Texas Winter 2024-2025

[wxman22]

The GFS actually looks good up here at least. Just a FYI the NAM’s suite of models (The WRF models which typically perform better than the NAM) are not in agreement with the NAM that could be a red flag that the 12z was a bad run.

[orangeblood]

Hopping in here for a rare post, but while the NAM runs are concerning I wouldn't put all of my stock into it. We've had several events where the NAM deviated significantly from what happened in reality as it started to show the event in range. The model is really best at about 36 hours because for some reason, its solutions tend to diverge more chaotically as it gets farther away in simulation time from its initialization time. In modeling, something like a difference in a microphysics parameterization scheme can cause wildly different results when the overall physics are largely showing the same solution, and for the NAM's case, it is showing the track and speed of the low relatively consistent with the global models and even some of the other mesoscale models like the RGEM. Remember, when dealing with these events it's all about trends. As long as ensembles and other short range models show precipitation, there's reason to build trust that an event is possible, even if the incoming shortwave near Baja california is starting to indicate there will be overall a warmer airmass creeping into the plains which will decrease snow likelihood south of the red river. But, that being said, if the 12z NAM solution appears on the HRRR by tomorrow morning and starts to creep into ensembles more and more as the next 24 hours happens, I'd start to hit the panic button. However, there's no reason to do that yet--and the meteorologists at the local NWS offices around North Texas seem to agree.

Great Post! Thanks for hopping on. When it comes to winter weather, I do agree that we've probably had more misses from the NAM than hits over the years. And those misses have been pretty atrocious

[bubba hotep]

The 12z RGEM is closer to the 06z Euro for the 500mb setup. Both bring the trailing s/w down the Rockies and into the Baja Low. The 12z NAM is about 9-12 hrs slower with that process.

[Brandon8181]

Hopping in here for a rare post, but while the NAM runs are concerning I wouldn't put all of my stock into it. We've had several events where the NAM deviated significantly from what happened in reality as it started to show the event in range. The model is really best at about 36 hours because for some reason, its solutions tend to diverge more chaotically as it gets farther away in simulation time from its initialization time. In modeling, something like a difference in a microphysics parameterization scheme can cause wildly different results when the overall physics are largely showing the same solution, and for the NAM's case, it is showing the track and speed of the low relatively consistent with the global models and even some of the other mesoscale models like the RGEM. Remember, when dealing with these events it's all about trends. As long as ensembles and other short range models show precipitation, there's reason to build trust that an event is possible, even if the incoming shortwave near Baja california is starting to indicate there will be overall a warmer airmass creeping into the plains which will decrease snow likelihood south of the red river. But, that being said, if the 12z NAM solution appears on the HRRR by tomorrow morning and starts to creep into ensembles more and more as the next 24 hours happens, I'd start to hit the panic button. However, there's no reason to do that yet--and the meteorologists at the local NWS offices around North Texas seem to agree.

Great Post! Thanks for hopping on. When it comes to winter weather, I do agree that we've probably had more misses from the NAM than hits over the years. And those misses have been pretty atrocious

I think the NAM is a great tool for sure, but certainly has its limitations as Cerlin mentioned and is much better in the really short term and can be a little junk-ish beyond that.

[snownado]

This was tricky from the start the main players have not moved as forecasted (shocker)

However, the 12z RGEM doubled down!

https://m2o.pivotalweather.com/maps/models/rdps/2025010712/075/sn10_acc-imp.us_sc.png

The RGEM and EURO are pretty much outliers at this point...

Even the early frames of the HRRR are looking more NAM/GFS-ish...

Hi Res WRF is on the Euro side, there are no outliers at this point

Ok, so that's 3, lol

Even then, the vast majority of guidance isn't supporting the EURO and RGEM (and fewer do by each run). And the EURO at least has already caved halfway from what it had been consistently showing.

That said, it would be great if they pull a coup.

[Cpv17]

Hopping in here for a rare post, but while the NAM runs are concerning I wouldn't put all of my stock into it. We've had several events where the NAM deviated significantly from what happened in reality as it started to show the event in range. The model is really best at about 36 hours because for some reason, its solutions tend to diverge more chaotically as it gets farther away in simulation time from its initialization time. In modeling, something like a difference in a microphysics parameterization scheme can cause wildly different results when the overall physics are largely showing the same solution, and for the NAM's case, it is showing the track and speed of the low relatively consistent with the global models and even some of the other mesoscale models like the RGEM. Remember, when dealing with these events it's all about trends. As long as ensembles and other short range models show precipitation, there's reason to build trust that an event is possible, even if the incoming shortwave near Baja california is starting to indicate there will be overall a warmer airmass creeping into the plains which will decrease snow likelihood south of the red river. But, that being said, if the 12z NAM solution appears on the HRRR by tomorrow morning and starts to creep into ensembles more and more as the next 24 hours happens, I'd start to hit the panic button. However, there's no reason to do that yet--and the meteorologists at the local NWS offices around North Texas seem to agree.

