Texas Winter 2012-2013

[HockeyTx82]

While what the models show is a very cold look, I'm seeing subtle signs that beyond the foreseeable period (back end orangeblood mentioned) the "pop" omega block may happen over Alaska due to the appearance of an emerging Aleutian low. While the 10th-15th certainly has the Arctic poised to drop look that cold isn't yet the extreme we're looking for, rather just the models trending colder and colder each run in the period before (remember this was supposed to be the warm up that's not likely to happen).

So what if any implications does that have on us in terms of cold, severity, longevity and it not happening at all? Perhaps I am just not reading into what you are saying and the answer is there.

[weatherdude1108]

:uarrow:

My Canadian friend, you misunderstand. When I wrote "severe weather," I meant like thunderstorms and tornadoes, and flooding rains ... not Arctic cold or snow or sleet. Next Tuesday we believe that a severe weather episode may impact the Austin area and other parts of Texas as a strong storm system rolls through the state.

I would never tempt Old Man Winter. Well, only on days that end in "y."

I just saw the recent discussion from ewx about next weeks event. May be interesting! But I'd rather not have tornadoes or hail if I can help it, especially now that I have a new weather station. Also interesting that last blurb of the low confidence in the forecast for late next week which is highly dependent on the track of the upper low in question.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE AUSTIN/SAN ANTONIO TX
335 PM CST FRI JAN 4 2013

.DISCUSSION...
THE LATEST RADAR DATA SHOWS LIGHT ECHOES ACROSS THE EDWARDS
PLATEAU...HILL COUNTRY AND INTO PORTIONS OF THE I-35 CORRIDOR. WE
COULD SEE THIS LIGHT PRECIPITATION CONTINUE THROUGH THIS EVENING
INTO TONIGHT AS AN UPPER LOW CURRENTLY OVER SOUTHERN NEW MEXICO
GRADUALLY LIFTS NORTHEAST. RAINFALL AMOUNTS WILL NOT BE OVERLY
IMPRESSIVE WITH AMOUNTS LIKELY REMAINING BELOW ONE TENTH OF AN INCH.
THICK CLOUD COVER WILL REMAIN INTACT ACROSS MOST OF THE REGION
TONIGHT. WE COULD SEE SOME CLEARING ACROSS THE EDWARDS PLATEAU AND
HILL COUNTRY LATE TONIGHT INTO SATURDAY MORNING AND THIS SHOULD
ALLOW TEMPERATURES TO DROP BELOW FREEZING. GIVEN THE EARLIER
PRECIPITATION AND VERY MOIST CONDITIONS IN THE BOUNDARY LAYER...WE
HAVE OPTED TO MENTION PATCHY FREEZING FOG ACROSS PORTIONS OF THE
EDWARD PLATEAU AND HILL COUNTRY. ELSEWHERE...WARM AIR ADVECTION...
CLOUD COVER AND LIGHT PRECIPITATION SHOULD KEEP OVERNIGHT LOWS ABOVE
FREEZING. THE PRECIPITATION SHOULD TAPER FROM WEST TO EAST TOMORROW
AND WE WILL CARRY A SLIGHT CHANCE OF RAIN FOR AREAS EAST OF I-35. A
DRY FORECAST IS IN STORE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT
WILL MOVE THROUGH BRINGING DRY AIR TO THE REGION. SOUTHERLY WINDS
QUICKLY RETURN TO THE AREA BY MONDAY AFTERNOON AS AN UPPER LOW
STRENGTHENS OVER THE DESERT SOUTHWEST/NORTHERN MEXICO. THE MEDIUM
RANGE MODELS CONTINUE TO SHOW DIFFERENCES WITH REGARDS TO THE TIMING
AND LOCATION OF THIS LOW AS IT MOVES INTO THE SOUTHERN U.S. PLAINS
EARLY NEXT WEEK. THE ECMWF MODEL HAS SHOWN BETTER CONSISTENCY WHEN
COMPARED TO THE GFS...SO WE HAVE OPTED TO FOLLOW IT/S SOLUTION. THIS
WILL BRING AN INCREASING CHANCE FOR SHOWERS AND THUNDERSTORMS TO
SOUTH CENTRAL TEXAS EARLY NEXT WEEK...ESPECIALLY ON TUESDAY. AS THE
PREVIOUS SHIFT MENTIONED...SOME STRONG TO SEVERE THUNDERSTORMS
REMAIN POSSIBLE WITH THIS UPPER SYSTEM. THE FORECAST INTO THE MIDDLE
AND LATTER PORTION OF THE UPCOMING WORK WEEK WILL BE HIGHLY
DEPENDENT ON THE PATH OF THE UPPER LOW AND OVERALL CONFIDENCE IN THE
DETAILS IS LOW AT THIS TIME. FOR NOW...WE WILL END PRECIPITATION
CHANCES WEDNESDAY NIGHT AND KEEP TEMPERATURES NEAR OR JUST ABOVE
CLIMATOLOGICAL NORMALS.

