Upcoming cold for the South (Models, Maps, Discussions)

[Tyler]

On days 7 and 8, a ridge starts building in the west, and that is before hour 180, and by days 9 and 10, the ridge is very strong in the west, with cold arctic air flowing into the US. Good signs people! The pattern change is now closer than its ever been!

http://www.nco.ncep.noaa.gov/pmb/nwprod ... /fpc.shtml

But what about the GFS losing it as jkt21787 just posted?

I'm sorry, I don't understand your question. Are you talking about the winter storm? It doesn't have that big of a severe weather outbreak/winter storm as the 18z did, but the MAJOR pattern change is there, with sign of it on DAY 7!

[southerngale]

On days 7 and 8, a ridge starts building in the west, and that is before hour 180, and by days 9 and 10, the ridge is very strong in the west, with cold arctic air flowing into the US. Good signs people! The pattern change is now closer than its ever been!

http://www.nco.ncep.noaa.gov/pmb/nwprod ... /fpc.shtml

But what about the GFS losing it as jkt21787 just posted?

I'm sorry, I don't understand your question. Are you talking about the winter storm? It doesn't have that big of a severe weather outbreak/winter storm as the 18z did, but the MAJOR pattern change is there, with sign of it on DAY 7!

I thought jkt posted that the GFS no longer shows the pattern change we've been talking about all this time. With the ECMWF on board as well as the GFS, it looked more possible. I was just wondering if you thought it was still closer than its ever been even with the GFS backing off.

[Tyler]

On days 7 and 8, a ridge starts building in the west, and that is before hour 180, and by days 9 and 10, the ridge is very strong in the west, with cold arctic air flowing into the US. Good signs people! The pattern change is now closer than its ever been!

http://www.nco.ncep.noaa.gov/pmb/nwprod ... /fpc.shtml

But what about the GFS losing it as jkt21787 just posted?

I'm sorry, I don't understand your question. Are you talking about the winter storm? It doesn't have that big of a severe weather outbreak/winter storm as the 18z did, but the MAJOR pattern change is there, with sign of it on DAY 7!

I thought jkt posted that the GFS no longer shows the pattern change we've been talking about all this time. With the ECMWF on board as well as the GFS, it looked more possible. I was just wondering if you thought it was still closer than its ever been even with the GFS backing off.

The GFS hasn't backed off. I think what jkt was reffering to was the severe weather episode the 18z was showing for the south this weekend. Actually, the pattern change is much more encouraging on the 0z now than it was on the 18z. Especially since the ridging is building on day 7!

IMO, winter returns for the lower 48 after the Super Bowl.

Just checked the 0z Euro, and it looks nice as well.

[Tyler]

Ok, here is my current thinking:

If the 0z GFS is right, we'd be in for a doozy of an arctic blast. However, thats WAY into the future, and into lala land, so lets focus on the day 7-10 range, and look at the overall pattern.

This is 0z GFS hour 162:
http://www.nco.ncep.noaa.gov/pmb/nwprod ... _162.shtml

As you can see, west coast ridging is already evident, as a Low pressure system barrels into Alaska, and helps the polar vortex out of Alaska, which will also helps in relaxing the pacific jet.

174:
http://www.nco.ncep.noaa.gov/pmb/nwprod ... _174.shtml

You can really see a +PNA ridge in the west trying to build now. The polar vortex is moving farther away from Alaska, and the pacific jet appears to be FINALLY calming its darn self down.

192:
http://www.nco.ncep.noaa.gov/pmb/nwprod ... _192.shtml

A sustained +PNA ridge looks to be finally in place, with a trough swinging down into the east coast, bringing with it cold arctic air, that will finally flow into the US. Winter returns!

