Texas Winter 2018-2019

[Ntxw]

Ntxw, do you still believe that a big pattern change should develop by mid December or do you feel it will be later?

I've never thought mid December. Polar heights actually don't look great second half of December long range (though far far away) I think our best shot is early December.

[hamburgerman7070]

Ntxw, i just dont think things will come together by beginning of December imo. I will say that if we get a -epo, then all bets are off. It was prevalent in 13-14. Most niños dont get going until mid January for colder and stormier, so we will see if that happens again.

[Ralph's Weather]

Ntxw, i just dont think things will come together by beginning of December imo. I will say that if we get a -epo, then all bets are off. It was prevalent in 13-14. Most niños dont get going until mid January for colder and stormier, so we will see if that happens again.

Most cold El Ninos have to wait on a -AO to build which is a slow process. The very warm GoA that we have this winter drives the cold straight from Siberia into the US without having to wait on a PV disruption. This is abnormal for El Nino and makes this one of the very rare goldilocks winters where we have a strong STJ along with blocking from Alaska through Greenland (-EPO, -AO & -NAO). This is why I am predicting a 12" winter for areas north of I-20 with localized 20" amounts. There just is not any negative factors for our region. A consistent +PNA could be problematic I guess but I just don't see that happening and the STJ can still overcome that.

[hamburgerman7070]

Ntxw, i just dont think things will come together by beginning of December imo. I will say that if we get a -epo, then all bets are off. It was prevalent in 13-14. Most niños dont get going until mid January for colder and stormier, so we will see if that happens again.

Most cold El Ninos have to wait on a -AO to build which is a slow process. The very warm GoA that we have this winter drives the cold straight from Siberia into the US without having to wait on a PV disruption. This is abnormal for El Nino and makes this one of the very rare goldilocks winters where we have a strong STJ along with blocking from Alaska through Greenland (-EPO, -AO & -NAO). This is why I am predicting a 12" winter for areas north of I-20 with localized 20" amounts. There just is not any negative factors for our region. A consistent +PNA could be problematic I guess but I just don't see that happening and the STJ can still overcome that.

Ralph, maybe its the delayed but not denied situation. I still dont think we see a cold setuo evolve until mid december or later. Models arent latching onto it yet

[Ralph's Weather]

Ntxw, i just dont think things will come together by beginning of December imo. I will say that if we get a -epo, then all bets are off. It was prevalent in 13-14. Most niños dont get going until mid January for colder and stormier, so we will see if that happens again.

Most cold El Ninos have to wait on a -AO to build which is a slow process. The very warm GoA that we have this winter drives the cold straight from Siberia into the US without having to wait on a PV disruption. This is abnormal for El Nino and makes this one of the very rare goldilocks winters where we have a strong STJ along with blocking from Alaska through Greenland (-EPO, -AO & -NAO). This is why I am predicting a 12" winter for areas north of I-20 with localized 20" amounts. There just is not any negative factors for our region. A consistent +PNA could be problematic I guess but I just don't see that happening and the STJ can still overcome that.

Ralph, maybe its the delayed but not denied situation. I still dont think we see a cold setuo evolve until mid december or later. Models arent latching onto it yet

We are just now getting to the time.period where the models may begin to pick up hints up it. The expected pattern is still 10 days out at minimum. Patience is required as there will likely be multiple cold fronts in the mean time which will keep temps within striking distance before things line up with the STJ and a SW low.

[hamburgerman7070]

Most cold El Ninos have to wait on a -AO to build which is a slow process. The very warm GoA that we have this winter drives the cold straight from Siberia into the US without having to wait on a PV disruption. This is abnormal for El Nino and makes this one of the very rare goldilocks winters where we have a strong STJ along with blocking from Alaska through Greenland (-EPO, -AO & -NAO). This is why I am predicting a 12" winter for areas north of I-20 with localized 20" amounts. There just is not any negative factors for our region. A consistent +PNA could be problematic I guess but I just don't see that happening and the STJ can still overcome that.