[Portastorm]

Pick your poison. The images below are from the Euro (top) and GFS (bottom) 12z ensembles at 240 hours.



Uploaded with ImageShack.us



Uploaded with ImageShack.us

[Ntxw]

So what if any implications does that have on us in terms of cold, severity, longevity and it not happening at all? Perhaps I am just not reading into what you are saying and the answer is there.

Major arctic attacks work in waves. Parts will come out slowly and you will get big storms blasting strong fronts getting it colder. That's what we are seeing on the models. Very cold arctic air. This is why in '85 Austin saw multiple snow threats, and in '89 before the plunge you had a series of ice/snow storms and hard freezes. At the end of the plunge the big Arctic high will come down and that's when the greatest chunk will plow through (beyond the forecast period). Feb 2011 came down in three waves, the Tuesday that iced up everything, the super-bowl snow on Friday, and then the plunge the following Tuesday again.

This is if the -EPO delivers, if not it will just be a series of arctic fronts lasting a few days

[iorange55]

I may be wrong (wouldn't be the first time) but while we usually do see the models advertise "extreme" cold almost every year. We usually don't have this much agreement in the models for this long of time. And usually we don't have the right kind of pattern for an outbreak, but it looks like things are different this time.

It's definitely interesting.

[weatherdude1108]

So what if any implications does that have on us in terms of cold, severity, longevity and it not happening at all? Perhaps I am just not reading into what you are saying and the answer is there.

Major arctic attacks work in waves. Parts will come out slowly and you will get big storms blasting strong fronts getting it colder. That's what we are seeing on the models. Very cold arctic air. This is why in '85 Austin saw multiple snow threats, and in '89 before the plunge you had a series of ice/snow storms and hard freezes. At the end of the plunge the big Arctic high will come down and that's when the greatest chunk will plow through (beyond the forecast period). Feb 2011 came down in three waves, the Tuesday that iced up everything, the super-bowl snow on Friday, and then the plunge the following Tuesday again.

This is if the -EPO delivers, if not it will just be a series of arctic fronts lasting a few days

The '85 reference reminds me of when I lived in San Antonio as a kid. San Antonio had a record snowfall officially at 13.5 inches. We had 14 inches in our backyard as measured with a yard stick. City was shut down and we were out of school for almost a week.

http://www.srh.noaa.gov/images/ewx/1985snowevent.pdf

[Ntxw]

Ok maybe this will help a little. The models are not (yet) showing extreme cold (for the conus)! The pattern is set up for delivery but what we are seeing from them is the step down process, trending colder for the period they say was supposed to be warmer as arctic air is working into the picture.

[funster]

Would really prefer some nice snow to this possible extreme cold outbreak. Broken pipes just make people sad and miserable, but big pretty snowflakes can make many people smile and create happy memories.

[Ntxw]

Also, I don't think 1985 is a good analog for the potential event. That was extreme NAO (564dm heights over Greenland) blocking which forced the cold into the eastern 1/3rd of the country. This will be NE Pac (564+ over Alaska) -EPO driven which is more in line of the 62, 83, 89, and 2011 drivers (not saying the cold will be the same)

[cycloneye]

From the Houston/Galveston afternoon discussion. Look what they say at the end and I highlighted.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
407 PM CST FRI JAN 4 2013

.DISCUSSION...
NOT TOO MANY CHANGES FOR THE SHORT TERM PART OF THE FCST WITH THIS
PACKAGE AS THE COLD/CLOUDY/WET PATTERN REMAINS IN PLACE OVER SE TX
THROUGH THE EARLY PART OF THIS WEEKEND. STRONG SOUTHERN STREAM JET
HELPING TO BRING A SERIES OF SHORTWAVES ACROSS THE REGION WITH THE
NEXT ONE LOOKING LIKE IT IS GOING TO MOVE THROUGH OUR CWA LATE TO-
NIGHT/SAT (PER LATEST THE WV LOOPS).

