Texas Winter 2013-2014

[Texas Snowman]

@RyanMaue: GFS 18z was only a bit warmer for Dec 7, 2013 12z -- with CONUS spatial avg of 18.2°F = lowest 5% of coldest December days in past 34 years

[Texas Snowman]

@RyanMaue: November CONUS temp drop from 50° to 30°F impressive -- 20°F drops are rare & should be studied for cause/impacts http://t.co/v415dnR6zO

[TeamPlayersBlue]

The GFS was under initializing it BIG TIME this morning. I havent looked at the 18Z though. Not sure how much of a difference that will make.

I think you are right that will make little to no difference in the grand scheme of things. Maybe a small extra push for the cold air surging south, but otherwise, no real difference. I do like seeing these arctic highs build up (especially the late winter season ones where the highs can push 1060mb to 1070mb in Canada).

I think if you look closely at the map you posted, you can see 1060MB isobar.

[Texas Snowman]

OKC TV met Gary England:

"@garyeOK: Okla: Big time Arctic cold arriving Wed. Hide the women and children and put the animals in the barn! Ice & Snow too."

[Ntxw]

After going through the Ensembles and OP guidance, I've come to some thoughts for this evening.



Said cold air mass is now building over the Yukon. This region of anomalous cold is smaller (in comparison to what's coming down the road). This is our weekend cold snap. It's cold, it will push and be entrenched. While this is going on, a second ingredient is in the works in central Canada which is the displacement of the Polar Vortex to Hudson bay or to the west. This is when the truly brutal cold air mass will settle in the far north, worthy of the coldest mid winter periods. The Northeast Pacific ridge is going to rip chunks of it down in what is a series of fronts. How many, I can't say for certain at this time but between now and the 20th of December expect them.

As the AO begins to lower and the Pacific continues ridging from the Aleutians in time the PV will make it further to the south. This is the uncertain period the week of the 15th-22th, if we see the PV sink to very low heights there is a good chance on the other end we may see some mind numbing cold enter the CONUS. I am still following the EPO index closely, what happens the rest of this week will be very telling of how cold it's going to get.

[BigB0882]

Ntwx, do you see this really cold air ever getting further south and east? Or do you continue to see it being stuck in the west and central CONUS? Just curious for my neck of the woods but also I plan on going to NYC for Christmas so curious if any major outbreak may affect that far East or not.

[Ntxw]

Ntwx, do you see this really cold air ever getting further south and east? Or do you continue to see it being stuck in the west and central CONUS? Just curious for my neck of the woods but also I plan on going to NYC for Christmas so curious if any major outbreak may affect that far East or not.

I don't know about past week 2. But the core of the cold anomalies (greater than 2SD's) will be in the inter-mountain west and the great plains. It will bleed east and southeast but it's more peripheral cold that way. The reason is the NAO and AO are positive (and have been extremely positive.) The closer you are to the Atlantic the less likely you will get effected as much. The show is being run by the Pacific, eventually it may get cold enough to overwhelm the pattern but that's a low confidence forecast being longer out.

[Portastorm]

Ntwx, do you see this really cold air ever getting further south and east? Or do you continue to see it being stuck in the west and central CONUS? Just curious for my neck of the woods but also I plan on going to NYC for Christmas so curious if any major outbreak may affect that far East or not.

There's actually chatter on some other forums which focus more on Eastern US weather that the -EPO signal may overpower the +AO ... then look out East Coast! There's definitely a distinct possibility that the NE gets its turn later this month.

But ... I'm not Ntxw ... but I did stay at a Holiday Inn Express last month!

[sooner101]

Do you guys think this front/storm system will be more intense than the one last week?

[TeamPlayersBlue]

Looks identical as of now, if anything a bit weaker. The next one after this weekend looks more potent. These shallow air mass storms are driving me crazy though.

[South Texas Storms]

How's it looking precip. wise throughout the rest of December Ntxw? I noticed that the SOI has risen quite a bit throughout the past week so it doesn't look like that is in our favor for precipitation in the short-term. Any signs of a wet end to the year during the second half of December?

[Portastorm]

Do you guys think this front/storm system will be more intense than the one last week?

I'm not sure what you mean by "intense." It appears right now that this weekend's system may be similar in temps to last weekend's system but have less precip. But it's still early on and if a coastal low develops along the Texas coast or if some energy remains backed off to our west/southwest ... that could quickly change things. I'm not confident that the GFS has a good handle on temps so I'm not willing to commit to a precip type across Texas for the weekend. Not yet at least. Upper-level energy is another question. Right now the GFS is suggesting that upper-level energy will not traverse across the Plains as deep as it did two weekends ago. That could mean a better threat for wintry precip for you in Oklahoma.

