Texas Winter 2013-2014

[amawea]

Quick update on the EPO tonight, models forecasting of it to go positive has not panned out. It rose to about -98 and is falling again. Still lurking up there, at the pace we are falling it may reach -2/-3SD's again. The WPO is also currently at it's lowest point so far this season.

This would lead to ridging in the west and troughing in the central or east wouldn't it? Plus cold air headed south east of the Rockies.
We got over 8 inches of snow here in north central Arkansas with the last round of cold(it's about all gone now). My daughter, son in law, and grandkids are coming from Houston for a few days right after Christmas. I sure wish we could get a little snow for them while they're here.

[dhweather]

Interesting from Ryan Maue twitter:

RAPv2 coming Jan 28, 2014 -- operational HRRR 3-km Q3-2014

NOAA PDF release: http://ruc.noaa.gov/pdf/NCEP_PSR_2013_RAP_FINAL_v5.pdf

[JonathanBelles]

If you look at the 2nd to last slide of that release there is an early hurricane season forecast track error verification. I have to wonder how much longer the GFS will be around. HWRF still needs massive upgrades.

[Ntxw]

Quick update on the EPO tonight, models forecasting of it to go positive has not panned out. It rose to about -98 and is falling again. Still lurking up there, at the pace we are falling it may reach -2/-3SD's again. The WPO is also currently at it's lowest point so far this season.

This would lead to ridging in the west and troughing in the central or east wouldn't it? Plus cold air headed south east of the Rockies.
We got over 8 inches of snow here in north central Arkansas with the last round of cold(it's about all gone now). My daughter, son in law, and grandkids are coming from Houston for a few days right after Christmas. I sure wish we could get a little snow for them while they're here.

It never technically left the ridging, it's been a relaxing period and was supposed to go positive according to guidance but that didn't happen. Snow is actually better during a -AO as a blocking pattern makes bigger storms with lower heights. Thus far the EPO has given us shallow cold air which has threatened ice more than snow.

[TeamPlayersBlue]

Care to explain to us students why? Is it due to the orgin of the air or the air pattern in the atmosphere etc? Thanks a bunch.


I am hoping that since the AO has remained positive for basically the whole beginning of winter, that it starts to go negative for the second half of winter. The NAO looks to be positive for the most part as well but -AO would bring more chilly air down for sure.

[TheProfessor]

Can there be an -AO and a -PO at the same time? If so what does that mean for Texas? Could it happen this winter? Or do they have to be opposite of each other ( one positive while the others negative)?

[Ntxw]

Care to explain to us students why? Is it due to the orgin of the air or the air pattern in the atmosphere etc? Thanks a bunch.


I am hoping that since the AO has remained positive for basically the whole beginning of winter, that it starts to go negative for the second half of winter. The NAO looks to be positive for the most part as well but -AO would bring more chilly air down for sure.

I don't fully understand why. But I do know a -AO means higher heights over the northern latitudes thus sending the lower heights to the mid-latitudes where we live. Lower heights generally means stormy weather and deeper cold air. For the most part the NAO and AO are connected, they tend to follow each other since the Atlantic Ocean and Arctic Ocean hooks up. The Pacific is kind of a loner with only the Bering as a slight connection to the Arctic Ocean.

October is a good indicator month for AO. This October it was very positive which likely will continue most of this winter. There's always breaks but predominantly it will not stay negative for long periods. For any sustained -AO it would likely require a significant stratospheric warming event which has yet to occur.

Can there be an -AO and a -PO at the same time? If so what does that mean for Texas? Could it happen this winter? Or do they have to be opposite of each other ( one positive while the others negative)?

There can be, 2009-2010 were mostly -EPO and -AO, it usually occurs during Nino's, specifically west based

[dhweather]

NTXW - I was trying to explain thickness to a coworker, and failed miserably. Do you have an easy way to explain it?

[Ntxw]

NTXW - I was trying to explain thickness to a coworker, and failed miserably. Do you have an easy way to explain it?

What kind of "thickness" are you looking at? Common rule is lower thickness is cold air advection, higher thickness is warm air advection.

Good link for it

http://www.theweatherprediction.com/habyhints/148/

[wxman57]

If you look at the 2nd to last slide of that release there is an early hurricane season forecast track error verification. I have to wonder how much longer the GFS will be around. HWRF still needs massive upgrades.

Or it makes you wonder how long the HWRF will be around. It's mostly a joke so far.

The trend on the snow line for this weekend is northward,not southward toward Texas. Nothing for Texas (Dallas-Ft. Worth at least) the rest of this month.

[Portastorm]

If you look at the 2nd to last slide of that release there is an early hurricane season forecast track error verification. I have to wonder how much longer the GFS will be around. HWRF still needs massive upgrades.

Or it makes you wonder how long the HWRF will be around. It's mostly a joke so far.

The trend on the snow line for this weekend is northward,not southward toward Texas. Nothing for Texas (Dallas-Ft. Worth at least) the rest of this month.

12z GFS op run says "not so fast, Heat Miser."

Winter storm lurks for North Texas late this month.



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[hriverajr]

12Z GFS does show a series of big strong Highs building in. I don't see the precip you are mentioning though Portastorm Also the brunt of the cold would be further east.

[ThunderSleetDreams]

12Z GFS does show a series of big strong Highs building in. I don't see the precip you are mentioning though Portastorm Also the brunt of the cold would be further east.

Umm... this shows a straight shot down the plains, not East.

[dhweather]

NTXW - I was trying to explain thickness to a coworker, and failed miserably. Do you have an easy way to explain it?

What kind of "thickness" are you looking at? Common rule is lower thickness is cold air advection, higher thickness is warm air advection.

Good link for it

http://www.theweatherprediction.com/habyhints/148/

I was trying to explain the infamous 540 line to him. Maybe this link will help me translate it to him - thanks!

[orangeblood]

Although still way beyond this models accuracy range, it has been trending towards MAJOR blocking over the Arctic circle starting around new years. Check out the incredible height rise over Alaska and into the Arctic towards the end of the 12z GFS run.

[Portastorm]

The 6z GFS ensemble mean shows a pretty good set-up for delivery of Canadian and/or Arctic air late in the month. We'll see.



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[hriverajr]

Those are anomalies. Actual 2m temps show brunt of cold air heading a bit farther east. Of course as usual models may not be handling low level cold air well. We will have to wait and see, and this is still in the future a bit. I am sure the 18z will probably show somewhat of a different solution.

[orangeblood]

12Z GFS does show a series of big strong Highs building in. I don't see the precip you are mentioning though Portastorm Also the brunt of the cold would be further east.

This is what Porta is mentioning with the storm early New Years week.....you can see the freezing line already through North Texas before the majority of the precip begins

[Portastorm]

Those are anomalies. Actual 2m temps show brunt of cold air heading a bit farther east. Of course as usual models may not be handling low level cold air well. We will have to wait and see, and this is still in the future a bit. I am sure the 18z will probably show somewhat of a different solution.

Well, yeah ... they are height anomalies. And that's my point ... they suggest sharp ridging off the West Coast of North America and fairly deep, lower heights in the central and eastern US. I'm not paying attention to the surface progs but the pattern and upper flow. When you have such a pattern as you know, it becomes a delivery vehicle for whatever air is up in the source regions. Like I said, it could be general Canadian air or if we get some blocking up there it could be Arctic air.

[TheProfessor]

What about the euro? Does it show potential winter weather for North Texas too?