Texas Winter 2011-2012...

[Ntxw]

Yuck the teleconnections don't look too pretty in the short term. Hopefully the SE ridge can pump copious rains for Texas. It would help and prevent any kind of insane blowtorch in this not so happy pattern winter wise. Still shots of cold just more transient in nature imo for about a week.

[orangeblood]

Yuck the teleconnections don't look too pretty in the short term. Hopefully the SE ridge can pump copious rains for Texas. It would help and prevent any kind of insane blowtorch in this not so happy pattern winter wise. Still shots of cold just more transient in nature imo for about a week.

Not pretty!! It appears if there are any high pressure systems that move south they will be very modified cold air or have source regions in the Northern US Plains or Southern Canada. The extremely positive AO is killing any chance of Cold Arctic High pressures building in the Arctic or Siberian Highs from moving across to this side of the Hemisphere. Hopefully there's a Sudden Stratospheric Warming Event in the near future!!!!

[Texas Snowman]

Hmmm. Wonder where Larry Cosgrove is getting his idea about major cold next week. From a tweet earlier today:

http://www.examiner.com/weather-in-hous ... ber-8-2011

Specifically this comment: "Note that the GOES WEST image has two strong disturbances set to merge over the West, then moving through the Texas Panhandle (probably next Wednesday). I suspect locally heavy rain and strong thunderstorms will accompany the frontal structure of this feature as it moves through the Lone Star State. Afterward, very cold air and strong winds make a rousing return to Houston in late week."

[Ntxw]

Hmmm. Wonder where Larry Cosgrove is getting his idea about major cold next week. From a tweet earlier today:

Climo plays a role. Not that it won't get cold, there will be chilling fronts, just there is more zonal flow involved so anything that comes down will be modified and warm up after a day or two, nothing of deep freeze in nature. If one thinks about it, it's very el nino-ish no real cold just cloudy and wet weather induced chill.

Also there's probably going to be a big rainstorm next week. After the system passes by perhaps it might open doors to a more colder regime which might be what larry was talking about.

[gpsnowman]

How many days or weeks in advance can the AO be predicted to go positive or negative? And is it predicted to go negative soon? We need some cold and snow around here!

[orangeblood]

After looking at the NOAA global 30 h-Pa temperature monitoring feature, the PNA probably has the best chance to move in our favor over the next few weeks (to a more positive direction). There is quite a bit of warming going on at that level of the atmosphere in the North Central Pacific and usually translates into a downstream ridge a couple of weeks later. Now, my question would be if it does come to fruition, how cold will the air mass be once it taps into it ??

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org. For official information, please refer to NWS products.

[GRAYSONCO.WX]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
849 PM CST WED DEC 7 2011

.UPDATE...

UPDATED THE FORECAST TO INCREASE SKY COVER A BIT THROUGH THE
MORNING HRS. A RELATIVELY WEAK SHORTWAVE TROUGH WAS IN PLACE NEAR
THE AZ/NM/MEXICO BORDER AS OF 9 PM CST. THIS TROUGH WAS MOVING
EAST-NORTHEAST AND HAS CAUSED A DECK OF MID TO UPPER LEVEL CLOUDS
TO DEVELOP FROM CENTRAL NEW MEXICO INTO FAR WEST TX. THIS PLUME OF
CLOUDS WILL MOVE EAST OVERNIGHT OVER NORTH TX. THESE CLOUDS ARE
SCATTERED TO BROKEN IN NATURE AND ARE EXPECTED TO HAVE LITTLE
IMPACT ON OVERNIGHT LOWS...SO NO OTHER CHANGES WERE MADE TO THE
FORECAST FOR THE EVENING UPDATE.

Just saw this! Any chance we could see anything out of this, other than clouds?

[orangeblood]

How many days or weeks in advance can the AO be predicted to go positive or negative? And is it predicted to go negative soon? We need some cold and snow around here!

You don't necessarily need the AO negative to get cold/snow around here but it does increase your chances of getting sustained cold and much much colder temps. The predictions are probably only somewhat accurate out seven to ten days. Now the SSW event I was talking about earlier is usually a very good predicator to the ao turning negative a few weeks later.

[Portastorm]

FWIW, JB is tweeting this morning that the Canadian ensembles are showing a positive PNA around Christmas-time.

[orangeblood]

FWIW, JB is tweeting this morning that the Canadian ensembles are showing a positive PNA around Christmas-time.