Skip head to day 10, 240 hr:
http://www.nco.ncep.noaa.gov/pmb/nwprod ... _240.shtml

A very nice +PNA ridge is shown here. While its cool in Texas, the majority of the cold air may be over the Northeast, as the trough looks to be confined over there. However, we have a nice block near Greenland, as you can see with that high pressure system, and we have an 1040MB high over Alaska, that may help dive bitterly cold air into the US (split flow). This is shown in GFS lala land hour 288:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _288.shtml

Then in GFS Dream land, it snows in Houston:
http://www.nco.ncep.noaa.gov/pmb/nwprod ... _336.shtml

The Euro also looks nice, with ridging looking to be taking place in the extended.

So this is what I believe, next weekend, we will see signs of ridging taking place on the west coast, as the pac jet will finally relax (probably for a 2 week period like we saw in December). The polar vortex will move away from Alaska, and that will also help in relaxing the pacific jet. There will be nice blocking near Greenland, that will help slow the flow across the US down, and allow a sustained trough over the eastern US. That trough will allow very COLD air to flow into the US. It remains to be seen if there will be a MAJOR arctic outbreak like the GFS is showing (and there very well could be), or who gets the coldest air. But one thing is for sure, a major pattern change will be taking place on Super Bowl weekend. And after the Super Bowl, we wait and watch to see where the bitterly cold air is headed...

I'm really liking how we can see evidence of a pattern change at day 7 now, within striking distance!
But this is just my opinion, .02 cents. It will be fun to see what happens, but IMO, winter will return for one last stand!

[southerngale]

On days 7 and 8, a ridge starts building in the west, and that is before hour 180, and by days 9 and 10, the ridge is very strong in the west, with cold arctic air flowing into the US. Good signs people! The pattern change is now closer than its ever been!

http://www.nco.ncep.noaa.gov/pmb/nwprod ... /fpc.shtml

But what about the GFS losing it as jkt21787 just posted?

I'm sorry, I don't understand your question. Are you talking about the winter storm? It doesn't have that big of a severe weather outbreak/winter storm as the 18z did, but the MAJOR pattern change is there, with sign of it on DAY 7!

I thought jkt posted that the GFS no longer shows the pattern change we've been talking about all this time. With the ECMWF on board as well as the GFS, it looked more possible. I was just wondering if you thought it was still closer than its ever been even with the GFS backing off.

The GFS hasn't backed off. I think what jkt was reffering to was the severe weather episode the 18z was showing for the south this weekend. Actually, the pattern change is much more encouraging on the 0z now than it was on the 18z. Especially since the ridging is building on day 7!

IMO, winter returns for the lower 48 after the Super Bowl.

Just checked the 0z Euro, and it looks nice as well.

Ok, that's good then. I'd like to see the cold (in hopes of some snow with it ). Since jkt posted it in this thread, I assumed he meant the GFS was backing off the cold pattern change.

I don't want to get my hopes up for nothing, but I can't help it when it starts showing a little consistency. Some are saying they see no change though. I don't check the models...I just rely on you guys and the mets when they post. I wish we had more mets posting in this forum though.

[southerngale]

The NWS will bust wildly all accross the south for the next weekend. NWS Houston has highs in the lows 70's and lows in the 50's. DON'T THINK SO!

They're already mentioning the possibility. A snippet from the overnight discussion...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
251 AM CST MON JAN 30 2006

TEMPS COULD END UP COOLER NEXT WEEKEND THAN THE CURRENT
FORECAST INDICATES IF THE LONGWAVE TROF ENDS UP DEEPER THAN THE
CURRENT GFS SOLN IS INDICATING. THE 12Z ECMWF IS MORE AGGRESSIVE
WITH THIS FEATURE, RIGHT NOW WILL STICK CLOSE TO THE GFS GUIDANCE
AS WARMER HAS BEEN THE WAY TO GO IN THE EXTENDED SINCE LATE DEC.

[Portastorm]

Props to Tyler ... nice analysis!