Wow, you haven’t been on here in a couple years. Welcome back! I was wondering where you were lol

[txtwister78]

Age old story my friends ... coastal lows always rob moisture from areas further inland in Texas. With the timing of the surface low development off the coast being closer to the timing of the upper level trough/vorticity moving across the state ... there you go. That is assuming it all shakes out like the most recent model runs show. I'm in the camp with orangeblood in that this is a very unusual model change so close to an event. I'm not sure I'm sold on any scenario at the moment.

Just saw your post Porta and laughed that we were both thinking the same thing when the NAM came out but I agree that we need to see more consensus from other models before going all in on the NAM, however the Euro (for what it's worth) looks more and more like the NAM especially out across west Texas where this is quickly becoming a minimal to little impact event out there compared to what models were indicating just 24-36 hours ago.

[BradKingK]

Hopping in here for a rare post, but while the NAM runs are concerning I wouldn't put all of my stock into it. We've had several events where the NAM deviated significantly from what happened in reality as it started to show the event in range. The model is really best at about 36 hours because for some reason, its solutions tend to diverge more chaotically as it gets farther away in simulation time from its initialization time. In modeling, something like a difference in a microphysics parameterization scheme can cause wildly different results when the overall physics are largely showing the same solution, and for the NAM's case, it is showing the track and speed of the low relatively consistent with the global models and even some of the other mesoscale models like the RGEM. Remember, when dealing with these events it's all about trends. As long as ensembles and other short range models show precipitation, there's reason to build trust that an event is possible, even if the incoming shortwave near Baja california is starting to indicate there will be overall a warmer airmass creeping into the plains which will decrease snow likelihood south of the red river. But, that being said, if the 12z NAM solution appears on the HRRR by tomorrow morning and starts to creep into ensembles more and more as the next 24 hours happens, I'd start to hit the panic button. However, there's no reason to do that yet--and the meteorologists at the local NWS offices around North Texas seem to agree.

Great information. Thanks so much for dropping by!

[Ralph's Weather]

When dealing with a Gulf low you have to assume a sharp NW cutoff for precip unless there is a trailing wave to maintain precip.

[SnowintheFalls]

The GFS actually looks good up here at least. Just a FYI the NAM’s suite of models (The WRF models which typically perform better than the NAM) are not in agreement with the NAM that could be a red flag that the 12z was a bad run.

Really hoping we at least see some snowfall here in the Falls!

[South Texas Storms]

Age old story my friends ... coastal lows always rob moisture from areas further inland in Texas. With the timing of the surface low development off the coast being closer to the timing of the upper level trough/vorticity moving across the state ... there you go. That is assuming it all shakes out like the most recent model runs show. I'm in the camp with orangeblood in that this is a very unusual model change so close to an event. I'm not sure I'm sold on any scenario at the moment.

Just saw your post Porta and laughed that we were both thinking the same thing when the NAM came out but I agree that we need to see more consensus from other models before going all in on the NAM, however the Euro (for what it's worth) looks more and more like the NAM especially out across west Texas where this is quickly becoming a minimal to little impact event out there compared to what models were indicating just 24-36 hours ago.

I never bought into the extremely bullish guidance as there was always quite a bit of uncertainty with this system, as there almost always is with TX winter storms. The truth is the most likely scenario is somewhere in between the currently bullish Euro/RGEM and the less bullish ICON/NAM. The NWS official forecast looks good to me still, a few inches of snow is likely across much of north TX later this week.

[Stratton23]

12z GFS really backing off on snow for DFW, 1-2 inches, big totals continue to shift further NE, more rain mixing in on this run, not looking great

[Ralph's Weather]

Radar showing some virga across E TX this morning from a weak little lead impulse that you can see on vort maps.