Yeah, it appears the PNA is going in that direction. But where are the source regions? I think it's safe to say that Santa isn't bringing any down from his neighborhood any time soon. The GFS 6z run is a good example of not needing high latitude source regions to get it cold enough air around here for snow/ice. It shows a cold high pressure building on the Montana/Canada border late next week then moving directly down the spine of the Rockies with shortwave energy moving in from the southwest. Seems very plausible with the nights getting longer and snow building across the central plains!!!

[Portastorm]

Something else worth mentioning ... the Arctic Oscillation values continue at very high (positive) levels. One of the analog months/years which matches a weak-moderate Nina with very high AO levels was December 1989.

Do y'all remember what happened here in Texas during that time, especially close to Christmas?!

[gpsnowman]

Something else worth mentioning ... the Arctic Oscillation values continue at very high (positive) levels. One of the analog months/years which matches a weak-moderate Nina with very high AO levels was December 1989.

Do y'all remember what happened here in Texas during that time, especially close to Christmas?!

I do. I was in high school living in Highland Village (north of Dallas 30 miles)at the time and our swimming pool was frozen a foot thick. -1F was the low one night before Christmas. My brother and I decided to break up the ice in the pool and ended up cracking several tiles along the edge of the pool. My father was not pleased. By Christmas it had warmed up I believe. The local mets still talk about December 89 and of coarse it is mentioned on this forum quite a bit. It would be nice to have at least some cold around for Christmas.

[orangeblood]

Something else worth mentioning ... the Arctic Oscillation values continue at very high (positive) levels. One of the analog months/years which matches a weak-moderate Nina with very high AO levels was December 1989.

Do y'all remember what happened here in Texas during that time, especially close to Christmas?!

Good point Portastorm, I believe that was caused by what's referred to as a Cahiirs Connection which is the Alaska Ridge connecting with the Siberian Ridge over the Arctic Circle. It enables the polar jet to bring down cold Arctic high pressure systems into much lower latitudes from the Pole or even over from Siberia (Siberian Express??). It appears to form some sort of blockade from the US west coast all the way north of Alaska and prevents any Pacific systems from crashing into the lower 48 (all systems are forced up and over the top through the Arctic Circle). If someone else can bring any more insight into this weather phenomenon (is it even one?), I would greatly appreciate it.

[Ntxw]

Hmm could something be brewing cold wise for Christmas? One thing is for sure the Pacific has not been as bad as I would've thought going into the La Nina, and the coming break from Alaska/West coast ridging is probably a temporary relaxation period for it imo. There has yet to be a dominant GOA low, instead for the past month or so the -EPO has been king. Trends are always our friends.

[Tireman4]

In the Houston area ( I was a senior in high school at the time...Santa Fe), it got down to 11F and was downright chilly. Galveston Bay froze out at at least 8 feet and there was lake effect snow on Clear Lake ( near Johnson Space Center). Very interesting times.

[orangeblood]

12Z GFS Ensembles looking really interesting for next weekend, 17th-18th.

[Ntxw]

12Z GFS Ensembles looking really interesting for next weekend, 17th-18th.

Euro is latching onto it as well.




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Edit: Euro is showing potentially a +PNA/slight -AO/slight -NAO for christmas frame

[somethingfunny]

Something else worth mentioning ... the Arctic Oscillation values continue at very high (positive) levels. One of the analog months/years which matches a weak-moderate Nina with very high AO levels was December 1989.

Do y'all remember what happened here in Texas during that time, especially close to Christmas?!

Oh don't say that, I've finally been able to relax since I saw that snow earlier this week. Until then, I've been terrified that 2011 has *just one more* 100°+ day lurking in the extended range forecast. I just buried the summer for good and now we're talking sub-zero?

[Portastorm]

Hey look ... I just posted it as one of those weather items where you read it and think "hmmm ... that's kinda interesting." Who knows if it will verify. December 1989 was such an extreme event that the odds of anything like that happening this year are pretty slim. Most of us may never see anything like that in our lifetime.

Nevertheless, the analog connection makes me think the POTENTIAL is there for a major Arctic outbreak.

Meanwhile, as Ntxw and orangeblood have pointed out, next weekend looks interesting for us in the Southern Plains/Texas. Cold and stormy.

[Big O]

12Z GFS Ensembles looking really interesting for next weekend, 17th-18th.

Euro is latching onto it as well.




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Edit: Euro is showing potentially a +PNA/slight -AO/slight -NAO for christmas frame

Three things.

First, would someone post the 12z GFS ensembles, provide a link, and/or describe what they show.

Second, what exactly is the "Euro latching onto?"

Third, is the Euro showing +PNA, -AO, and -NAO in its teleconnection indices? Where can I see this?