Texas Winter 2016-2017

[Brent]

The GFS mean is very bullish for being 6 days out... widespread snow in most of the state(even Austin/Houston get a little), several inches around DFW

Euro is rolling

[Brent]

0z Euro

Precip already breaking out Wednesday afternoon at DFW with temps just above freezing

Temps falling below freezing Wednesday Night after a little precip

Euro is dry through Thursday Evening otherwise and getting colder

[Ntxw]

Euro is going to be another cold run

[Brent]

yep, storm is suppressed down below Austin basically

(Daytime high) Wednesday mid 30s, high Thursday would be maybe 33-34, Friday probably around 30, Saturday around 32. The run ends with a high around 40 next Sunday lol

[TheProfessor]

0z GFS-Para would be awesome if the storm were not to dig so much, would be great if it moved east to east northeast after it enters South Texas instead of continuing to dig deep into Mexico. Good thing is that for me at least storms have had northward trends as events get closer, of course you don't want too much of a northward trend.

[TheProfessor]

Looking at the 0z Navgem it would be nearly perfect, especially if the cold air arrived a little bit earlier. However from what i've heard the Navgem is usually more progressive which could mean it might not be digging the storm enough due to less blocking. JMA looks like a dud precip wise.

[gpsnowman]

Steve McCauley seems to be on board with at least some winter precip according to his last FB post. Amounts and location still up in the air this far out of course.

[CaptinCrunch]

An Arctic cold front will arrive early Wednesday and bring another blast of cold air to the region. After the cold air arrives, an upper level disturbance will approach from the west and bring a chance of winter precipitation beginning Wednesday night and ending from west to east Friday. The best chance for winter precipitation will be on Thursday. At this time it appears that a mix of rain and freezing rain will begin in the north Wednesday night with a chance of a sleet/snow snow mix in most areas Thursday into Friday. Accumulations should be light. Since this potential event is still several days away, check the forecast often through next week for refinements.

For New Years Day (Sunday), It looks like the weak front may
actually stall somewhere over the forecast area as the Pacific
Northwest shortwave dives all the way southward into Northern
Mexico. This system will provide strong forcing for ascent as it
swings east across Texas and the Southern Plains Sunday Night.
Being that the system will move through late in the evening and
overnight, surface-based instability will be marginal at best.
However, elevated instability when coupled with the strong
(40-50KT) bulk shear values should be sufficient for at least
isolated thunderstorms. A few strong storms with small hail and
gusty winds will be possible, but at this time the severe weather
threat seems pretty low.

As showers and storms shift east into the MS Valley early next
week, the focus will shift to another Arctic blast mid week and
the possibility of some wintry precipitation during the second
half of the week. Model guidance is in relatively good agreement
regarding the arrival of the front (Tuesday night) and the
significantly colder air behind it. Discrepancies, however, exist
regarding the amount of moisture and lift which will occur as a
series of disturbances propagate around the base of a deepening
longwave trough over the CONUS. The ECMWF continues to keep all
precipitation limited to coastal areas of TX where the better
moisture resides, keeping North and Central Texas dry and cold.
The GFS, on the other hand, is more aggressive with isentropic
ascent and the resulting precipitation. Being that it is still a
good ways into the future, the forecast will indicate at least a
chance of rain and freezing rain Wednesday night, transitioning to
mainly snow on Thursday as the cold air deepens. But with the
amount of moisture and strength of lift remaining a question mark,
we will keep precip light and snow/ice accumulations minimal.

[wxman57]

I think wxman57 might get some ice pellets along his bike route...

That would be impossible, as my bike route won't leave the inside of my house. I notice that the 00Z Euro backed off from forecasting any snow in Texas, by the way. I'm staying in Houston THIS time, so I'll be fighting this cold invasion all the way!

[dhweather]

First and foremost, I hope everyone had a Merry Christmas, and has a great start to the upcoming New Year.

Next week looks interesting. Cold for sure, the nagging question is available moisture and lift. It's really hard to get both of those at the same time in Texas.

[bubba hotep]

The 00z Euro package was pretty encouraging for us here in the DFW area. The op had some changes that I liked at H5 and it appears to be the dry outlier with both the EPS mean and control being wetter. About 30 of the EPS members showed some variation of winter weather in DFW.

[TexasF6]

Just watched the Daily Update with Bastardi, he says the models saying warm for the second week of January are WRONG!!! He expects the blocking pattern to hold, and all of North America to be cold. He saying its model feedback causing the GFS to blunder. The surprise in his brief was Europe geting buried in snow for me. He also said North Asia would reload with cold.....But, I think the info on this board has been saying these things for awhile. Looks like Joe reads our boards (haha). I expect announcements in the coming days and a press briefing from the Scenic SW Side of Austin in the future....