Props also to NWS Midland/Odesssa ... first NWS ofc in Tx to really mention the pending pattern change:

IT DOES APPEAR THAT WE WILL BE TRANSITIONING INTO A POSITIVE PNA
PATTERN NEXT WEEK AS THE FLOW OVER THE PACIFIC AMPLIFIES AND
ARCTIC RETROGRESSION OCCURS...EVENTUALLY PUTTING A POLAR VORTEX
OVER HUDSON BAY TOWARD THE END OF NEXT WEEK. THIS PATTERN CHANGE
TOWARD A AMPLIFIED AND BLOCKY REGIME HAS BEEN ADVERTISED BY THE
LONG RANGE MODELS FOR THE PAST SEVERAL DAYS...AND WOULD INDICATE
AN INCREASED CHANCE OF A SIGNIFICANT ARCTIC INTRUSION ACROSS THE
EASTERN TWO THIRDS OF THE CONUS. PRECIPITATION CHANCES INTO THE
WEEK 2 PERIOD WILL DEPEND ON THE AMOUNT OF ENERGY...IF ANY...THAT
CAN UNDERCUT THE WESTERN NOAM UPPER RIDGE. KEEP THE WINTER COATS
HANDY JUST IN CASE...

[Extremeweatherguy]

Finally they start to discuss it on the AFD's!!!

[Extremeweatherguy]

accuweather.com officially has a forecast of rain and ice for Spring, TX on February 12th! Lets hope this is a sign that we will get wintery weather during this cold period coming up! Also JB says that Feb. 5-15 will be the coldest temp. period for the country with this upcoming pattern, but he said that the 10-20 may be the coldest 11-day period in the nation over the last 6 years; if not beyond! He also said that the SW may get wet! Let's hope so...they need the rain/snow!

[WaitingForSiren]

Hint: you cannot believe anything Accuweather puts out =p

[Portastorm]

Hint: you cannot believe anything Accuweather puts out =p

We have literally plowed this ground before. These Accuweather forecasts are based on GFS runs only and are not a product of a human forecaster. They are computer generated numbers.

As for not believing anything they put out, I'm not in agreement. If they were not unreliable they wouldn't last long in the private sector. But they have been around awhile and that longevity is due to generally good forecasting, savvy marketing, and good business practices. Are they ever wrong? Of course they are! Tell me one forecaster or forecasting company that is right 100%?

JB this winter blew the January forecast badly and has progged several cold air invasions that never happened. But then again, show me someone who predicted that Jan. 06 would be one of the warmest Januarys in history? Back in November, JB warned of a very cold 2-3 weeks to start December and he was right. We shall see what happens in the days ahead and whether or not his bullish attitude about this pattern change occurs.

I have to say something because I grow weary of non-factual based comments about him that I see from time to time. I read him daily and know as well as anyone when he's on and when he's not.

But in the end ... for my money ... I'll take Air Force Met and Jeff and Don Sutherland any day of the week!

[cctxhurricanewatcher]

Props to Tyler ... nice analysis!

Props also to NWS Midland/Odesssa ... first NWS ofc in Tx to really mention the pending pattern change:

IT DOES APPEAR THAT WE WILL BE TRANSITIONING INTO A POSITIVE PNA
PATTERN NEXT WEEK AS THE FLOW OVER THE PACIFIC AMPLIFIES AND
ARCTIC RETROGRESSION OCCURS...EVENTUALLY PUTTING A POLAR VORTEX
OVER HUDSON BAY TOWARD THE END OF NEXT WEEK. THIS PATTERN CHANGE
TOWARD A AMPLIFIED AND BLOCKY REGIME HAS BEEN ADVERTISED BY THE
LONG RANGE MODELS FOR THE PAST SEVERAL DAYS...AND WOULD INDICATE
AN INCREASED CHANCE OF A SIGNIFICANT ARCTIC INTRUSION ACROSS THE
EASTERN TWO THIRDS OF THE CONUS. PRECIPITATION CHANCES INTO THE
WEEK 2 PERIOD WILL DEPEND ON THE AMOUNT OF ENERGY...IF ANY...THAT
CAN UNDERCUT THE WESTERN NOAM UPPER RIDGE. KEEP THE WINTER COATS
HANDY JUST IN CASE...

