EURO falls in line

[southerngale]

You go to someone not on S2K and ask them what a GFS ensemble is, and they'd probably tell you it was part of the latest woman's clothing line at Neiman Marcus!

[cctxhurricanewatcher]

I know, it just that fantasy of a couple days off work.... But that is just what that is, a fantasy. Probably would be required to come in, even if we had a major ice storm.

Fantasy maybe, but it's a good one!

I would like to see some sleet or snow as well here in south central Texas. Freezing rain/drizzle stinks because when you lose your power, the attraction of the winter weather loses its appeal, at least to me. Thankfully our "storm" this week was minor and few lost power.

And worse, you might not be able to post your observations about the event on this board.

No kidding! What makes all of this so much fun is getting excited and anxious with fellow weather fanatics.

You go to someone not on S2K and ask them what a GFS ensemble is, and they'd probably tell you it was part of the latest woman's clothing line at Neiman Marcus!

And one those someones might be my wife.

[aggiecutter]

Here's today's discussion from the Climate Prediction Center. Looks cold and wintry, particularly for the plains and midwest.

PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD
300 PM EST FRI DEC 09 2005

6-10 DAY OUTLOOK VALID FOR DEC 15 - 19 2005 TODAYS NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT REGARDING THE MEAN 500-HPA LONGWAVE PATTERN ACROSS MUCH OF THE NORTHERN HEMISPHERE. BELOW NORMAL 500-HPA HEIGHTS ARE FORECAST AT THE MIDDLE LATITUDES WITH ABOVE NORMAL 500-HPA HEIGHTS LIMITED TO THE HIGH LATITUDES. A BROAD 500-HPA TROUGH PERSISTS ACROSS MUCH OF THE CONUS WITH AN AMPLIFIED 500-HPA RIDGE JUST OFF THE WEST COAST INTO EASTERN ALASKA. ONE NOTABLE CHANGE FROM THE PREVIOUS MODEL SOLUTIONS THIS WEEK IS THE 500-HPA HEIGHT ANOMALY FIELD FOR THE CONUS. 500-HPA HEIGHT ANOMALIES ARE NOW FORECAST TO BECOME MORE NEGATIVE IN THE WEST COMPARED TO THE EAST. THIS SIGNIFICANT CHANGE IN THE 500-HPA HEIGHT PATTERN FITS WELL WITH THE RECENT TREND TOWARDS A RETROGRADING PATTERN SUGGESTED BY THE MODEL GUIDANCE DURING THE PAST TWO DAYS. THE PAIR OF STABLE POSITIVE 500-HPA HEIGHT ANOMALIES WILL LIKELY REMAIN OVER THE NORTH ATLANTIC AND NORTHWEST CANADA. THE NAO IS FORECAST TO TREND TOWARDS NEUTRAL BY DAY 10 BUT THE AO INDEX IS FORECAST TO REMAIN NEGATIVE. THE GRADUAL CHANGE IN THE NAO INDEX SUGGESTS THAT THE EAST MAY EXPERIENCE MODERATING TEMPERATURES. THE PERSISTENTLY NEGATIVE AO INDEX FAVORS BELOW TEMPERATURES FOR THE PLAINS AND MIDWEST. LOWER 500-HPA HEIGHTS IN THE WEST SUGGEST THAT BELOW NORMAL TEMPERATURES SHOULD EXPAND INTO THE ROCKIES... GREAT BASIN... AND PACIFIC NORTHWEST. ABOVE NORMAL TEMPERATURES SHOULD PERSIST FOR ALASKA. DESPITE THE REASONABLY GOOD AGREEMENT AMONG THE MODEL GUIDANCE REGARDING THE LONGWAVE PATTERN... THE PRECIPITATION FORECAST WILL LIKELY BE DETERMINED BY THE INTERACTION BETWEEN SHORTWAVES IN THE NORTHERN AND SOUTHERN STREAMS. THE ENSEMBLE MEANS FROM THE GFS SUPERENSEMBLE AND ECMWF FORECAST FAST 500-HPA FLOW ACROSS THE CENTRAL PACIFIC... SUGGESTING THAT THE SOUTHERN STREAM ENTERING THE LOWER LATITUDES OF NORTH AMERICA SHOULD BE QUITE ACTIVE. FOR THE SECOND CONSECUTIVE DAY... PRECIPITATION TOOLS STRONGLY SUGGEST MUCH OF THE CONUS SHOULD EXPERIENCE ABOVE NORMAL PRECIPITATION. THEREFORE... THE POTENTIAL EXISTS FOR MULTIPLE WINTER WEATHER EVENTS DURING THE 6-10 DAY TIME PERIOD. THE GREATEST LIKELIHOOD OF ABOVE NORMAL PRECIPITATION IS EXPECTED FOR THE EAST AND GULF COASTS DUE TO AN ACTIVE STORM TRACK AND ACROSS THE CENTRAL HIGH PLAINS DUE TO UPSLOPE FLOW. BELOW NORMAL PRECIPITATION SHOULD EXTEND FROM THE PACIFIC NORTHWEST INTO THE NORTHERN ROCKIES AND PLAINS. ELSEWHERE... BELOW