Texas Winter 2019-2020

[1900hurricane]

It's not instability overall that was an issue I think. 2000 J/kg of SB CAPE is plenty, especially given the shear present. It's almost like there was too much low level jet, as crazy as that sounds. And not from a shear perspective, but from a temperature advection perspective. Due to some combination of cloudy warm sector and top end warm air advection in the low level jet, low level lapse rates were poor and theta-e was very flat to even slightly increasing wrt height in the boundary layer. In an open warm sector that didn't appear to be mixing well, that doesn't bode well for surface convection. If the storms were elevated at the top of the theta-e max for the most part, they'd also have less shear to work with and straighter hodographs.

Is this correct? ¯\_(ツ)_/¯ Nailing down failure modes in severe weather situations is hard (05/20/2019 perhaps the most vibrant example), and all I can do is speculate based on what I see and have seen. I wish I could claim to know for sure, but the only thing I know for sure is that I sure as heck can't!

[1900hurricane]

Just out of curiosity, using the 06Z LCH sounding, I took out everything below the theta-e maximum, which in this case was at 920 mb. This also coincided with the bottom of the low level jet and the MU CAPE. If storms were indeed mostly elevated around this level, the hodograph goes from large and curving to mostly straight/fish-hook looking with very little helicity.

[Texas Snowman]

BREAKING NEWS! - South Texas Storms and my long-time cold-mongering other coworker in the cubicle next to me have been discussing the end of winter in Texas. I heard talk of no ice/snow events this winter. More later...

Well, I was in Indianapolis the last several days. Springlike there with rain while it turned wintry here. Didn’t get to see yesterday’s snow in Grayson County, but I saw the remnants in spun out cars coming home from the airport last night and snow in the eaves of local roofs on the way to church this morning.

As a cautionary piece of advice, for those of you who cling to model runs as the Gospel truth, I’m reminded of a statement back on Jan. 3. As yesterday proved, future forecast ideas aren’t always etched in stone.

Sometimes, that reinforced wall just doesn’t hold.

[DFW Stormwatcher]

I want all 280 to all know that even though some beautiful flakes flew, the vast majority of places didn’t even have grass turn white so I declare that this indeed was not the end of the great DFW snow drought (although it was a nice appetizer).

I have spoken

Snow was close enough to drive to Decatur with the fam and enjoy the 3 inches. So 30 minute drive to real snow counts for me:). I don’t think it counts for dfw though. I’m just lucky we live in Keller now.

[TheProfessor]

We know the GFS is right because it has snow show up right on my door step and then instantly goes poof lol(The column is quite dry for Louisiana actually, which is exactly what I need for my allergies.)

Where do you live?

I'm in SELA on the north shore.

[harp]

We know the GFS is right because it has snow show up right on my door step and then instantly goes poof lol(The column is quite dry for Louisiana actually, which is exactly what I need for my allergies.)

Where do you live?

I'm in SELA on the north shore.

Oh, ok!! I'm in Harahan!

[JMoses3419]

Regarding the failure mode on Friday:

My roommate (a degreed met) was out on this one and while I haven't heard his analysis directly, I do think the failure was related to the inability of storms to root to the surface where they could take advantage of the shear. Coincident to that, I think no single storm became dominant and because of that, while you COULD get something to happen in the ambient environment, there was no way to get the big event that was expected.

Up in this area (central Oklahoma) while there was morning convection, it was elevated = hail threat. CAA came in too fast and killed the threat here.

[harp]

This is so confusing. I hear one day: This is looking good. The next day: Nah, not so much. I read MJO looks like it's moving in the right direction. PNA may be going positive, etc. It's difficult to have any expectations when things seem to change from day to day. I'm sure winter weather lovers are just as frustrated as I am. Arrgghh!!!

[TheProfessor]

This is so confusing. I hear one day: This is looking good. The next day: Nah, not so much. I read MJO looks like it's moving in the right direction. PNA may be going positive, etc. It's difficult to have any expectations when things seem to change from day to day. I'm sure winter weather lovers are just as frustrated as I am. Arrgghh!!!

