Texas Winter 2014-2015

[TheProfessor]

Pay attention to the Dew points in the Metroplex, they will likely dictate the temperatures that will occur here, right now the dew point here is 29, if that doesn't change then it could spell trouble here.

[SouthernMet]

Case in point, the furthest the models have the freeze line currently is Lubbock-OKC... When in reality the freeze line is Nocona - Jacksboro - Cisco line.

[WeatherNewbie]

In my amateur opinion, the Metroplex is going to be below freezing for a good chunk of this event. The question will be how much and where the precipitation falls. For the sake of all the drivers, I hope it stays mostly west of I-35 as they are predicting.

[Lagreeneyes03]

It is significantly colder to both the north and west of the Metroplex... that is a pretty good indication that the Metroplex is headed for colder temperatures. The Metroplex was able to hit near its forecast high today because the sun broke through. Once the colder air and clouds push in this evening, I think you are going to see a bust on the Metroplex temperatures going forward.

Thank you...

I hope ya'll are right. I know it's much colder than originally progged closer to the core. A friend of mine in Lincoln NE was talking a few days ago about how the low was forecast to be 12 degrees last night. Well it was actually zero.

[Tammie]

So the dew point in Denton is 27 with a temp of 43. Low temps tonight predicted to be 28. How does the dew point correlate to freezing temps or freezing precip?

[SouthernMet]

The biggest busts are in the Panhandle where temps are 5 to 10 degrees colder than the 18Z runs predicted and in parts of E TX where cloud cover has been stubborn. A 5 degree bust NYD morning will have a huge impact. Tomorrow we will enter the range of the short range models and that will give us a better idea.

18z gfs has childress at 31, its 20 in childress.
18z gfs has temps at 37 in abilene, its 27 in abilene.

pretty big busts elsewhere too

[srainhoutx]

Word to the wise...the guidance is flip flopping every 6 hours and that should continue right up to the event that is expected Tomorrow into New Year's Day. Case in point, the latest storm track shifted 600 miles to the S today. Yesterday afternoon the low track was expected to be across NW New Mexico into Southern Colorado. This afternoon the low track has shifted to SE Arizona to Northern Mexico. Time to start watching the radar and satellite imagery and surface temperatures upstream....

[weatherguy425]

Case in point, the furthest the models have the freeze line currently is Lubbock-OKC... When in reality the freeze line is Nocona - Jacksboro - Cisco line.

18z NAM initialization and forecast valid for 3 PM (an hour ago) isn't doing too bad. Still, I would not call this a major bust by any means. But, as many including yourself have mentioned, this is certainly a now-casting scenario... as many winter weather events in Texas are.

[SouthernMet]

Case in point, the furthest the models have the freeze line currently is Lubbock-OKC... When in reality the freeze line is Nocona - Jacksboro - Cisco line.

18z NAM initialization and forecast valid for 3 PM (an hour ago) isn't doing too bad. Still, I would not call this a major bust by any means. But, as many including yourself have mentioned, this is certainly a now-casting scenario... as many winter weather events in Texas are.

http://www.tropicaltidbits.com/analysis ... s=392.7273

[weatherguy425]

Case in point, the furthest the models have the freeze line currently is Lubbock-OKC... When in reality the freeze line is Nocona - Jacksboro - Cisco line.

18z NAM initialization and forecast valid for 3 PM (an hour ago) isn't doing too bad. Still, I would not call this a major bust by any means. But, as many including yourself have mentioned, this is certainly a now-casting scenario... as many winter weather events in Texas are.

http://www.tropicaltidbits.com/analysis ... s=392.7273

^Right. Panhandle temperatures were modeled too warm. A function of a colder air-mass or dense low-level cloud cover? I'm thinking the latter. And, current temperatures and current freeze-line are not too far off from forecasted data. Still, much can change between Abilene and DFW. Not trying to diminish the threat, but rather home-in on what may actually be causing these initialization issues.



