Texas Winter 2023-2024

[CaptinCrunch]

This is not one of the headfake SSWs, this is the real deal, and a big one as well.

https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Sounds like Febuary 2021 all over again......

[Texas Snowman]

Interesting…

 https://x.com/nwsfortworth/status/1747742812630896822

[Itryatgolf]

This is not one of the headfake SSWs, this is the real deal, and a big one as well.

https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Sounds like Febuary 2021 all over again......

I highly doubt that, but you never know. That was a once in 50 year event. Very rare but fun to track!! Glad to be in cold side with that system

[Texas Snowman]

This is not one of the headfake SSWs, this is the real deal, and a big one as well.

https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Sounds like Febuary 2021 all over again......

Definitely hope for something more this winter here in Denison since we had only a light dusting of snow with this cold wave. Not sure I want that (or December 1983) again though.

If and when we ever have anything resembling February 2021 again, hopefully ERCOT can handle it.

[Iceresistance]

This is not one of the headfake SSWs, this is the real deal, and a big one as well.

https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Sounds like Febuary 2021 all over again......

I highly doubt that, but you never know. That was a once in 50 year event. Very rare but fun to track!! Glad to be in cold side with that system

I think the SSW that triggered the February 2021 event is similar in time on when it happened.

Does someone have an archive for the 10mb zonal wind back to Winter 2020-2021?

[Ntxw]

Interesting…

 https://x.com/nwsfortworth/status/1747742812630896822

Even more interesting is that the seeds for the higher humidity towards the airport if you were watching satellite obs started at the longer length of Texoma that spans the Washita River. You need at least 100km of warm water to really get a band going and that's likely a good culprit. Lewisville enhanced it downstream. Grapevine is too small to really generate it's own thicker band. Eastern Dallas and Rockwall/Kaufman counties had the lengths of Lavon and Ray Hubbard.

I would actually define this as localized lake-enhanced snow. S/W overhead provided lift at the mid and upper levels but too dry at the lower which is where the lakes come in. Upper flow was west to east, but lower wind was N to S. Essentially it was snowing everywhere above our heads, but only where the humidity was enhanced at the lower levels downwind of the lakes had the chance for it to make to the ground.

Makes you wonder in cold, snow events how much these lakes add to the total in these areas.

[rwfromkansas]

We have had some previous lake effect events that weren't as significant.

What made this one stronger?

The interaction with the shortwave?

There are lots of times that we have cold north winds coming down, and it doesn't generate a snow band.

It seems to require just a perfect setup around here to do so.

[Ntxw]

We have had some previous lake effect events that weren't as significant.

What made this one stronger?

The interaction with the shortwave?

There are lots of times that we have cold north winds coming down, and it doesn't generate a snow band.

It seems to require just a perfect setup around here to do so.

It works the same way in the Great Lakes. Cold winds alone doesn't do it, you need lift from a shortwave coming W->E. We don't get those often here when it's really cold. And it really needs to be really cold, otherwise the ratios aren't enough to make an impact out of like 0.01".

[Iceresistance]

I just found an archive on the 10 mb Zonal Wind, there was indeed a reversal (twice actually) in January 2021, this is indeed similar to what may happen this coming February like it did in 2021.

2020-2021

https://s13.gifyu.com/images/S06yI.png

Now

https://s13.gifyu.com/images/S06rw.png

[Gotwood]

This is not one of the headfake SSWs, this is the real deal, and a big one as well.

https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Sounds like Febuary 2021 all over again......

I doubt anything happens. At least not in our area, Dr Amy Butler said it could bring more cold to eastern US or Europe.

[Stratton23]

Gotwood, I wouldnt write it off, especially with the EPO taking a nose dive in february and a -NAO/ -AO combination, its going to get cold here

[CaptinCrunch]

This is not one of the headfake SSWs, this is the real deal, and a big one as well.

https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Sounds like Febuary 2021 all over again......

I doubt anything happens. At least not in our area, Dr Amy Butler said it could bring more cold to eastern US or Europe.

Until we get into February we're not going to know how much or if this will have any effect for the U.S

Let's just hope the moisture and humidity is available for a good old fashioned doomsday snowmageddon

[Gotwood]

Gotwood, I wouldnt write it off, especially with the EPO taking a nose dive in february and a -NAO/ -AO combination, its going to get cold here

If it means snow here then I’m all in but this weather pattern so far this year has been a crap shoot. Not getting my hopes up.

[Cpv17]

I’m pretty confident the cold will come back in February and precip chances should be better then too.