THE PERSISTENT BKN/OVC MID/HIGH CLOUD DECK SHOULD BREAK BY SUN AS
THE MAIN UPPER TROF AXIS SHIFTS EAST AND THE BRIEF RIDGING DEVEL-
OPS IN ITS WAKE. BUT AS IT HAS BEEN THE TREND OF LATE...THIS VERY
PROGRESSIVE UPPER PATTERN WILL BE BRINGING THE NEXT SYSTEM TOWARD
THE STATE QUICKLY. WHILE MODELS HAVE BEEN CONSISTENT WE ARE STILL
SEEING MARKED DIFFERENCES IN REGARD TO THE TIMING FOR THE PASSAGE
OF THE NEXT CLOSED UPPER LOW STORM SYSTEM. ECMWF RETAINING A LONE
WOLF ROLE WITH ITS SLOWER TIMING...WITH THE GFS APPEARING TO HAVE
SPED UP WITH THE 12Z RUNS. DID MAKE SOME CHANGES TO POPS FOR THIS
TUES/TUES NIGHT TIMEFRAME ACCOUNT FOR THE UNCERTAINTY. REGARDLESS
WE COULD BE DEALING WITH STRONG/SEVERE STORMS WITH THE PASSAGE OF
THIS SYSTEM (NO MATTER WHICH DAY IT ARRIVES). PROGS OF STRONG LOW
TO MID LEVEL INFLOW (40-50KTS)...FAVOURABLE POSITION OF THE UPPER
JET (LFQ) AND THE PASSAGE OF THE COLD FRONT ITSELF ALL SEEM TO BE
POINTING IN THAT DIRECTION. BEAR WATCH IN PLACE.

http://forecast.weather.gov/product.php ... glossary=1

[Ntxw]

Aren't Phases 5-7 not all that favorable for cold in the us though?
Or am I misinformed?

That is correct, it is not favorable. What came out of that post is you can see it has been weak and sparse most of the winter. Look at all the crazy lines, no defined wave near the dead circle. But now we have a vast area of convection in the Indian Ocean consolidating courtesy of a true MJO wave and ready to move. The models will pick up on the favorable phases as things get closer

Euro/JMA/Canadian all shifting towards it, 7/8/1 are central conus, 8/1/2 for the east

[Snowluvr]

If this arctic intrusion actually takes place, wouldn't areas along the gulf coast have the best chance at getting some precip? I remember in '89 I lived just north of Hattiesburg,Ms and areas around New Orleans and Slidell got some sleet and snow while we got nothing but extreme cold.

[SaskatchewanScreamer]

:uarrow:

My Canadian friend, you misunderstand. When I wrote "severe weather," I meant like thunderstorms and tornadoes, and flooding rains ... not Arctic cold or snow or sleet. Next Tuesday we believe that a severe weather episode may impact the Austin area and other parts of Texas as a strong storm system rolls through the state.

I would never tempt Old Man Winter. Well, only on days that end in "y."

I see Old Man Winter differently.....his icy touch, to me, is also the cause of tornadoes and severe weather (along with help from the jet stream and warm humid air).

No season is safe from him.

[Ntxw]

Brett Anderson of Accuwx posted his interpretation of the latest Euro weeklies and for the Rockies/Plains it is quite cold the rest of January though probably not to our surprise

http://www.accuweather.com/en/weather-b ... -1/3583265

[PTPatrick]

Watching intently here in Denver. Feb 2011 was bone chilling. High was -1 , and we had like 60 hours below zero. That was by far the coldest streak I've seen here yet, although I have seen it around 20 below here a couple times. 85, 89 and 83 were all cold here, feb 85 brought Colorado is coldest temp ever, -61 at Maybell. Not expecting that but you never know. It's tough to get below zero highs in Denver, happens but once or so a decade but often happens a couple days at a time. 115 hours below 0 here is the granddaddy record fom 1983.

[NDG]

So far what I am seeing from the models is for most of Country seeing a nice shot of Arctic air in the mid to late range, with the middle of the country seeing the coldest. I am not sure about being record breaking and or compare it to Jan 1985.
But one thing for sure, you guys in TX will continue with a cold pattern in place.

