Texas Fall-2015

[Ralph's Weather]

18Z GFS with the Arctic front on Black Friday with an upper low over the SW and a tropical system approaching Mexico. Those ingredients add up to a great chance for winter precip across the state. This run is way too warm behind the front like always.

[Brent]

The LR GFS is a string of wintry threats starting next weekend through the end of the run...

just through 240 hours:



Highs next weekend in the 30s!!! Front plows through Friday afternoon/evening

[srainhoutx]

Evening briefing from Jeff:

Extremely active weather pattern likely over the next 7-14 days.

Strong cold front will sweep across the area early Saturday with rapidly falling temperatures during the day.

Potential arctic air outbreak the weekend after Thanksgiving

If we thought the last few weeks were active…hold on! Upper air pattern will undergo strong amplification with cold arctic air mass currently over Alaska becoming increasingly dislodge and sent southward. A piece of this air mass will arrive this Saturday before potentially the entire air mass dumps down the front range of the Rockies just after Thanksgiving.

Moisture return is underway this afternoon and expect clouds to develop from south to north tonight. Moisture increases more on Friday and weak isentropic lift is expect to help force a few showers by afternoon. Strong cold front will blast into TX Friday night and move off the coast between 600am and noon on Saturday with temperatures falling from the 60’s into the 40’s with very strong north winds. Expect strong lift with the front to produce numerous showers and even elevated thunderstorms Friday night. Models continue to trend wetter and wetter with this system and now show possibly 1-2 inches of rainfall across the region especially in areas of banded heavier thunderstorms.

Big news will be the temperature fall as cold Canadian air mass slices into the region. NW winds post front will howl with impressive 5-7mb pressure rises over the region as large 1043mb high pushes down the plains into OK. Expect winds on Saturday sustained of 25-35mph with gusts of 40-45mph which will drive wind chills into the lower 40’s and 30’s. Gale Warnings will be needed for most if not all waters as the cold air mass strikes the warm waters…expect gusts to 50mph or even greater offshore into Saturday night. Skies will clear rapidly Saturday afternoon and this will result in temperatures falling into the 30’s for most locations Sunday morning. Think winds will stay up enough to prevent a freeze for most areas…but N and W areas could be close.

Cool on Sunday with highs only in the mid 50’s even with much sun. Big concern is Monday morning with clear skies and calm winds along with dewpoints in the upper 20’s. Looks like we may see a widespread freeze north of I-10…which would require a freeze watch since it would be the first killing freeze of the season. Areas north of HWY 105 look more certain to have a freeze and will need to take the needed precautions with respect to tender vegetation.

Monday-Thursday:
Southerly flow to return to the region with active sub-tropical jet overhead. Clouds will increase late Monday…and do not expect the sun for the next several days after that. Will bring rain chances into the forecast Tuesday-Friday, but certain days will have better chances as disturbances move across in the sub-tropical flow aloft..it will not rain the whole time…but there will be periods of rain and thunderstorms. Temperatures will be mild as southerly flow is maintained with lows in the 50’s and 60’s and highs in the 70’s.

Long Range (Black Friday-weekend after Thanksgiving):
Upper air pattern undergoes strong amplification with massive forecasted 1058mb arctic high pressure cell dropping southward out of NW Canada. Cold arctic air mass looks poise to tumble down the plains and through TX with very cold temperatures. EPAC tropical cyclone looks to be drawn NE into this very cold air mass (I have never seen an EPAC tropical system be pulled over an arctic air mass) with all kinds of precipitation. Forecast profiles are all over the place between models and model runs, but intensity of cold air mass would likely result in some degree of P-type considerations across portions of TX. This is still a good ways off and subject to significant changes over the next several days…but something to certainly be watching.

[Ntxw]

This is very high confidence from the CPC on a wet pattern.



Beyond the coming period latest Euro weeklies shows El Nino's classic split flow pattern for the first couple weeks of December. Higher heights and warm above, cold undercutting storms below from the southwest to Southern Plains.

[Rgv20]

12zECMWF Ensemble Member #50 has a lot of snow for Northern Mexico and the Deep South Texas in the 9 to 10 days.....Its the only one showing that for the RGV Interesting pattern setting up for next weekend! Alot of model watching coming up!

[Brent]

Pete Delkus just threw out a teaser for the day 9-10 storm "some snow flakes are possible as we approach December" or something. I was surprised he mentioned it and I don't even usually watch WFAA either.

