Texas Winter 2021-2022

[Brent]

Really hoping we can get a proper snowstorm up here... I'm supposed to already have a few inches according to climo yesterday was hardly anything

[bubba hotep]

The 18z GFS is a major outlier when compared to the GEFS. The op gets widespread 1" QPF across the state but the GEFS keeps the 1" line offshore and has most areas below 0.25". At some point, the higher resolution of the op should start to weigh heavier than the ensemble. Is that under 120 hrs? Under 84 hrs?

Altho you dont need 1" QPF for good snow. It only takes 0.2 as long as ratios are decent. Hence why most members do show snow/ice

Typically, a good "rule of thumb" with snowfall ensembles is to ignore anything less than 1". The 18z GEFS for DFW has 4 members with 1" or more, so we are still talking less than 20%. The one thing of note b/w both the EPS and GEFS is that basically all members that produce precipitation have it as snow. So we are kind of talking two different things here - what is your ensemble forecast of actually seeing accumulating snow vs. if you see precipitation than it is likely going to be snow (based on the ensemble raw output and not getting into soundings at this point).

[txtwister78]

The 18z GFS is a major outlier when compared to the GEFS. The op gets widespread 1" QPF across the state but the GEFS keeps the 1" line offshore and has most areas below 0.25". At some point, the higher resolution of the op should start to weigh heavier than the ensemble. Is that under 120 hrs? Under 84 hrs?

Altho you dont need 1" QPF for good snow. It only takes 0.2 as long as ratios are decent. Hence why most members do show snow/ice

Typically, a good "rule of thumb" with snowfall ensembles is to ignore anything less than 1". The 18z GEFS for DFW has 4 members with 1" or more, so we are still talking less than 20%. The one thing of note b/w both the EPS and GEFS is that basically all members that produce precipitation have it as snow. So we are kind of talking two different things here - what is your ensemble forecast of actually seeing accumulating snow vs. if you see precipitation than it is likely going to be snow (based on the ensemble raw output and not getting into soundings at this point).

I think that's subjective though with respect to QPF output in the medium range. I think you look at trends more than anything as opposed to just one run (in either direction). I think your point becomes more valid when you get into the short range and precip amounts are still under that 1" output. I think at that point you can begin to rule out certain outcomes. Across Central & S Central TX for example we've seen a bit more QPF with each run and so we have more members showing" snow" as one might expect. I do agree when you get into specifics of soundings/temp profiles that can be a little misleading as you describe above (raw output).

[Iceresistance]

Well, it may get even harder to get cold air here, the MJO has become inactive. (As posted before)


https://s10.gifyu.com/images/OH-NO.gif

[Texas Snow]

And poof it’s gone again Saturday DFW.

Well tomorrow is another GFS run (or 4)

Edit: Maybe some chilly rain finally by next Monday night

[txtwister78]

GFS starting to slowly inch toward its ensemble. 0z operational colder and has a better 500mb "look" for Thursday into Friday across Central/S Central TX. My guess is this is starting to look more like a regional event with limited moisture but some winter precip. I don't see the "bigger" event for the weekend but still some time to watch.

[Haris]

0z GEFS have gotten even bolder for Friday across Texas.

I expect the operationals to follow suit over time although dependent on euro and what it does

[Texas Snow]

Steve McCauley is not a believer


Still no sign of any major winter storm anytime soon. And yes, once again, that crazy American Model is going for 8 inches of snow this weekend. Not gonna happen, though it does turn colder for the latter half of the week into the weekend if that helps winter weather fans. I think they may be tweaking its cloud physics or something. That model has been spitting out snowmageddons for the past couple of weeks now.

[orangeblood]

0z GEFS have gotten even bolder for Friday across Texas.

I expect the operationals to follow suit over time although dependent on euro and what it does

CMC Ensembles coming around now too, this one has the type of potential to turn into something fairly significant

[HockeyTx82]

As crazy and inconsistent as the weather models are are we sure the Cowboys don't use them for game planning?

