Texas Winter 2019-2020

[harp]

And this IS a TEXAS winter forum...but alas we love everyone

. I realize that. That's why I sit back and read and try not to step on anyone 'a toes.

[dhweather]

At only 222 hours out, I give it a .001 % chance of happening.

[Texas Snowman]

At only 222 hours out, I give it a .001 % chance of happening.

https://www.tropicaltidbits.com/analysis/models/gfs/2020012712/gfs_mslp_pcpn_frzn_scus_37.png

CAT.

5.

In.

The.

Gulf!!!!!

[sphelps8681]

And this IS a TEXAS winter forum...but alas we love everyone

. I realize that. That's why I sit back and read and try not to step on anyone 'a toes.

I have to say La and Texas are like siblings. We usually are affected by the same weather system.

[harp]

And this IS a TEXAS winter forum...but alas we love everyone

. I realize that. That's why I sit back and read and try not to step on anyone 'a toes.

I have to say La and Texas are like siblings. We usually are affected by the same weather system.

Exactly. What SE Texas gets, we get the next day.

[Brent]

No snow for anyone on the 12z Euro

[gpsnowman]

No snow for anyone on the 12z Euro

Something is brewing though. The future looks good. I am 100% confident a cold front in February will get us down to 32. Now that would be a front!!!!!

[South Texas Storms]

I'm surprised no one is talking about the 18z NAM showing snow in DFW Thursday night. Man this winter is really taking a toll on yall

[Brent]

I'm surprised no one is talking about the 18z NAM showing snow in DFW Thursday night. Man this winter is really taking a toll on yall

It's the nam

[Ntxw]

Been kind of watching the period late week. The GFS has tried to throw moisture into the upper cold column, which can happen. Might want to look back a couple of Saturdays ago when snow fell in North Texas. Need a strong ULL, some moisture, and deep cold air aloft with it. The surface can get colder as the frame nears, got plenty of time for that. Something the globals generally missed and the short range guidance nailed. This ULL may move even a bit further south than the previous, so things might shift some counties southward?

[South Texas Storms]

I'm surprised no one is talking about the 18z NAM showing snow in DFW Thursday night. Man this winter is really taking a toll on yall

It's the nam

Well yeah but aren't yall desperate?

Sure it's a low chance but its non-zero...

[Cerlin]

I missed the NAM just because I’ve only been checking the globals...but that’s enticing.

[TheProfessor]

I definitely think the 18z NAM bears watching. The Skew-T over the heaviest snow has warm air advection moving over a possible source of cold air advection(north-northeast winds cool air advection may be a better word.). Anyways the reason why this is important is because if you get a warm nose to form above but you have heavy melting snow you will absorb latent heat and cool that column. However, if you have a layer of cold below where the snow refreezes it will release latent heat and warm that part of the atmosphere, but if you can introduce some cooler air from the north into that atmosphere it can counteract that warning keeping precipitation frozen. I'd imagine in a setup like this you could see a snow to sleet(or rain depending on depth) transition if a warm nosed formed(if one never forms and the upper level column stays below freezing then you don't have to worry about this at all lol.) but if you can get sufficiently heavy precipitation in that warm nose you'd see it change back to snow.

[Ntxw]

I definitely think the 18z NAM bears watching. The Skew-T over the heaviest snow has warm air advection moving over a possible source of cold air advection(north-northeast winds cool air advection may be a better word.). Anyways the reason why this is important is because if you get a warm nose to form above but you have heavy melting snow you will absorb latent heat and cool that column. However, if you have a layer of cold below where the snow refreezes it will release latent heat and warm that part of the atmosphere, but if you can introduce some cooler air from the north into that atmosphere it can counteract that warning keeping precipitation frozen. I'd imagine in a setup like this you could see a snow to sleet(or rain depending on depth) transition if a warm nosed formed(if one never forms and the upper level column stays below freezing then you don't have to worry about this at all lol.) but if you can get sufficiently heavy precipitation in that warm nose you'd see it change back to snow.

To be honest this is almost always the scenario for the major DFW snow events. Seldom is it blasting cold and then snow. That is why most of the time after it snows, it melts very quickly the rest of the day. DFW's biggest snowfalls in the past 20 years (Feb 2010, March 2015) all happened in similar fashion needle threading. We've seen several systems this winter try to thread that needle and so far only one has produced. A couple of other attempts but didn't quite make it.

A couple of things to watch for

-how deep the models trend such ULL
-850s if they remain below 0C (as well as much of the column)
-Moisture transport
-Trending downward of the surface on NWP

Late Jan/Early Feb is peak snow climo. We need to thread another needle here.

[TropicalTundra]

I currently see a front on the radar but don’t feel much wind outside. Definitely know some rain will come by for my plants!!

[Brent]

0z NAM definitely not as good

Not as much precip overall and no snow in the metro

[Cerlin]

Teasing us...I’ve missed that.

[TheProfessor]

The 500mb trough is further north and more positively tilted than the 18z, definitely not what you want to see.

[aggiecutter]

[Cerlin]

I heard thunder!!! Rain on the way!