Ralph, maybe its the delayed but not denied situation. I still dont think we see a cold setuo evolve until mid december or later. Models arent latching onto it yet

We are just now getting to the time.period where the models may begin to pick up hints up it. The expected pattern is still 10 days out at minimum. Patience is required as there will likely be multiple cold fronts in the mean time which will keep temps within striking distance before things line up with the STJ and a SW low.

Ralph, the cfs Dr. Cohen posted on his twitter page today reversed and now shows a blowtorch dec and especially January That will suck if that actually happens

[Portastorm]

I wouldn’t worry too much. The CFS has been garbage this fall. Bastardi over the last week on Twitter has shown multiple examples.

[hamburgerman7070]

:uarrow:

I wouldn’t worry too much. The CFS has been garbage this fall. Bastardi over the last week on Twitter has shown multiple examples.

Portastorm, is the cfs and cfs v2 the same? Always wanted to know that

[Portastorm]

:uarrow:

I wouldn’t worry too much. The CFS has been garbage this fall. Bastardi over the last week on Twitter has shown multiple examples.

Portastorm, is the cfs and cfs v2 the same? Always wanted to know that

Yes. Version 2 started in 2011. But for all intents and purposes it is the CFS.

[Ralph's Weather]

The ensembles are showing the -EPO/-PNA/=NAO pattern that can be great around here for early Dec. I still am targeting the 12/3-5 period for a possible Texas winter storm.

[Cpv17]

The ensembles are showing the -EPO/-PNA/=NAO pattern that can be great around here for early Dec. I still am targeting the 12/3-5 period for a possible Texas winter storm.

Could you or anyone else explain to me what these oscillations are and what regions they cover? I’m trying to learn more about all these different oscillations.

[Ptarmigan]

The ensembles are showing the -EPO/-PNA/=NAO pattern that can be great around here for early Dec. I still am targeting the 12/3-5 period for a possible Texas winter storm.

Could you or anyone else explain to me what these oscillations are and what regions they cover? I’m trying to learn more about all these different oscillations.

EPO
https://blog.weatherops.com/what-is-the ... scillation

EPO is East Pacific Oscillation. It is like North Pacific's version of North Atlantic Oscillation (NAO). Negative EPO has ridging over Alaska. Positive EPO has troughing over Alaska.

PNA
https://climate.ncsu.edu/climate/patterns/pna

The Pacific/North American Teleconnection Pattern (PNA) is a large pattern over North America. Positive PNA has ridging over the Western US and Canada, while there is troughing over the Eastern US. Negative PNA has troughing over the Western US and Canada, while there is ridging over the Eastern US.

NAO
https://climate.ncsu.edu/climate/patterns/nao

North Atlantic Oscillation (NAO) is often associated with Arctic Oscillation (AO). Negative NAO has ridging over Northeastern Canada and Greenland. Positive NAO has troughing over Northeastern Canada and Greenland.

[Ntxw]

The ensembles are showing the -EPO/-PNA/=NAO pattern that can be great around here for early Dec. I still am targeting the 12/3-5 period for a possible Texas winter storm.

Could you or anyone else explain to me what these oscillations are and what regions they cover? I’m trying to learn more about all these different oscillations.

Ptarmigan pretty much covered what they are, but I'd like to add a few notes. All being the different modes of ridge-trough pattern at 500mb where the jet stream is.

EPO - it is the cold/or warm loading pattern for North America as a whole. A negative (-)EPO is essentially a block over the northeast Pacific Ocean. What this does is directs Marine (warmer in winter) Pacific air up to the pole instead of North America and allows the continent to cool. The positive (+)EPO is the opposite and has a trough in the same region flooding North America with warmer marine air. You will hear the term (zonal flow) quite often and that's what it is. Nearly all severe Arctic outbreaks in Texas are associated with historic -EPO episodes.