[dhweather]

This is very high confidence from the CPC on a wet pattern.

http://i66.tinypic.com/21o27t4.gif

Beyond the coming period latest Euro weeklies shows El Nino's classic split flow pattern for the first couple weeks of December. Higher heights and warm above, cold undercutting storms below from the southwest to Southern Plains.

[dhweather]

Pete Delkus just threw out a teaser for the day 9-10 storm "some snow flakes are possible as we approach December" or something. I was surprised he mentioned it and I don't even usually watch WFAA either.

It's scary how consistent the GFS has been with this. 8-9 days ago it was eluding to some cold air right on or after Thanksgiving, and it really hasn't deviated from it. Euro seems to be on board as well.


But before that, FROST/FREEZE likely for a good chunk of North Texas on Sunday morning. Plants and pets, and while you are at it, go ahead and get the pipes ready too. Exactly what I did this evening.

[Brent]

Pete Delkus just threw out a teaser for the day 9-10 storm "some snow flakes are possible as we approach December" or something. I was surprised he mentioned it and I don't even usually watch WFAA either.

It's scary how consistent the GFS has been with this. 8-9 days ago it was eluding to some cold air right on or after Thanksgiving, and it really hasn't deviated from it. Euro seems to be on board as well.


But before that, FROST/FREEZE likely for a good chunk of North Texas on Sunday morning. Plants and pets, and while you are at it, go ahead and get the pipes ready too. Exactly what I did this evening.

Steve McCauley also threw out a teaser mentioning questions about frozen precip

It is hard to ignore the consistency though and as I recall last November's snow was strongly hinted at more than a week out...

[SouthernMet]

[JayDT]

Ohhh wow!! That looks very interesting

[Brent]

The 0z GFS stalls the front and keeps the cold air in Oklahoma for most of the precip and keeps it rain for most of us... and its a LOT of rain... over 7" by the 30th at DFW.

Bottom line... a lot of precip on the way...

CMC temps during that storm would be a disaster:

[TarrantWx]

CMC temps during that storm would be a disaster

That really would be a disaster. CMC shows 36+ hours of ice/sleet falling into temperatures in the low 20s with QPF around 2". Goodbye power...

The difference in the GFS solution today I think is due to its position of the ridge in NW Canada versus last night's 0z solution of a classic -EPO over Alaska. That's also the solution that the Euro was showing for the last 2 runs (and maybe more, I only started checking last night). The 0z GFS tonight seems to handle the 500mb pattern very strangely. Last night's run showed the 500mb ridge building into Alaska, moving East into NW Canada while strengthening, and then retrograding and strengthening even further over Alaska. Tonight's run shows the weak ridge into Alaska, moving into NW Canada strengthening a little, and then almost falling apart. I suspect it has something to do with features over the Pacific which will obviously give the models fits until a day or two before the event due to lack of upper air data.

Needless to say, it should be a very fun week of model watching. I'm trying not to get my hopes up quite yet.

[gpsnowman]

Last "warm" morning for a while. Going to work Sunday morning is going to be cold. Finally!! Cant wait to see what happens after Thanksgiving.

[Ralph's Weather]

I am still in favor of the colder solution, but we will have to see if the -EPO does develop as that will determine everything. Regardless of temps though next weekend looks very wet.

[TheProfessor]

Looks like it might stay below freezing all day Sunday here. And the 0z CMC run really does not want me to take my 3rd Calculus Midterm. If the run verified (really hoping it doesn't because 2013 wasn't fun anyway) it could rival 2013's Ice storm.

[TheProfessor]

0z CMC also has a major Black Friday Ice storm for me in Kansas, might take us double the time to get back home on that Saturday oh goody That's IF that run verfied of course lol.

[gboudx]

Good thing those graphics SouthernMet posted are over a week out, because that's about the ugliest forecast I've seen. Power outages lasting a long time almost a sure bet. Just ugly.

[BigB0882]

Just what I feared. Something keeping that cold air from moving East into Louisiana. I hope this pattern doesn't lock in all winter.

[wxman57]

Last few runs of the GFS (and 00Z Euro) keep the snow out of NE TX over the next 10 days. Some snow for the Panhandle, but that's about it. May still be a bit early to start thinking frozen precip in the D-FW area.