Correct me if I'm wrong. I think the Midland office has been the first offices in Texas in the past tp pick on the pattern changes and publically note them. The oldtimers in Brownsville (as you know Portastorm) would have been on this last week if they were still around. If the pattern continues to evolve towards the Arctic Express look, it will be fun to see the flip flopping in the coming days.

[WaitingForSiren]

I think accuweather has good forecasters, but their forecasts they PUT OUT are horrible. I prefer forecasts based on a human forecaster, not just some computer model.

[Portastorm]

Props to Tyler ... nice analysis!

Props also to NWS Midland/Odesssa ... first NWS ofc in Tx to really mention the pending pattern change:

IT DOES APPEAR THAT WE WILL BE TRANSITIONING INTO A POSITIVE PNA
PATTERN NEXT WEEK AS THE FLOW OVER THE PACIFIC AMPLIFIES AND
ARCTIC RETROGRESSION OCCURS...EVENTUALLY PUTTING A POLAR VORTEX
OVER HUDSON BAY TOWARD THE END OF NEXT WEEK. THIS PATTERN CHANGE
TOWARD A AMPLIFIED AND BLOCKY REGIME HAS BEEN ADVERTISED BY THE
LONG RANGE MODELS FOR THE PAST SEVERAL DAYS...AND WOULD INDICATE
AN INCREASED CHANCE OF A SIGNIFICANT ARCTIC INTRUSION ACROSS THE
EASTERN TWO THIRDS OF THE CONUS. PRECIPITATION CHANCES INTO THE
WEEK 2 PERIOD WILL DEPEND ON THE AMOUNT OF ENERGY...IF ANY...THAT
CAN UNDERCUT THE WESTERN NOAM UPPER RIDGE. KEEP THE WINTER COATS
HANDY JUST IN CASE...

Correct me if I'm wrong. I think the Midland office has been the first offices in Texas in the past tp pick on the pattern changes and publically note them. The oldtimers in Brownsville (as you know Portastorm) would have been on this last week if they were still around. If the pattern continues to evolve towards the Arctic Express look, it will be fun to see the flip flopping in the coming days.

You got it, CC! We've reminisced before about the ol' salts in Brownsville. I sure miss those guys.

Midland, Lubbock, Amarillo ... they're fairly good at mentioning all model spreads (not just the GFS) and warning of possible changes. Fort Worth isn't too shabby either once a pattern gets close to being locked in. My guess is that those offices that have more need/experience for wintry weather are better at it than the others. Theoretically, forecasting is forecasting, right? But ... the experience factor plays a big role like in any other job.

[Tyler]

Props to Tyler ... nice analysis!

Props also to NWS Midland/Odesssa ... first NWS ofc in Tx to really mention the pending pattern change:

IT DOES APPEAR THAT WE WILL BE TRANSITIONING INTO A POSITIVE PNA
PATTERN NEXT WEEK AS THE FLOW OVER THE PACIFIC AMPLIFIES AND
ARCTIC RETROGRESSION OCCURS...EVENTUALLY PUTTING A POLAR VORTEX
OVER HUDSON BAY TOWARD THE END OF NEXT WEEK. THIS PATTERN CHANGE
TOWARD A AMPLIFIED AND BLOCKY REGIME HAS BEEN ADVERTISED BY THE
LONG RANGE MODELS FOR THE PAST SEVERAL DAYS...AND WOULD INDICATE
AN INCREASED CHANCE OF A SIGNIFICANT ARCTIC INTRUSION ACROSS THE
EASTERN TWO THIRDS OF THE CONUS. PRECIPITATION CHANCES INTO THE
WEEK 2 PERIOD WILL DEPEND ON THE AMOUNT OF ENERGY...IF ANY...THAT
CAN UNDERCUT THE WESTERN NOAM UPPER RIDGE. KEEP THE WINTER COATS
HANDY JUST IN CASE...