To me, the biggest headline here is that we're entering into a pattern of several weeks of cold snaps which may get progressively more severe. Everything from the teleconnections to the longer-range models support that idea. How the details play out may be a short-term game for all of us where we don't know details until 72 hours prior to an "event."

Sorry I'm not more definitive but that is the honest take tonight from the PWC.

[Ntxw]

How's it looking precip. wise throughout the rest of December Ntxw? I noticed that the SOI has risen quite a bit throughout the past week so it doesn't look like that is in our favor for precipitation in the short-term. Any signs of a wet end to the year during the second half of December?

I think you pretty much nailed it there. 30 day SOI is very positive and we haven't seen any big crashes. It takes a week or so for things to take hold using SOI, taking into consideration the MJO will not be in the wet phases either. The cold air ontop of that will likely prevent any kind of meaningful moisture return before month's end, gulf flow will be limited. In terms of total QPF we will probably be below normal.

[South Texas Storms]

How's it looking precip. wise throughout the rest of December Ntxw? I noticed that the SOI has risen quite a bit throughout the past week so it doesn't look like that is in our favor for precipitation in the short-term. Any signs of a wet end to the year during the second half of December?

I think you pretty much nailed it there. 30 day SOI is very positive and we haven't seen any big crashes. It takes a week or so for things to take hold using SOI, taking into consideration the MJO will not be in the wet phases either. The cold air ontop of that will likely prevent any kind of meaningful moisture return before month's end, gulf flow will be limited. In terms of total QPF we will probably be below normal.

Hopefully the SOI can crash soon so that we can get some more moisture and disturbances to interact with the cold temperatures throughout the next several weeks. Porta and I are due for a Christmas snow miracle!

[Portastorm]

Hear! Hear! South Texas Storms ... yes!!

You know lads (and lasses), they say the NAM is the last refuge of weather scoundrels. And here I am looking at the 0z NAM before I shut it down for the night. At the end of the run it shows freezing rain pretty much on top of Austin (12z Friday ... 6 am). Srainhoutx mentioned to me a bit ago that the SREF and NAM have quicker movement and deeper movement on the front late this week. Sound familiar?

Stay tuned ... and stock up on your Grey Goose!

[South Texas Storms]

Tonight's 0z GFS looks colder this weekend and is now showing freezing rain as far south as Austin and San Antonio on Saturday.

[Portastorm]

One final fun tidbit before I click "Shut Down Windows" ... you Metroplexers should check out Ryan Maue's tweets tonight. He just posted the GFS for Friday night and said it could be quite a mess in DFW with mixed wintry precip and "heavy" too.

[sooner101]

From Steve McCauley's facebook page tonight:

I just ran the latest stat method, and it is now up to 95% probability of ice coming to north Texas Thursday night into Friday morning.

Again, I want to emphasize that this is NOT like the last storm where we had to predict the final temperature to within 1 degree to determine precipitation type. That event was always a borderline rain/ice situation depending on which way that 1-degree difference in temperature went. SOME Metroplex locations saw ice while ALL locations saw rain which melted the ice and made for just wet roads.

This coming storm is altogether different. For the past few days, the Stat Method has been leaving little room for doubt that ALL areas of the Metroplex will drop BELOW freezing Thursday night into Friday morning. And this will happen as the rain continues to fall. As the rain hits exposed objects below 32 °F, the raindrops will freeze on impact and will entomb them in a sheet of ice.

But the question remains: just how thick will that sheet of ice end up being? Will it be just a thin film found sporadically here and there that will just cause a few fender benders, or will it be a widespread thicker layer that will send most cars into a tailspin as they try to negotiate the High Five?

We will be able to determine the answer to this more precisely once we are within 24 to 36 hours of the winter storm's arrival! -sm

[srainhoutx]

Tonight's 0z GFS looks colder this weekend and is now showing freezing rain as far south as Austin and San Antonio on Saturday.

The GFS is also 'sniffing' out a Coastal trough/low near Corpus that had not been seen so far via that model. The 12Z Canadian did show that feature and if it does develop it would certainly enhance precip across Central/SE Texas Saturday into Sunday as the 500mb trough and associated short wave passes across the Panhandle.

[orangeblood]

Anyone looked over tonight's Crazy Uncle Model (Canadian), goes into extreme mode with below 0 F temps into North Texas next Wednesday morning. Also shows a decent winter storm into southeast Texas early next week. Been a long time since I've seen a model go to that extreme across Texas.