft) at certain sigma levels... Can't predict atmospheric flux if a forcing field is kaput. I need to find this case study... It's pretty interesting and it happened twice from ~2016-2020.

The erratic nature of NAM is off-putting too, but I'm thinking that's related to its ic/bcs... Before a system materializes, you're solely relying on ic/bcs from a regional modeling system. Those regional modeling systems cannot effectively predict, or even initialize, small-scale/convective features which leads to significant error over time. The same forecast volatility will likely occur to other mesoscale modeling systems if they ran past 48 hours. 

While on topic: I would like to see vendors start using the RRFS (https://rapidrefresh.noaa.gov/RRFS/; currently under development)... especially for snowfall and precipitation forecasting. It's a unified, high resolution modeling system which runs every hour. Consider it like the GEFS, but with the HRRR. The NBM/HREF are great, but its a waste of resources to post-process different mesoscale modeling systems onto a constant grid.

Let's just be happy nobody mentioned the NOGAPS.

Also not a fan of the ECMWF AI... That model is for data scientists, not meteorologists.

yeah, again .. i don't disagree.  in fact, most nam variations are risky usage outside of convective initialization - hidden secret.   this is a meso-beta scaled consideration below.   

just in this one handling arena, where is near coastal thermal compression/intense hydrostatic gradient ...etc.  when q-g forcing (-omega) runs out over top...   the problem with an overall gradient rich flow regime ( i.e. tending to stretch the x-coordinate ) the globals will tend to outpace the cyclogen response in the lower troposphere.  it's obviously a resolution issue below the boundary pause, where the nam is likely better resolved, it has a lengthier lifted condensation and more proficient latent heat release ...adding to uvm.  better/quicker/deeper uvm response leads to the nam just being faster with cyclogen ... even just marginally so that tends to scrunch the realization closer to the coast when that happens. 

i would also argue it is why the nam has a nw bias at 60-84 hours... it's could be at other times over assessing that instability.

[SJonesWX]

1 hour ago, Chrisrotary12 said:

Nailed it. 

you aren't seeing the tiniest snow flakes ever right now? ground is coated here (barely)

[Layman]

4 hours ago, kdxken said:

Festive.

I envision your own personal stacks are gray and dry from top to bottom, cherry-picking each piece with a moisture meter in hand savoring the best hard wood hearty warmth all season long.  I'm not jealous, you're jealous! 

[kdxken]

10 minutes ago, Layman said:

I envision your own personal stacks are gray and dry from top to bottom, cherry-picking each piece with a moisture meter in hand savoring the best hard wood hearty warmth all season long.  I'm not jealous, you're jealous! 

My personal stack is Black locust. Don't have to worry. It could rain for a year straight and it wouldn't sizzle If you threw it straight in the fire. 

I do cherry pick for my customers which is a pain in the ass. I was doing it today. Did the best I could but if you wait until late December to get your firewood you shouldn't expect perfection. Actually have a lot of people coming tomorrow Hope they bring their shovels.