Texas Winter 2019-2020

[TheProfessor]

That is about how I understand it too. A slower system in a blockier regime often features a more unidirectional wind field, a symptom of a more stacked system (less overall veering of winds with height). There's basically always some irregularity in the wind field in actuality, i.e. it's never a perfect and constant veering with height, but with a more unidirectional wind field, any irregularity gets magnified.

I'm not sure if this is the same resource TheProfessor is referring to, but here's a recorded presentation from AMS on backing aloft in a supercell environment.

How Much does “Backing Aloft” Actually Impact a Supercell?

Yep, that's the same guy who did the study.

[cheezyWXguy]

Thanks for the responses, Professor and 1900Hurricane. Reed seems like he's on board, but I've often heard that backing below 3km is much larger detriment than above it. With the backing occurring around 2km, I'm guessing this has a lot to do with why the initial supercells are expected to grow upscale so quickly.

[Brent]

In Lake Tahoe really just started snowing for real

[cheezyWXguy]

12z GFS shows a slightly more negatively tilted trough, and quite a bit less VBV than the NAM does.

[bubba hotep]

12z GFS shows 3 potential winter wx events for DFW over the next two weeks

[bubba hotep]

[Texas Snow]

https://pbs.twimg.com/media/EN2sK-cVUAACiao?format=jpg&name=small

Was just about to post this. As much as I want the actual snow, I actually more need the THREAT of snow. My kids have an ALL DAY swim meet Saturday and I would LOVE it to be cancelled. Mostly for me but they also both just had their wisdom teeth out so its not going to be their best effort anyway. Best to just call it off now I think

But yes, would love to see flakes flying no matter what.

[rwfromkansas]

At least some models are showing some hope. I am not going to get really interested until it's about 4 days away due to being burned so much. But, we need to start seeing chances to get a couple of busts to finally get one that happens.

[gboudx]

At least some models are showing some hope. I am not going to get really interested until it's about 4 days away due to being burned so much. But, we need to start seeing chances to get a couple of busts to finally get one that happens.

That's still too much time. Change to hours, or better yet, minutes.

[somethingfunny]

There's a lot of jittery nerves here in North Dallas and Richardson about tomorrow's storms. Reconstruction on my house from October's tornado probably won't be finished until August. The odds of one hitting me again are astronomical... Right?

[cheezyWXguy]

18z HRRR is noteworthy. Like on the 12z, initiation occurs west of DFW. Instability is approaching 2000j/kg and VBV is minimal.

[Haris]

[Haris]

Well that NAM certainly threw a wrench into the forecast.

[cheezyWXguy]

Well that NAM certainly threw a wrench into the forecast.

What do you mean?

[Cpv17]

Well that NAM certainly threw a wrench into the forecast.

What do you mean?

The latest run of the NAM has backed off quite a bit.

[cheezyWXguy]

Well that NAM certainly threw a wrench into the forecast.

What do you mean?

The latest run of the NAM has backed off quite a bit.

In terms of the precipitation depiction, I think it looks a little weird. For about 3 hours, it shows what appears to be initiation just west of dfw but doesnt really do anything, then a narrow line goes through. This doesnt really seem to jive with the conditions it shows in my opinion, because it actually shows more instability, higher SRH values, and less VBV than the 12z.

[starsfan65]

What do you mean?

The latest run of the NAM has backed off quite a bit.

In terms of the precipitation depiction, I think it looks a little weird. For about 3 hours, it shows what appears to be initiation just west of dfw but doesnt really do anything, then a narrow line goes through. This doesnt really seem to jive with the conditions it shows in my opinion, because it actually shows more instability, higher SRH values, and less VBV than the 12z.

I don't agree with this model run.

[bubba hotep]

What do you mean?

The latest run of the NAM has backed off quite a bit.

In terms of the precipitation depiction, I think it looks a little weird. For about 3 hours, it shows what appears to be initiation just west of dfw but doesnt really do anything, then a narrow line goes through. This doesnt really seem to jive with the conditions it shows in my opinion, because it actually shows more instability, higher SRH values, and less VBV than the 12z.

Looks like a stronger cap in place vs 12z, temps are a bit warmer between 850 - 700mb.

[newtotex]

The latest run of the NAM has backed off quite a bit.

In terms of the precipitation depiction, I think it looks a little weird. For about 3 hours, it shows what appears to be initiation just west of dfw but doesnt really do anything, then a narrow line goes through. This doesnt really seem to jive with the conditions it shows in my opinion, because it actually shows more instability, higher SRH values, and less VBV than the 12z.

Looks like a stronger cap in place vs 12z, temps are a bit warmer between 850 - 700mb.

Has initiation for the storms tomorrow moved further East or will the cap help to create more instability here in DFW proper?

[cheezyWXguy]

The latest run of the NAM has backed off quite a bit.

In terms of the precipitation depiction, I think it looks a little weird. For about 3 hours, it shows what appears to be initiation just west of dfw but doesnt really do anything, then a narrow line goes through. This doesnt really seem to jive with the conditions it shows in my opinion, because it actually shows more instability, higher SRH values, and less VBV than the 12z.

Looks like a stronger cap in place vs 12z, temps are a bit warmer between 850 - 700mb.

I dunno...capping looking pretty minimal in DFW between 22z and 0z, only about -15 j/kg CIN, which is about in line with previous runs. Temps dont look crazy different either, but it looks like 700mb level is more saturated.