1/23/26-1/25/26 Winter Storm Thread

[Daniel Boone]

2 hours ago, Holston_River_Rambler said:

How does the NBM still show this? (Note this is not a response to what tnweathernut posted)

It supposedly uses all the Ensembles. That's from the NWS. Looks to me as if it's still Yesterday's being used.

[tnweathernut]

The 12zNAM is a crippling ice storm for a bunch of people - even well into KY.............. but as was said, it's the NAM at range.  I'd still like it to have shown a period of snow first, but here we are.  lol 

[Carvers Gap]

This is Wall's X post, but cleaner and easier to read.  This is the most recent WPC discussion about interaction between the northern and southern branches, the NBM being "off", and potential adjustments north(with the snow line) in their forecasts.

Model guidance generally remains in good agreement with the aforementioned large scale pattern evolution, however differences in the details persist. The most notable question deals with how much interaction we see between the southern stream and northern stream energy over the Plains, and the overall depth/strength of the resultant trough. More interaction and a stronger trough would likely result in stronger downstream ridging and thus a farther north storm track. This is indeed what just about all the 00z models are trending towards. Generally a clean sweep, with the deterministic physics based models, ensemble means, and AI guidance all shifting north with the storm track. This trend really has little to no impact on the fact that a widespread and significant winter storm is going to occur...but it does play a big factor in exactly where the rain/ice/snow lines set up. So how confident are we in this trend, and will it continue or revert back to earlier runs, is the big question. Given the nearly unanimous trend in this direction, and at least a couple model runs in a row showing such a trend, it does seem like this shift has some merit. However, overall run to run consistency has shown pretty large swings with the exact handling of both the southern and northern stream energy. Suspect that the exact details of these features is far from settled upon...especially the northern stream energy which is currently strung out across much of western Canada into the arctic. Thus tend to think that the unanimous model trend could be a slight mirage and suggests more confidence in a solution than there actually is at this point. Either way, it should be stressed that in just about every outcome we get a widespread and major winter storm with many areas getting significant impacts regardless of these exact details. These details are, however, important for exactly where the maximum snow and ice totals occur. The current WPC QPF and temperatures were derived before much of this 00z guidance was available, and thus is a bit south of the new consensus. As described above, no guarantee we dont see a shift back south in later models...but assuming some persistence in the 06z/12z models then the WPC update today would likely shift north to at least some extent. Behind this system the general troughing in the east and ridging in the west will persist. There is quite a bit of run to run variability with the shortwave details which does result in quite a large spread in the max/min temperature forecast across the Plains. The NBM was in line with the model means, so we did not make any changes. However, it should be noted that we will likely have some larger than normal errors...just hard to stay whether colder or warmer wins out along this ridge/trough interface.

 

 

[Daniel Boone]

1 hour ago, Carvers Gap said:

I think with that Euro setup as is...it is going to try to split those two highs and head for the Lakes.  What I can't know for sure is if the Euro is trending back stronger w/ the hp to the Northwest.  The differences, even after that slide, grow pretty massively.  The GFS is just weaker (but trending stronger) w/ the STJ pulse.  I would really, really like to know which models got the bulk of the hurricane date overnight, and if one model didn't get it.  To me the hp differences in the Plains look like a data error or absence of it...I just don't know which model is handling that hp over the Plains correctly.  That feature is drastically affecting the overall synoptics of the storm.

That's a Scenario that looked plausable to me after seeing the UK last night but didn't want to Debbie down anymore. A strong ejecting system with a northern vort pull and a weakness between hp Area's can allow for a conduit to open as we know. Webb began fearung that yesterday Afternoon. I think Bamwx was just going by Climo and maybe desire in his earlier North trend depiction. 

      Hopefully that Northern Plains HP strengthens and that Northern vort doesn't pull the Baja LP. That's really our hope. 

[Daniel Boone]

6 minutes ago, tnweathernut said:

The 12zNAM is a crippling ice storm for a bunch of people - even well into KY.............. but as was said, it's the NAM at range.  I'd still like it to have shown a period of snow first, but here we are.  lol 

Not surprised. It's all went from exhilarating to sickening. 

[fountainguy97]

if this does just go miller A I bet there will be some NW flow to soothe the wounds haha

[Carvers Gap]

10 minutes ago, Daniel Boone said:

That's a Scenario that looked plausable to me after seeing the UK last night but didn't want to Debbie down anymore. A strong ejecting system with a northern vort pull and a weakness between hp Area's can allow for a conduit to open as we know. Webb began fearung that yesterday Afternoon. I think Bamwx was just going by Climo and maybe desire in his earlier North trend depiction. 

      Hopefully that Northern Plains HP strengthens and that Northern vort doesn't pull the Baja LP. That's really our hope. 

Yeah, this winter Bam has flip-flopped more than a mackerel that just got pulled into the boat.  But a broken clock is right twice a day....I think he went warm for the second half of January, and then walked it back the next day.  I don't understand the fascination w/ their stuff.  There are so many other great mets and met resources which don't push clicks.  That is all from me on that subject.

The GEM-para nailed this trend.  It has been good this winter.  The WPC post above is really well written.  It explains some of the issues they are dealing with, and some of that we actually discussed here - I hadn't read that until about ten mins ago.   Just been doing this hobby long enough to know the pitfalls w/ stuff like this.  I think ultimately the mishandling of the Baja low was yet again a problem.