[Ralph's Weather]

12z GFS really backing off on snow for DFW, 1-2 inches, big totals continue to shift further NE, more rain mixing in on this run, not looking great

We need the phase to happen as early as possible to limit this WAA

[Cerlin]

Hopping in here for a rare post, but while the NAM runs are concerning I wouldn't put all of my stock into it. We've had several events where the NAM deviated significantly from what happened in reality as it started to show the event in range. The model is really best at about 36 hours because for some reason, its solutions tend to diverge more chaotically as it gets farther away in simulation time from its initialization time. In modeling, something like a difference in a microphysics parameterization scheme can cause wildly different results when the overall physics are largely showing the same solution, and for the NAM's case, it is showing the track and speed of the low relatively consistent with the global models and even some of the other mesoscale models like the RGEM. Remember, when dealing with these events it's all about trends. As long as ensembles and other short range models show precipitation, there's reason to build trust that an event is possible, even if the incoming shortwave near Baja california is starting to indicate there will be overall a warmer airmass creeping into the plains which will decrease snow likelihood south of the red river. But, that being said, if the 12z NAM solution appears on the HRRR by tomorrow morning and starts to creep into ensembles more and more as the next 24 hours happens, I'd start to hit the panic button. However, there's no reason to do that yet--and the meteorologists at the local NWS offices around North Texas seem to agree.

Wow, you haven’t been on here in a couple years. Welcome back! I was wondering where you were lol

Been a little busy but I've been keeping up and reading along! But, I do have a degree in Meteorology now!

[txtwister78]

Age old story my friends ... coastal lows always rob moisture from areas further inland in Texas. With the timing of the surface low development off the coast being closer to the timing of the upper level trough/vorticity moving across the state ... there you go. That is assuming it all shakes out like the most recent model runs show. I'm in the camp with orangeblood in that this is a very unusual model change so close to an event. I'm not sure I'm sold on any scenario at the moment.

Just saw your post Porta and laughed that we were both thinking the same thing when the NAM came out but I agree that we need to see more consensus from other models before going all in on the NAM, however the Euro (for what it's worth) looks more and more like the NAM especially out across west Texas where this is quickly becoming a minimal to little impact event out there compared to what models were indicating just 24-36 hours ago.

I never bought into the extremely bullish guidance as there was always quite a bit of uncertainty with this system, as there almost always is with TX winter storms. The truth is the most likely scenario is somewhere in between the currently bullish Euro/RGEM and the less bullish ICON/NAM. The NWS official forecast looks good to me still, a few inches of snow is likely across much of north TX later this week.

You mean not a "2-3 day shutdown". In all seriousness (because it is when you're dealing with impacts to population and infrastructure) but you can tell who really understands the complexities of these events down here in Texas when it comes to forecasting winter weather and who is just looking at one preferred model of choice and running with it all over social media and elsewhere without any regard to the core elements at play. Give credit where credit is due to the folks at NWS because in this era it's tough to block out all the noise and stick to blends, training and more importantly past experience/history.

[rwfromkansas]

Well, this has been a shocking turn of events. I thought since it was 2025 and relative consistency we were set for a fairly good event. I didn't buy 12 inches, and I took out some for melting. But, I was thinking 6-8 was likely, which would be the biggest snow sincewe moved here in 2014. But, likely having school Thursday and Friday now. A few inches of snow won't cancel school even here.

Hugging that Euro. Lol

We will see, glad to see other high-res models don't agree with the NAM.

One question I have is isn't the high pressing from CO? So wouldn't that bring some fresh cold? I would think that would counter the WAA to a degree.

[Yukon Cornelius]

NWS still holding steady up here. However, now that I’ve said that it’ll probably change

image upload

[Gotwood]

NWS still holding steady up here. However, now that I’ve said that it’ll probably change
[url]https://i.ibb.co/nC94V87/IMG-9804.jpg [/url]
image upload

Yeah they have my current high for Thursday at 30 I highly doubt that comes to fruition.

[Cpv17]

Hopping in here for a rare post, but while the NAM runs are concerning I wouldn't put all of my stock into it. We've had several events where the NAM deviated significantly from what happened in reality as it started to show the event in range. The model is really best at about 36 hours because for some reason, its solutions tend to diverge more chaotically as it gets farther away in simulation time from its initialization time. In modeling, something like a difference in a microphysics parameterization scheme can cause wildly different results when the overall physics are largely showing the same solution, and for the NAM's case, it is showing the track and speed of the low relatively consistent with the global models and even some of the other mesoscale models like the RGEM. Remember, when dealing with these events it's all about trends. As long as ensembles and other short range models show precipitation, there's reason to build trust that an event is possible, even if the incoming shortwave near Baja california is starting to indicate there will be overall a warmer airmass creeping into the plains which will decrease snow likelihood south of the red river. But, that being said, if the 12z NAM solution appears on the HRRR by tomorrow morning and starts to creep into ensembles more and more as the next 24 hours happens, I'd start to hit the panic button. However, there's no reason to do that yet--and the meteorologists at the local NWS offices around North Texas seem to agree.

Wow, you haven’t been on here in a couple years. Welcome back! I was wondering where you were lol

Been a little busy but I've been keeping up and reading along! But, I do have a degree in Meteorology now!

That’s amazing! Congratulations to you!