Thanks Portastorm. Looks like NWS offices are starting to notice the pattern change. Awesome!

[gboudx]

DFW NWS doesn't even mention it this morning. I wish I could get excited about this like some of you guys, but I'm onto Lucy and her shenanigans. I'm approaching the football very carefully from now on. Like I said last week, maybe by mid-week I'll think about jumping on the bandwagon. I'm thinking I'll just wait until the day before. I really don't want to go flying into the air when the football is pulled. Besides, it's Spring according to my yard. Just about time to weed and mow.

[jasons2k]

The NWS DFW prob didn't mention it b/c any artctic intrusion is beyond 7 days...and trying to forecsast beyond that is futile...

[cctxhurricanewatcher]

The NWS DFW prob didn't mention it b/c any artctic intrusion is beyond 7 days...and trying to forecsast beyond that is futile...

For the record. Before the early December cold snap, NWS DFW was one of the last offices in the state to jump on board.

When NWS Houston/Galveston issues a "Bears Watch", katie the barn door cause it's coming.

[jeff]

One thing to keep in mind is that forecast beyond day 5 are not very accurate no matter who they come from. One can "see" an unfolding pattern and suggest what may or may not come 14 days out, but the small details (how much amplification, timing of a short waves, ect) can make hugh differences in the actual forecast numbers (highs, lows, and pop). This is the reason why most NWS offices do not dabble in the extended much, becuase there is honestly no skill in forecasting that far out. Granted, forecasters do and I am sure have closely examined the model output with its flip-flops and added experience into the mix and may be sitting their thinking my goodness look at this pattern, but do not say this publicly because they know better than to get excited about something 14 days off.

If some will remember, 2 weeks ago, today was the start of the arctic plunge and then it was the first week of Feb. and now it is around the 10th or 14th. Yes, there is cold air up there and the pattern looks increasingly favorable to bring it into the US, but to what degree, to where, how cold, any precip, ect just cannot be answered at this point in time. 2 weeks ago some on this board were predicting highs in the 30's and 40's for today and well we all see what it is and that is why trying to forecast specifics this far out is a mute point. The same thing happens in the summer time when a tropical disturbance emerges from Africa and is forecast by many to become the next Andrew and I suppose from now on the next Katrina.

[jasons2k]

One thing to keep in mind is that forecast beyond day 5 are not very accurate no matter who they come from. One can "see" an unfolding pattern and suggest what may or may not come 14 days out, but the small details (how much amplification, timing of a short waves, ect) can make hugh differences in the actual forecast numbers (highs, lows, and pop). This is the reason why most NWS offices do not dabble in the extended much, becuase there is honestly no skill in forecasting that far out. Granted, forecasters do and I am sure have closely examined the model output with its flip-flops and added experience into the mix and may be sitting their thinking my goodness look at this pattern, but do not say this publicly because they know better than to get excited about something 14 days off.

If some will remember, 2 weeks ago, today was the start of the arctic plunge and then it was the first week of Feb. and now it is around the 10th or 14th. Yes, there is cold air up there and the pattern looks increasingly favorable to bring it into the US, but to what degree, to where, how cold, any precip, ect just cannot be answered at this point in time. 2 weeks ago some on this board were predicting highs in the 30's and 40's for today and well we all see what it is and that is why trying to forecast specifics this far out is a mute point. The same thing happens in the summer time when a tropical disturbance emerges from Africa and is forecast by many to become the next Andrew and I suppose from now on the next Katrina.

Thank you Jeff!!!

Ditto...ditto...ditto, funny how some of us keep saying this and yet the same people say 'if you still don't believe it yet, it IS going to happen' as if they have a crystal ball or something. Oh well, as you pointed out with today's foracast example, the truth is always in the verifications