[Itryatgolf]

Gotwood, I wouldnt write it off, especially with the EPO taking a nose dive in february and a -NAO/ -AO combination, its going to get cold here

If it means snow here then I’m all in but this weather pattern so far this year has been a crap shoot. Not getting my hopes up.

We are under a WWA for mix sleet and fzr. Very light as of now. I'm thinking it gets cold again between the 8th-15th February. Just speculation at this point. Definitely don't want dry cold

[Cpv17]

Gotwood, I wouldnt write it off, especially with the EPO taking a nose dive in february and a -NAO/ -AO combination, its going to get cold here

If it means snow here then I’m all in but this weather pattern so far this year has been a crap shoot. Not getting my hopes up.

We are under a WWA for mix sleet and fzr. Very light as of now. I'm thinking it gets cold again between the 8th-15th February. Just speculation at this point. Definitely don't want dry cold

The 8th-15th Feb timeframe looks interesting to me too. January is typically a dry month. Moisture picks up in February.

[Iceresistance]

That +AO spike may not last long come February


https://s13.gifyu.com/images/S06eZ.png

[Wthrfan]

I just found an archive on the 10 mb Zonal Wind, there was indeed a reversal (twice actually) in January 2021, this is indeed similar to what may happen this coming February like it did in 2021.

2020-2021
https://s13.gifyu.com/images/S06yI.png
https://s13.gifyu.com/images/S06yI.png

Now
https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Explain what this means to me like I'm 5!

[Cpv17]

I just found an archive on the 10 mb Zonal Wind, there was indeed a reversal (twice actually) in January 2021, this is indeed similar to what may happen this coming February like it did in 2021.

2020-2021
https://s13.gifyu.com/images/S06yI.png
https://s13.gifyu.com/images/S06yI.png

Now
https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Explain what this means to me like I'm 5!

During the winter if you want cold, it’s good to have a -AO. It’s one of the main teleconnections that we look for. AO stands for Artic Oscillation.

[HockeyTx82]

I just found an archive on the 10 mb Zonal Wind, there was indeed a reversal (twice actually) in January 2021, this is indeed similar to what may happen this coming February like it did in 2021.

2020-2021
https://s13.gifyu.com/images/S06yI.png
https://s13.gifyu.com/images/S06yI.png

Now
https://s13.gifyu.com/images/S06rw.png
https://s13.gifyu.com/images/S06rw.png

Explain what this means to me like I'm 5!

During the winter if you want cold, it’s good to have a -AO. It’s one of the main teleconnections that we look for. AO stands for Artic Osculation.

That's very interesting. It sounds like you are well-informed about the 10 mb Zonal Wind and its relation to the stratospheric polar vortex (SPV). According to the web search results, the 10 mb Zonal Wind is a measure of the strength and direction of the circumpolar westerly winds in the stratosphere¹². A reversal of the 10 mb Zonal Wind indicates a sudden stratospheric warming (SSW) event, which can have significant impacts on the tropospheric circulation and weather patterns²³. The occurrence and predictability of SSW events are topics of active research in meteorology²⁴.

Some additional information that you might find useful are:

- The ECMWF charts website provides daily distribution and evolution of mean zonal wind at 10 hPa for the Northern and Southern Hemisphere, based on the ECMWF extended range ensemble¹. You can select the desired times and hemisphere using the drop down menu.
- The University of Oklahoma website displays the latest 31-member Global Ensemble Forecast System (GEFS) forecasts for the stratospheric polar vortex, using 10-hPa 60N zonal mean zonal wind². You can also access an ERA5 stratosphere archive at the bottom of the page.
- The Pennsylvania State University website explains the dynamics of the stratosphere and the role of the easterlies and westerlies in the seasonal cycle³.
- The NOAA NCEP-NCAR CDAS-1 website provides monthly intrinsic pressure level u zonal wind data from the Climate Data Assimilation System I; NCEP-NCAR Reanalysis Project⁵. You can explore the data using grids and graphs.

Source: Conversation with Bing, 1/17/2024
(1) Mean zonal wind at 10 hPa - Extended range forecast. https://charts.ecmwf.int/products/exten ... zonal-wind.
(2) GEFS Stratosphere Forecasts - University of Oklahoma. http://arctic.som.ou.edu/tburg/products/realtime/strat/.
(3) Meteo 465 - Pennsylvania State University. https://personal.ems.psu.edu/~brune/m46 ... namics.htm.
(4) Mean zonal wind at 10 hPa - Extended range forecast. https://charts.ecmwf.int/permalinks/mea ... cast-70147.
(5) NOAA NCEP-NCAR CDAS-1 MONTHLY Intrinsic PressureLevel u: zonal wind data. http://iridl.ldeo.columbia.edu/SOURCES/ ... eLevel/.u/.