[orangeblood]

Also, I don't think 1985 is a good analog for the potential event. That was extreme NAO (564dm heights over Greenland) blocking which forced the cold into the eastern 1/3rd of the country. This will be NE Pac (564+ over Alaska) -EPO driven which is more in line of the 62, 83, 89, and 2011 drivers (not saying the cold will be the same)

Along with the X-Factor in this setup - the Major SSW occurring now, It's hard to ignore the similarities to 1985 though....just look at the 500 mb Northern Hemisphere pattern for January of 1985 to the GFS ensemble long range forecast in the 10-15 day range

[Ntxw]

Along with the X-Factor in this setup - the Major SSW occurring now, It's hard to ignore the similarities to 1985 though....just look at the 500 mb Northern Hemisphere pattern for January of 1985 to the GFS ensemble long range forecast in the 10-15 day range

I'm not certain on this but most of the major blasts probably happened the same way regarding SSW.

The thing about 1985 and what the models are forecasting has subtle differences which makes a big difference. 1985 was very +PNA/extreme -NAO induced. Noticed the insane anomalies over Greenland. This essentially glides the high pressure southeast and Texas got glancing blows. Core of the cold was over the Lakes and northeast/mid-atlantic.

The second anomaly map is -EPO dominated with the -PNA which will slide the high down the west and central conus much like the other -EPO dominated periods of 83 and 89. This is if forecasting holds. I haven't yet seen the 564+ dm's over Greenland to point towards 1985

I like to use this site for analog patterns

http://www.hpc.ncep.noaa.gov/ncepreanal/

[northjaxpro]

Along with the X-Factor in this setup - the Major SSW occurring now, It's hard to ignore the similarities to 1985 though....just look at the 500 mb Northern Hemisphere pattern for January of 1985 to the GFS ensemble long range forecast in the 10-15 day range

I'm not certain on this but most of the major blasts probably happened the same way regarding SSW.

The thing about 1985 and what the models are forecasting has subtle differences which makes a big difference. 1985 was very +PNA/extreme -NAO induced. Noticed the insane anomalies over Greenland. This essentially glides the high pressure southeast and Texas got glancing blows. Core of the cold was over the Lakes and northeast/mid-atlantic.

The second anomaly map is -EPO dominated with the -PNA which will slide the high down the west and central conus much like the other -EPO dominated periods of 83 and 89. This is if forecasting holds. I haven't yet seen the 564+ dm's over Greenland to point towards 1985

I like to use this site for analog patterns

http://www.hpc.ncep.noaa.gov/ncepreanal/

January '85 was a historic arctic outbreak all across the Eastern 1/3 of the USA. Here in Jacksonville, the all -time record low temperature of 7 degrees was recorded during that epic event.

The pattern coming up in the next week to 10 days looks very cold for much of the country, but I hope it doesn't come close to anything like we saw in 1985. However, I have to admit the models have pretty good consensus on this potential arctic intrusion into the lower 48 and they have trended colder compared to 36 hours ago. It will be interesting to monitor how this unfolds in the next few days.

[orangeblood]

Along with the X-Factor in this setup - the Major SSW occurring now, It's hard to ignore the similarities to 1985 though....just look at the 500 mb Northern Hemisphere pattern for January of 1985 to the GFS ensemble long range forecast in the 10-15 day range

I'm not certain on this but most of the major blasts probably happened the same way regarding SSW.

The thing about 1985 and what the models are forecasting has subtle differences which makes a big difference. 1985 was very +PNA/extreme -NAO induced. Noticed the insane anomalies over Greenland. This essentially glides the high pressure southeast and Texas got glancing blows. Core of the cold was over the Lakes and northeast/mid-atlantic.

The second anomaly map is -EPO dominated with the -PNA which will slide the high down the west and central conus much like the other -EPO dominated periods of 83 and 89. This is if forecasting holds. I haven't yet seen the 564+ dm's over Greenland to point towards 1985

I like to use this site for analog patterns

http://www.hpc.ncep.noaa.gov/ncepreanal/

I see your point and that slight difference in the ridge Axis over Alaska appears to make an even better setup for extreme cold for the southern plains. But if you look at the PNA/NAO values from January 1985, they are in the range of what the models are forecasting for the time period coming up...PNA to stay positive with the NAO tanking! What really stands out is the extreme AO values of early 1985 and not sure if it will get that low. Exciting pattern to say the least!!!