[bubba hotep]

That's a really good point. I like that 500mb map, especially that GOA/Alaskan ridge. Think we've seen it before.
http://i68.tinypic.com/2ij57ox.png

Block in the North Atlantic looks better this round though.

That event was associated with a big -EPO and the MEI was slightly negative during that period, it would be in my analog mix.

[ronyan]

The -EPO forecast for this event would exceed Dec 2013 by a little, about -380 forecast on Jan 3rd. That has been trending lower, soon it will get into some rare territory.

[Portastorm]

Just watched the Daily Update with Bastardi, he says the models saying warm for the second week of January are WRONG!!! He expects the blocking pattern to hold, and all of North America to be cold. He saying its model feedback causing the GFS to blunder. The surprise in his brief was Europe geting buried in snow for me. He also said North Asia would reload with cold.....But, I think the info on this board has been saying these things for awhile. Looks like Joe reads our boards (haha). I expect announcements in the coming days and a press briefing from the Scenic SW Side of Austin in the future....

This photo, taken this morning somewhere in southwest Austin, has gone viral on social media as a number of these trucks are reportedly lined up at the gates of the Portastorm Weather Center:

upload img

Meanwhile, the overnight AFD from the NWS Austin/San Antonio office I think reasonably handles the expectations for next week. Here is a snippet:

An amplifying ridge into Alaska and western Canada Monday and
Tuesday and deepening trough axis over the western and northern
CONUS will allow for a surge of arctic air to move southward
early in the week, arriving into South-Central Texas on
Wednesday. There is quite a bit of uncertainty with temps and
precip chances across the CWA Thu-Fri (Day 7-8) behind the arctic
front. A rather large spread in GFS and ECMWF ensemble members
exists with respect to both temps and QPF. Extreme caution should
be given to any one run of a particular model this far out with
respect to precipitation chances and winter precip type this far
south. Nevertheless, we will closely monitor the many more models
runs to come through the weekend and into early next week for
possible introduction of some type of mix of wintry precip, should
models converge that way.

[Ntxw]

While wxman57 is correct in that the euro OP was a dry, cold run what I find encouraging (via wxbell models page) that the ecmwf ensemble package is decent. Several members do have something.

Just a few more days of runs and we can go from slim chance, to slight possibility! GFS is rolling now

As for long range, I think it will relax mid month, its hard though to see the kind of December relax with the AO/NAO not strongly positive in record territory. Neutral to slightly negative. It will hang whatever cold around a little longer and subdue warmups. We did have some -AO/NAO in November but there was no cold air to keep around, might be a little different this time.

[gboudx]

Update from Jeff. Only the part concerning next week is shown.

Wednesday-next weekend:
Upper level pattern across much of the US will undergo amplification with strong ridging developing well into Alaska and also across Greenland resulting in high latitude blocking with a trough across much of the US. Cold arctic air mass will be gathering in NW Canada and begin to move southward into the Rockies by early next week. Position of the trough developing across the US is not overly favorable for arctic air to blast southward, but instead ooze south under its own density with fairly zonal flow across much of the US. Arctic front should arrive across TX on Wednesday and surge off the TX coast late Wednesday with temperatures falling quickly behind the front on Wednesday into the 40’s and 50’s. This pattern also favors a low latitude storm track where moisture overruns the surface cold air and can lead to southern plains and southern US winter weather events.

Questions then turn to just how cold will this air mass be and when/how much precipitation falls in the post frontal cold air Thursday and Friday. At this point there are many questions regarding the depth of the cold air, how cold the surface layer is, is the air mass too dry to support precipitation, and if in fact precipitation does occur in what form which depends on the surface and mid level temperature profiles.

At this point will go with temperatures in the upper 30’s and low 40’s on Thursday with “liquid” rain for all areas of SE TX…Thursday night into Friday morning looks to be a critical time period where surface temperatures may fall into the low to mid 30’s and rain continues. For now will keep everything liquid over SE TX, but should future model runs lower surface temperatures any more would need to think about some freezing rain potential in our NW counties Friday morning.

[Ntxw]

Some notable changes on the GFS at 5h particularly in the upper midwest. Thinking its going to be a cold run

[JayDT]

I could be way off, but to me the system seems stronger on this run so far than on the 0z.

[JayDT]

It already has precip breaking out from DFW to the west at 18z Wednseday