Texas Winter 2017-2018

[orangeblood]

Question for a knowledgeable one. In order to get a true McFarland Sig over Texas, do we need a stout southeast ridge?

Typically, for the big winter storms (especially sleet/ice storms) we usually need some resistance from a southeast ridge in order to dig enough S/W energy to the west/southwest of us - it creates a battleground right over the southern plains or overrunning setup

[gpsnowman]

Thanks for the response orangblood. This is getting very mouth watering.

[Brent]

Question for a knowledgeable one. In order to get a true McFarland Sig over Texas, do we need a stout southeast ridge?

Typically, for the big winter storms (especially sleet/ice storms) we usually need some resistance from a southeast ridge in order to dig enough S/W energy to the west/southwest of us - it creates a battleground right over the southern plains or overrunning setup

Yes I remember a couple storms here before I left Alabama where yall had the fun and Alabama had record heat/severe weather(Christmas 2012 and the 2013 Ice Storm comes to mind)

[wxman57]

I was just talking with my cold-mongering coworker in the cubicle next to me. We've been working together since the late 1980s, by the way. I was telling him that the 500 mb pattern in recent GFS runs reminds me of the Thanksgiving week Texas ice storm of 1993. I still have those model forecasts printed out in my file cabinet. Back in 1993, the GFS was predicting that Arctic air would plunge down the plains. However, it developed an upper-level low over Nevada/Utah as the front reached central Texas. The main model (may have been the AVN or MRF back then) didn't handle shallow Arctic air very well at all (sound familiar?).

What the model did was to move the Arctic air northward as a warm front as the upper-low dipped southeastward toward New Mexico. The model had the front moving northward across northern Oklahoma a couple days out. Wrong! Arctic air doesn't do that. The front was out in the NW Gulf of Mexico, not northern Oklahoma. As a result, freezing rain and sleet covered much of Texas, and Leon Lett went down in Dallas Cowboys history for his bad play in the Thanksgiving game.

The moral of this story is that whatever the American model has been named over the past 25 years, it still doesn't handle Arctic air very well. To me, this is looking like more of a freezing rain and sleet event rather than a snow event for Texas. However, it's still 12-14 days out, so I don't feel too confident about anything until the Arctic air is actually present in southern Canada and on the move south. that won' happen for another 10 days.

[ThunderSleetDreams]

11 straight runs and 12 out of last 14. I’m not sure I’ve ever seen this consistency this far out.

[Tireman4]

11 straight runs and 12 out of last 14. I’m not sure I’ve ever seen this consistency this far out.

Just like the Cowboys of the 1970's and early 80's..consistency my friend.

[Ntxw]

Question for a knowledgeable one. In order to get a true McFarland Sig over Texas, do we need a stout southeast ridge?

Typically, for the big winter storms (especially sleet/ice storms) we usually need some resistance from a southeast ridge in order to dig enough S/W energy to the west/southwest of us - it creates a battleground right over the southern plains or overrunning setup

Orangeblood has covered it here, but as said the SE ridge is a block. It prevents storms and cold from sliding east of here. It has no path to go but due south to Brownsville.

In general it is one of the necessities. His paper states zonal -PNA bowl shaped trough is necessary. -PNA induces the SE ridge

The two most recent McFarland 500mb configuration is December 2013 and February 2011

[orangeblood]

Question for a knowledgeable one. In order to get a true McFarland Sig over Texas, do we need a stout southeast ridge?

Typically, for the big winter storms (especially sleet/ice storms) we usually need some resistance from a southeast ridge in order to dig enough S/W energy to the west/southwest of us - it creates a battleground right over the southern plains or overrunning setup

Orangeblood has covered it here, but as said the SE ridge is a block. It prevents storms and cold from sliding east of here. It has no path to go but due south to Brownsville.