Edit to add LINK: http://wx.hamweather.com/maps/currents/ ... ntral.html

[SouthernMet]

Weatherguy, freeze line is Nocona - Jacksboro - Cisco line.

[Ralph's Weather]

http://www.tropicaltidbits.com/analysis/models/?model=rgem&region=us&pkg=mslp_pcpn_frzn&runtime=2014123018&fh=39&xpos=0&ypos=483.6364

This + subfreezing temps = you do the math.

The RGEM has shown this for the last couple runs and it makes sense looking at conditions upstream. Its freezing rain accumulation maps show up to an inch in the Metroplex and major accumulations from Big Ben to Northeast Texas. And even it has current temps 10 degrees too warm behind the Arctic front. It begins the precip before midnight, the NAM begins it around 3AM and the GFS around 6AM those timing differences will have a big impact as midnight through about 9AM will have the lowest temps.

[gatorcane]

The 12Z ECMWF still does not penetrate the really cold anomalies into Central or East Texas. It's like they hit a wall and don't progress east as the airmass quickly modifies. See images below. 24 and 48 hour images below. This model has been very consistent with this:

[SouthernMet]

Weatherguy, the link you posted appears to not have accurate temps. All reports/weatherstations im seeing out of the Abilene area are showing 26-27 degrees, not 30.

Also it shows Vernon @ 30 & Vernon is reporting 20.

[weatherguy425]

:uarrow: Weatherguy, freeze line is Nocona - Jacksboro - Cisco line.

Which is not too far from forecasted time-frame. Not noticing a huge difference...

18Z 4k_NAM valid at 21z (3 PM) below

Link: http://www.tropicaltidbits.com/analysis ... 0&ypos=432

Again, I don;t mean to knit-pick the fine details. However, if we're discussing the location of the 'freeze-line' and associated Arctic cold front, initialization was not terrible. Look further up-stream... temps are not busting too terribly. The 'bust' across the panhandle is more of a localized phenomenon as up-slope flow has created dense low-level cloud cover and freezing drizzle... keeping temperatures under guidance with lack of any clearing.

[ronyan]

Again, those are 850mb temps on the Euro. I don't think the Euro surface temps are publicly available though, but basically all models have been showing that pattern with the coldest anomalies staying in W TX and over panhandle.

[SouthernMet]

:uarrow: Weatherguy, freeze line is Nocona - Jacksboro - Cisco line.

Which is not too far from forecasted time-frame. Not noticing a huge difference...

18Z 4k_NAM valid at 21z (3 PM) below

I strongly disagree, lets take this to pms.

[SouthernMet]

Freeze line has now reached Alvord- PK Lake- Eastland line.

[Portastorm]

Word to the wise...the guidance is flip flopping every 6 hours and that should continue right up to the event that is expected Tomorrow into New Year's Day. Case in point, the latest storm track shifted 600 miles to the S today. Yesterday afternoon the low track was expected to be across NW New Mexico into Southern Colorado. This afternoon the low track has shifted to SE Arizona to Northern Mexico. Time to start watching the radar and satellite imagery and surface temperatures upstream....

Yes sir. The AFDs out of Lubbock and Amarillo this afternoon but reference the fact that guidance is now all over the place on what happens with the upper low and how quickly it ejects out into the central CONUS.

[aggiecutter]

Shreveport AFD: Really going to be a tough call on Thursday. A degree or two one way or the other will make a big difference in precipitation type:

"BY DAYBREAK...TEMPERATURES
ACROSS NORTHEAST TEXAS...PORTIONS OF SOUTHEAST OKLAHOMA...SOUTHERN
ARKANSAS...AND NORTHWEST LOUISIANA WILL BE BELOW FREEZING.
QUESTION IS WHETHER TEMPS WILL CLIMB ABOVE FREEZING BEFORE ONSET
OF PRECIPITATION"