[wxman57]

GFS and European overnight operational model runs have something to say about this week and next week. I'm just the messenger, and this is not necessarily my forecast (yet). They certainly are backing away from any winter weather event across all but west Texas:

http://wxman57.com/images/snownazi.jpg

[wxman57]

I can remember Christmas 2004 we got a foot of snow in Victoria tx because of a gulf low. Is this the same setup possibly

Similar setup with the Gulf lows that keep forming. What's missing is deep sub-freezing air this far south. With steady warming across Alaska and British Colombia (into western Alberta) over the next 10 days, snow for southeast Texas looks very unlikely. It's hard to get the cold air over Saskatchewan to move south into Texas with a mostly zonal flow pattern.

http://wxman57.com/images/coldair.JPG

[cstrunk]

I enjoyed the accumulating snow in Longview Saturday night! Was definitely fun as it was unexpected. Stuck to the grass until Sunday morning.

I'm going hunting this weekend so I'm hoping for good travel conditions across I-20 towards San Angelo.

[Rgv20]

0zECMWF showing some winter precipitation South Texas Friday Morning...Not buying it yet but fun to look at

[gboudx]

From jeff for you SETX folks. Only pasting his comment for later this week and weekend.

Thursday-weekend:

This portion of the forecast becomes tricky. Cold air will be firmly in place on Thursday at the surface and deepening throughout the day. At the same time a WSW upper level flow aloft over top of the cold air will help to bring upper level disturbances across TX which will cause lift within the post frontal air mass. The surface cold front stalls over the NW Gulf and a series of weak coastal lows will form along the front. These lows will have the potential to attempt to force moisture northward and back into the cold air mass and then interact with lift from passing disturbances aloft.

The global forecast models have been bouncing around with the idea for mixed precipitation for days now, but there has been little consistency in their solutions between the models and their various runs. The ensemble support sort of adds a bit more confidence, but also yields varying mixed signals. As always in this area it will be a battle between the incoming dry and cold air and the moisture. If the incoming air mass is too cold and dry there will be no precipitation and if the moisture is more plentiful it is likely the air mass will not be cold enough for any mixed precipitation.

Best chances for the cold and moisture to line up will be northwest of a line from Columbus to Brenham to Huntsville Thursday night into Friday morning and possibly again on Friday night into Saturday morning. Profiles would support more of a sleet/snow mixture in that area, but moisture is hard to find and anything that falls looks to be very light. SE of this line, it looks too warm for anything other than light rain at the moment.

For now with confidence on the low side…the forecast for late week should be monitored for changes as to if and where any mixed precipitation may fall.

[wxman57]

Latest GFS run has Houston temps in the low-mid 40s with the freezing level around 10,000 ft this Fri/Sat. Around midnight Friday night, there is a small dip in temps around 1500 ft up. It's possible there could be a very shallow layer near 32F up there (below the warm nose). Cannot rule out the formation of a sleet pellet, but with surface temps in the lower 40s this would amount to only a curiosity.

[rwfromkansas]

And this is why I don’t tell my wife or friends until two days before…

[bubba hotep]

0zECMWF showing some winter precipitation South Texas Friday Morning...Not buying it yet but fun to look at

https://i.imgur.com/0GKtI8T.png

Given the current pattern, it looks like the best chance of some winter wx this weekend is across S. Texas. I just don't see a big system spinning up that impacts a large portion of the state, like some of the earlier model runs.

[wxman57]

0zECMWF showing some winter precipitation South Texas Friday Morning...Not buying it yet but fun to look at

https://i.imgur.com/0GKtI8T.png

Generally, you can ignore such winter precip forecasts if the amount is less than an inch (any gray colors). GFS indicates surface temps in the 40s down there with the freezing level above 10,000 ft. No shallow sub-freezing layer at all, indicating cold rain.

[orangeblood]

0zECMWF showing some winter precipitation South Texas Friday Morning...Not buying it yet but fun to look at

https://i.imgur.com/0GKtI8T.png

Given the current pattern, it looks like the best chance of some winter wx this weekend is across S. Texas. I just don't see a big system spinning up that impacts a large portion of the state, like some of the earlier model runs.

There's still a chance with the 2nd piece of energy coming in this weekend...Operationals may be taking it too far west across So Cal, if it comes in further east we may have something (more widespread event across the state). With the trough Southeast of Hawaii, I don't buy systems digging that far west like the operationals are showing. Need it to come in further east and there may be enough cold air around to for frozen precip