These are the dangers of model watching, this is why in the extended range one should be looking at the ensembles and teleconnections and not hour to hour model runs. The models will always change in the extended range, and they will drive you crazy if you let them. My advice is to sit back, look at the models for fun, and don't fret when they change drastically.

[harp]

This is so confusing. I hear one day: This is looking good. The next day: Nah, not so much. I read MJO looks like it's moving in the right direction. PNA may be going positive, etc. It's difficult to have any expectations when things seem to change from day to day. I'm sure winter weather lovers are just as frustrated as I am. Arrgghh!!!

These are the dangers of model watching, this is why in the extended range one should be looking at the ensembles and teleconnections and not hour to hour model runs. The models will always change in the extended range, and they will drive you crazy if you let them. My advice is to sit back, look at the models for fun, and don't fret when they change drastically.

I guess that's my point. The teleconnections, etc are starting to look better, but it does not show up in the operational model runs.

[Brent]

This is so confusing. I hear one day: This is looking good. The next day: Nah, not so much. I read MJO looks like it's moving in the right direction. PNA may be going positive, etc. It's difficult to have any expectations when things seem to change from day to day. I'm sure winter weather lovers are just as frustrated as I am. Arrgghh!!!

These are the dangers of model watching, this is why in the extended range one should be looking at the ensembles and teleconnections and not hour to hour model runs. The models will always change in the extended range, and they will drive you crazy if you let them. My advice is to sit back, look at the models for fun, and don't fret when they change drastically.

I guess that's my point. The teleconnections, etc are starting to look better, but it does not show up in the operational model runs.

the op runs change so much it'll drive you crazy(trust me, I've been there), that's why I always look at the ensembles whenever possible(especially with a wintry threat to see if its a supported idea or just a wild unrealistic thing) basically

[bubba hotep]

The 18z GFS does a perfect job of proving today's discussion

GFS



vs GEFS

[harp]

I hate to sound ignorant, but what am I looking at here? ^^^^^

[Cerlin]

I hate to sound ignorant, but what am I looking at here? ^^^^^

The top is the operational GFS model. This is typically the one you watch that has exact precipitations and all of that stuff (and available on all the free model viewers). The bottom is the GFS’s ensemble, which is the average of every GFS member that goes on during one run. The operational GFS is essentially just one of the members that goes into the ensemble. The operational GFS is fairly warmer than the ensemble GFS on that run, indicating that it is an outlier rather than the consensus.

[bubba hotep]

I hate to sound ignorant, but what am I looking at here? ^^^^^

The 18z operational GFS, in the longer range, is warm outlier when compared to the ensemble mean. The GFS has lows warmer than the mean high on some days.

[harp]

Got it! Thanks to you both for the explanation. I thought that's what it was, I just wanted to be sure.

[Brent]

I hate to sound ignorant, but what am I looking at here? ^^^^^

The 18z operational GFS, in the longer range, is warm outlier when compared to the ensemble mean. The GFS has lows warmer than the mean high on some days.

just to add to this but I can remember several times where even the night before the GFS was way too warm for the next morning.. short range not even close to long range

[northjaxpro]

These are the dangers of model watching, this is why in the extended range one should be looking at the ensembles and teleconnections and not hour to hour model runs. The models will always change in the extended range, and they will drive you crazy if you let them. My advice is to sit back, look at the models for fun, and don't fret when they change drastically.

I guess that's my point. The teleconnections, etc are starting to look better, but it does not show up in the operational model runs.

the op runs change so much it'll drive you crazy(trust me, I've been there), that's why I always look at the ensembles whenever possible(especially with a wintry threat to see if its a supported idea or just a wild unrealistic thing) basically

Always stick closely to the ensembles!!!!

[TropicalTundra]

TWC app seems keen on a good amount of rain this week and next week

[CaptinCrunch]

There was record warmth all the way up to Boston this past weekend. Boston set an all time record high of 74 for January, and there were 700 reports of severe weather across the southeast from Texas to the Carolinas.

This winter so far has been almost the complete opposite of what most winter outlooks predicted with a Cold west and NW, cold along the Canadian border, and warm south and SE.