NAO- It is the far North Atlantic from Eastern North America to Europe. There are two variants an east based NAO (Scandinavia) and west based NAO (eastern Canada-Greenland). When the NAO is negative the pattern over North America is blocked. This slows down the weather pattern over the continent and often you have bigger storms as they are not shredded in faster flow and can deepen. It also has a tendency to lock in place whatever air is present. The AO is often an extension of the NAO and both likes to follow one another. A huge part of the Arctic is made up of the North Atlantic Ocean.

PNA is the steering pattern of the US in general. It directs flow of cold air generated by the -EPO/-NAO/-AO. A +PNA means ridging over the western US at varying degrees, and a -PNA is the opposite with trough in the west and ridge in the east.

These are often the most talked about indexes along with AO which covers the Arctic. There is also the WPO (west Pacific Oscillation) that is the sister mode for west Pacific in East Asia (Siberia) adjacent to the EPO. A -WPO/-EPO is often the requirement for cross-polar flow from Siberia to the US.

[OKMet83]

Models hinting at winter mischief around the 6th and again around the middle of the month.. Nothing locked in but 06Z GFS shows light snow from far SW TX into NE portions of the state 5th into the 6th! I fully expect an active pattern of Snow/ICE coming down the pike as NW has been talking about..

[rwfromkansas]

PNA is the steering pattern of the US in general. It directs flow of cold air generated by the -EPO/-NAO/-AO. A +PNA means ridging over the western US at varying degrees, and a -PNA is the opposite with trough in the west and ridge in the east.

These are often the most talked about indexes along with AO which covers the Arctic. There is also the WPO (west Pacific Oscillation) that is the sister mode for west Pacific in East Asia (Siberia) adjacent to the EPO. A -WPO/-EPO is often the requirement for cross-polar flow from Siberia to the US.

This explains why people on most weather forums love the +PNA, since most boards are rather east coast focused. I never realized until becoming active on this forum again why TX prefers it neutral or negative. We obviously need a trough close enough so we can get the cold and wet weather, but not with the core of the cold to the east of us like a +PNA.

[Ntxw]

PNA is the steering pattern of the US in general. It directs flow of cold air generated by the -EPO/-NAO/-AO. A +PNA means ridging over the western US at varying degrees, and a -PNA is the opposite with trough in the west and ridge in the east.

These are often the most talked about indexes along with AO which covers the Arctic. There is also the WPO (west Pacific Oscillation) that is the sister mode for west Pacific in East Asia (Siberia) adjacent to the EPO. A -WPO/-EPO is often the requirement for cross-polar flow from Siberia to the US.

This explains why people on most weather forums love the +PNA, since most boards are rather east coast focused. I never realized until becoming active on this forum again why TX prefers it neutral or negative. We obviously need a trough close enough so we can get the cold and wet weather, but not with the core of the cold to the east of us like a +PNA.

+PNA and NAO are the love doves for everyone east of the MS. For them it always means cold, and snow, maybe nor'easters. A slightly -PNA is best since it means storms are digging down to our west. The -PNA does the same for us as the +PNA does for say Atlanta. We are also benefiting most when the PNA is transitioning from one extreme to another, diving from very positive to negative, or negative to positive. During a negative to positive move, the cutoff lows from our southwest is forced to kick out. During very positive to negative the ridge out west breaks down but keeping the cold air and a storm dives southwest.

[Snowflake7]

I am still learning all of the lingo here on Storm2K and if I am reading correctly we should see some activity 5/6 December?

[Brent]

Models hinting at winter mischief around the 6th and again around the middle of the month.. Nothing locked in but 06Z GFS shows light snow from far SW TX into NE portions of the state 5th into the 6th! I fully expect an active pattern of Snow/ICE coming down the pike as NW has been talking about..

it can't start soon enough

[Sambucol]

What temps can we expect in SETX with this next cold air intrusion next week?

[Cpv17]

What temps can we expect in SETX with this next cold air intrusion next week?

It’s too far out to tell for certain, but upper 20’s to low 30’s seem like a good bet for now.