What I will be interested in...does a cutter now set the table for the next system?  If that verifies, it will change the next 5-7 days worth of tracks for vortices traversing the country.

[Hillbilly]

So, just to confirm the trending model consensus; the last two runs of the European and other models are telling me that confidence is growing that there is nothing to be concerned about because any frozen precipitation that falls will get melted away quickly on Sunday?

[Daniel Boone]

1 minute ago, Carvers Gap said:

Yeah, this winter Bam has flip-flopped more than a mackerel that just got pulled into the boat.  But a book clock is right twice a day....I think he went warm for the second half of January, and then walked it back the next day.  All winter long.  I don't understand the fascination w/ their stuff.  There are so many other great mets resources than sites which just push clicks.  That is all from me on that subject.

The GEM-para nailed this trend.  It has been good this winter.  The WPC post above is really well written.  It explains some of the issues they are dealing with, and we actually discussed here - I hadn't read that until about ten mins ago.   Just been doing this hobby long enough to know the pitfalls w/ stuff like this.  I think ultimately the mishandling of the Baja low was yet again a problem.

What I will be interested in...does a cutter now set the table for the next system?  If that verifies, it will change the next 5-7 days worth of tracks for vortices traversing the country.

Yeah, it will change the whole Picture for at least that period. May cause the Trough to want to setup a bit further West over the Plains . May not hurt to start watching the MJO more now. 

[Carvers Gap]

12z RGEM at range.  It will often give us clues for the upcoming GEM run.

For posterity and the eventual forensics investigation into this...If I hadn't seen 0z last night, I would say is that is going to be a severe ice storm if that low kicks out late or a snowstorm if it goes with that 1050 high.  Usually, 1050 highs are money for frozen in this forum.  However, there is definite precedent for it to rain behind big highs like that, but still is crazy to watch.

[Carvers Gap]

Take a look at the 12z NAM vs GEM after 72.  NAM is amped.  RGEM is much flatter.  Again, short range models at range...buyer be warned.

[Wurbus]

Rufus looked like it ticked slightly south at the end of the run. Still a mixed bag of precip for most of TN though.

[tnweathernut]

There's a touch less interaction and it's colder at 78 than the prior run at 84, but it's really splitting hairs from the looks of the 12z RGEM at 500.

[Scottie16]

ICON🫣


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[fountainguy97]

Not seeing anything of note on 12z so far. Not looking good.

[tnweathernut]

Maybe it introduces the possibility of two distinct waves though?

[Carvers Gap]

The 12z ICON has ice into southern MS.

[Carvers Gap]

The 12z ICON has a low in the Panhandle at 96 w/ a faint reflection west of the Apps.  Looks icy...very icy for most of the forum area.  It does try to form a Miller A, and that must be watched w/ a slp in the Panhandle, but it just isn't organized enough.  Not a textbook cut, but some energy transfer is evident.  Main low stays along the Panhandle into souther Georgia.  The reflection into the Tennessee Valley causes thermals to get wrecked...and it produces ice.

[Carvers Gap]

7 minutes ago, tnweathernut said:

Maybe it introduces the possibility of two distinct waves though?

It wouldn't be the first time w/ an overrunning event - a true over-running event.  I think you noted that often precip will get out front w overrunning, there is a pause, and the rest comes out.  WPC said it best when it alluded to the illusion of consensus....  Looks to me like a thump of snow, sleet transitions, ice(a lot of it), and then rain.

[Carvers Gap]

The 12z ICON was significantly weaker (compared to 0z) and w/ less precip.

[Tucker1027]

Honestly have no idea what to prepare for… Ice or a muddy back yard…


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[tnweathernut]

1 minute ago, Carvers Gap said:

It wouldn't be the first time w/ an overrunning event - a true over-running event.  I think you noted that often precip will get out front w overrunning, there is a pause, and the rest comes out.  WPC said it best when it alluded to the illusion of consensus....  Looks to me like a thump of snow, sleet transitions, ice(a lot of it), and then rain.

I think for many, a thump of snow would be something that would help get past the sting of whiffing in that department.  Some modeling is very brief with snow before a changeover and just looking at how the setup has moved, that wouldn't surprise me either.

[Carvers Gap]

The 12z GFS is rolling....

[Wurbus]

Is it just me, or does the AIGFS not look too bad for us. Slight warm nose, but nothing like Euro.

[Tucker1027]

GFS is more stubborn than my wife…. Must be why I like it.


(Sorry for the banter)


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[GBOVolz]

Is it just me, or does the AIGFS not look too bad for us. Slight warm nose, but nothing like Euro.

Carver going silent for 15 minutes bothers me more than the Euro.


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[tnweathernut]

It's not interacting with the energy in the southwest in the same way at 84 at 500mb.  That allow the height field to be suppressed a bit more in the east with the initial slug of moisture.

[Weatheriscool]

The GFS is a convoluted mess; does that stuff at hour 84 back in Texas still have to come through? 

[Carvers Gap]

1 minute ago, GBOVolz said:

Carver going silent for 15 minutes bothers me more than the Euro.


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12z GFS is snow for the northern 2/3 of the forum for the first wave.  @tnweathernut, that sure looks like it is going to string out into two waves...or more.

[Tucker1027]

Is the GFS the two wave solution some were talking about?


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