Texas Winter 2013-2014

[Ntxw]

What is that from? That shows frozen rain for us in SELA and I didn't think our temps were going to get close to freezing. It is for Dec 10, which would be the next dose of cold air? I doubt it happens but interesting to see. I figured because of the ridge we would stay quite warmer than you guys in TX.

Upper level low, not unlike the one that came through thanksgiving week

[BigB0882]

I thought ULLs usually result in a colder air column from top to bottom, typically resulting in more snow than frozen rain. You can still have big pockets of warm air above the service with an ULL passing over?

[Ntxw]

I thought ULLs usually result in a colder air column from top to bottom, typically resulting in more snow than frozen rain. You can still have big pockets of warm air above the service with an ULL passing over?

Well the GFS actually moves the ULL further north so it's mostly overrunning but you never know with those things. They usually go further south than predicted and create forecasting nightmares. SE TX/SW LA is ULL/coastal train capital of the south it seems

[TheProfessor]

Even if the rain falls before the freeze like the tech model predicts. Wouldn't all that water freeze over the roads causing similar problems?

[gboudx]

I've been following Steve's posts and it seems like he's discounting the TT model. For the last event(non-event), his Stat method correctly forecasted the cold rain most of the area experienced. For this event, it's all in on freezing rain and sleet with severe impacts.

[katheria]

I've been following Steve's posts and it seems like he's discounting the TT model. For the last event(non-event), his Stat method correctly forecasted the cold rain most of the area experienced. For this event, it's all in on freezing rain and sleet with severe impacts.

yep i agree with you....... just called family and told them to cancel coming up this weekend from the Houston area, rather them be safe, we can always get together another weekend

[TrekkerCC]

I thought ULLs usually result in a colder air column from top to bottom, typically resulting in more snow than frozen rain. You can still have big pockets of warm air above the service with an ULL passing over?

Well, you will have cooling due to the upper level system coming in at the mid-levels. However, the depth of cold air near the surface is very shallow. There will be a warm tongue at about 5,000ft in the air. When you have very dry atmospheric column and then precipitation falling into it, you can get cooling due to the effects of evaporation of precipitation in very dry air. However, the column will already be saturated from the top down and little or no evaporative cooling will take place, so no cooling from evaporative processes will occur to cool the "warm nose". The cold at the surface will come from cold air advection, or transport of cold air from the north and west(due to the winds). Due to the warm air nose around 5,000ft that will be above freezing, it will melt all the precipitation to liquid form. We will get re-freezing of the precipitation before it reaches the surface or "sleet". Before the transition to sleet, the rain will freeze on contact or more commonly know as freezing rain. It is very unlikely, but possible, that we might transition to some light snow on Sunday. Models are keeping us all sleet during the weekend, but if the cold air gets deeper and erodes the warm nose over the weekend and if the models are underestimating the depth of the cold air, we might go over to snow at the very end. However, expect mostly ice from either freezing rain or sleet throughout this event.

[KatDaddy]

Strong cold to push into SE TX tomorrow morning and across Houston Metro around noon time with temps in the 40s by the evening. Rain will accompany the front with a few thunderstorms.
Winter precip is still possible along and N of a Brenham to Conroe to Livingston line per Houston-Galveston NWS. Houston Metro and points S look to have only a nasty cold rain. The real concern for Winter precip remains across North Texas where Winter Storm Warnings, Winter Storm Watches, and Ice Storm Warnings have been issued. Winter precip will be possible from tomorrow night through Sunday across North Texas. Be ready for a dramatic weather change tomorrow. Glad I got the Christmas lights up this evening.

[joshskeety]

Even if the TT on the last storm was waaaaaaaay wrong.. Not sure why it would be getting any credit.. Reality was we saw a lot of freezing rain in that storm out here in Parker county and according to it we would have been 40 degrees and cold rain. Damn thing was 10 degrees off.. HERE... It had DFW in the low 40's..

[gboudx]

Steve doesn't seem like he's giving it much credit. He said for completeness he was mentioning it. I like that he mentioned it instead of just ignoring it and keeping the info from the people who follow him on FB.

[katheria]

yep i totally agree. i really miss him on the news.
he always looks at all sides and doesn't sugar coat things and says it as he see's it

giving up some sleep tonight to stay up for the model runs

[Ntxw]

yep i totally agree. i really miss him on the news.
he always looks at all sides and doesn't sugar coat things and says it as he see's it

I agree with you here, I miss seeing him on the news. The best forecasters are more than just those who tell us predictions, they are also great teachers of weather and he is one of those. I'm not old enough to be around for Harold Taft but from everything I've heard he was one also.

[katheria]

I was younger but i still remember Mr. Taft thats for sure

i still have his book "Texas Weather"

[Ntxw]

The NAM's QPF is still in question for DFW, but it's not very far from a very heavy liquid equivalent, mesoscale and shifts of a couple of miles makes a big difference on that model. The silver lining is it keeps DFW in more sleet.

[iorange55]

The NAM's QPF is still in question for DFW, but it's not very far from a very heavy liquid equivalent, mesoscale and shifts of a couple of miles makes a big difference on that model. The silver lining is it keeps DFW in more sleet.

Yeah, hard to nail down exactly where the heaviest precip will be, but we're close enough to be on alert. I'm still holding out hope for a mostly sleet event.

*fingers crossed*

[katheria]

The NAM's QPF is still in question for DFW, but it's not very far from a very heavy liquid equivalent, mesoscale and shifts of a couple of miles makes a big difference on that model. The silver lining is it keeps DFW in more sleet.

Ntxw whats it showing for QPF?
im soo tired i cant even read the Nam model lol its blurring together

[Portastorm]

I thought ULLs usually result in a colder air column from top to bottom, typically resulting in more snow than frozen rain. You can still have big pockets of warm air above the service with an ULL passing over?

Well the GFS actually moves the ULL further north so it's mostly overrunning but you never know with those things. They usually go further south than predicted and create forecasting nightmares. SE TX/SW LA is ULL/coastal train capital of the south it seems

Just to add something ... I think it is also important to point out that often in winter in Texas when an upper-level low traverses the state, we see coastal surface low development somewhere off the Texas coast. Sometimes those coastal lows, if close enough and if the boundary layer temperatures (surface temps) are cold enough, can produce wintry precip in south central, east central, or southeast Texas. Seen it happen a number of times over the years.

[joshskeety]

It is a tad further north than the 18z run.. The dry slot is actually just north of the Metroplex it seems rather than it being right over the Metroplex like before.. Its almost a spitting image of what it looked like in the last storm minus temps of course.. Using the last storm it showed the Metroplex just north of most of the QPF, but in the end the Metroplex got much more and there was much more moisture to work with.. Like last time we will just have to see what the GFS says since it has been the most consistent on this so far and how well it did with the previous storm..

[joshskeety]

Shows about .25-.3 QPF in the metroplex.. About 10% more than the last run...

[Portastorm]

Shifting the focus on the 0z NAM run down south a little, I'm noticing it's a bit colder and wetter for south central Texas. Not only is the expanse of freezing rain a bit larger on Friday morning for my area but the NAM pops up freezing rain again Saturday morning and the 18z and 12z NAM runs weren't nearly this aggressive in this area. Should be interesting to watch if it is an anomaly or a model trend.