In general it is one of the necessities. His paper states zonal -PNA bowl shaped trough is necessary. -PNA induces the SE ridge

The two most recent McFarland 500mb configuration is December 2013 and February 2011

Yep, Dec 2013's upper air pattern is the 1st thing that comes to mind when looking at these forecasts. Check these similarities out:




Now, what is even more interesting about this setup is that that Alaskan ridge is much stronger and the trough much deeper....this has the potential to be much further south/more widespread than the Dec. 2013 ice storm

[Ralph's Weather]

Yep, Dec 2013's upper air pattern is the 1st thing to comes to mind when looking at these forecasts. Check these similarities out:

Now, what is even more interesting about this setup is that that Alaskan ridge is much stronger and the trough much deeper....this has the potential to be much further south/more widespread than the Dec. 2013 ice storm

I noticed the modeled 585 ridge in the GoA, 2013 was in the 560s and 1983 was 570s from what I can tell.

[orangeblood]

European still having issues resolving Eastern Pacific in day 9-10. GFS and Canadian much more consistent...

[Portastorm]

The GFS and Euro ensembles are a lot closer than the operational runs of each.

[Ntxw]

Yep, Dec 2013's upper air pattern is the 1st thing to comes to mind when looking at these forecasts. Check these similarities out:

Now, what is even more interesting about this setup is that that Alaskan ridge is much stronger and the trough much deeper....this has the potential to be much further south/more widespread than the Dec. 2013 ice storm

I noticed the modeled 585 ridge in the GoA, 2013 was in the 560s and 1983 was 570s from what I can tell.

1983 bombed upper 580s well into Alaska. It was one of the most extreme Alaskan blocks in the last century

[Ralph's Weather]

Yep, Dec 2013's upper air pattern is the 1st thing to comes to mind when looking at these forecasts. Check these similarities out:

Now, what is even more interesting about this setup is that that Alaskan ridge is much stronger and the trough much deeper....this has the potential to be much further south/more widespread than the Dec. 2013 ice storm

I noticed the modeled 585 ridge in the GoA, 2013 was in the 560s and 1983 was 570s from what I can tell.

1983 bombed upper 580s well into Alaska. It was one of the most extreme Alaskan blocks in the last century

Thanks for that info, I lost my link to the historical map site I liked in the past and guess I did not save the maps to my work computer.

The long term SW fetch with sagging Arctic air makes for a concerning ice storm potential.

[TeamPlayersBlue]

Still so so so far out. You guys have taught me to pay attention to the pattern this far out, but not the specifics at the surface.
With that said, it looks like the chances of -EPO is happening. When it shows the ridge happening 5-7 days out, I'll start getting real excited.
The massive ridge and its location could be big for us but still too far out. Someone posted the 30 mb chart, this looks to be helping this ridge become a monster.

[ThunderSleetDreams]

Still so so so far out. You guys have taught me to pay attention to the pattern this far out, but not the specifics at the surface.
With that said, it looks like the chances of -EPO is happening. When it shows the ridge happening 5-7 days out, I'll start getting real excited.
The massive ridge and its location could be big for us but still too far out. Someone posted the 30 mb chart, this looks to be helping this ridge become a monster.

[gboudx]

Update from jeff with the cold part bolded at the bottom:

Compared to last week a much calmer pattern in place.

New surge of high pressure has built down over the region today in the form of another cold front which will help tapper back any sustained warming trend. Next front will cross the area on Thursday keeping the coolish temperatures in place into the weekend. Generally lows will be in the 30’s/40’s and highs near 60 to the mid 60’s this week under mostly sunny skies. Could see some rain off the coast on Thursday night ahead of the next front, but not expecting any of this to reach inland.

Warm air advection begins over the weekend and this will result in a more sustained warming trend with highs pushing the 70’s by late in the weekend into early next week.

For now no significant rain chances are in the forecast through the next 3-5 days. May see better chances of rainfall at some point next week.

Current indications suggest colder air…possibly an arctic air mass may be entering the US near/around Christmas…something to watch.

[Brent]

There are some snowy members on the gfs ensembles a couple big dogs

[Ralph's Weather]

18Z again changes handling of early next week system, it starts it across TX on Sunday then yanks it back to AZ where it hangs out until Tuesday before proceeding across TX.

[cheezyWXguy]

There are some snowy members on the gfs ensembles a couple big dogs

Come on, number 13! I have to work Christmas Eve...

[Brent]

One big storm Christmas Day on the 18z gfs. Plenty of cold around

The Weather Channel's app(i know) has AM Ice Christmas Day in the northern metro, but temps hang closer to climo otherwise