NORMAL HEIGHTS ARE FORECAST TO PERSIST FROM EAST ASIA INTO THE CENTRAL PACIFIC. IN ADDITION... ALL ENSEMBLE MEANS SHOW A 500-HPA TROUGH CENTERED ACROSS THE WESTERN ALEUTIANS AND A SHARP 500-HPA RIDGE OVER EASTERN ALASKA... FAVORING ABOVE NORMAL PRECIPITATION FOR THE ALEUTIANS AND SOUTHWEST ALASKA. TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 15 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 8...15 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY 8...40 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8...AND 30 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7. MODEL(S) OF THE DAY: GFS SUPERENSEMBLE MEAN FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS ABOVE AVERAGE...4 ON A SCALE OF 1 TO 5....DUE TO GOOD AGREEMENT AMONG ALL THE MODEL GUIDANCE AND GOOD CONTINUITY AMONG THE GFS MODEL SOLUTIONS. THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE CPC AUTO BLEND FORECAST...KLEIN SPECIFICATIONS FROM THE ECMWF AND GFS ENSEMBLE MEANS... KLEIN AND ANALOG SPECIFICATIONS TO THE OFFICIAL BLEND... AND THE CDC TEMPERATURE FORECAST. THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE NEURAL NET AND ANALOG SPECIFICATIONS FROM THE OFFICIAL BLEND... THE CPC AUTO BLEND FORECAST... CPC CALIBRATED PRECIPITATION FROM THE VARIOUS INDIVIDUAL MODEL RUNS... AND THE CDC PRECIPITATION FORECAST. 8-14 DAY OUTLOOK FOR DEC 17 - 23 2005: DURING THE WEEK 2 PERIOD... THE GFS ENSEMBLE MEAN 500-HPA SOLUTIONS ARE IN REASONABLE AGREEMENT... MAINTAINING A HIGHLY AMPLIFIED LONGWAVE PATTERN ACROSS NORTH AMERICA. A SHARP 500-HPA RIDGE REMAINS OVER WESTERN NORTH AMERICA WITH A FAIRLY DEEP EASTERN NORTH AMERICA TROUGH. BELOW NORMAL 500-HPA HEIGHT ANOMALIES ARE FORECAST FOR MUCH OF THE CONUS EXCLUDING THE PACIFIC NORTHWEST. THREE SIGNIFICANT 500-HPA HEIGHT ANOMALIES PERSIST INTO WEEK 2 ACROSS THE NORTHERN HEMISPHERE: POSITIVE ANOMALIES NEAR GREENLAND... POSITIVE ANOMALIES OVER WESTERN CANADA... AND HIGHLY NEGATIVE ANOMALIES OVER THE CENTRAL PACIFIC. THE NEGATIVE 500-HPA ANOMALIES OVER THE CENTRAL PACIFIC ARE FORECAST TO BECOME THE DOMINANT FEATURE AT THE MIDDLE LATITUDES OF THE NORTHERN HEMISPHERE. THE HIGH AMPLITUDE TROUGH CENTERED OVER EASTERN NORTH AMERICA AND POSITIVE 500-HPA HEIGHT ANOMALIES NEAR GREENLAND FAVORS BELOW NORMAL TEMPERATURES ACROSS THE EAST. 500-HPA HEIGHT RISES IN THE WEST COULD RESULT IN A RETURN OF ABOVE NORMAL TEMPERATURES TO PARTS OF THE WEST. THE SPLIT-FLOW PATTERN EVIDENT DURING THE 6-10 DAY PERIOD CONTINUES INTO WEEK 2. THE HIGHLY NEGATIVE 500-HPA ANOMALIES OVER THE CENTRAL PACIFIC SUGGESTS THAT THE SOUTHERN STREAM COULD REMAIN ACTIVE... PROLONGING THE PATTERN OF ABOVE NORMAL PRECIPITATION FOR THE GULF COAST AND EAST. FOR THE REMAINDER OF THE CONUS... BELOW NORMAL PRECIPITATION IS EXPECTED FOR THE INTERIOR PACIFIC NORTHWEST AND GREAT BASIN. ELSEWHERE... NEGATIVE 500-HPA HEIGHT ANOMALIES CENTERED SOUTH OF THE ALEUTIANS SHOULD LEAD TO ABOVE NORMAL PRECIPITATION FOR THE ALEUTIANS AND THE SOUTH COAST OF ALASKA. ABOVE NORMAL TEMPERATURES SHOULD PERSIST FOR ALASKA. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 20 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...30 PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...AND 50 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11. FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS ABOVE AVERAGE TODAY... 4 ON A SCALE OF 1 TO 5....DUE TO REASONABLE AGREEMENT AMONG THE MODEL GUIDANCE. THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOG SPECIFICATIONS TO THE BLENDED HEIGHT FIELD...KLEIN PROBABILITIES TO THE GFS SUPERENSEMBLE MEAN... THE CPC AUTO BLEND TEMPERATURE FORECAST... AND THE CDC TEMPERATURE FORECAST. THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE NEURAL NET AND ANALOG SPECIFICATIONS TO THE BLENDED HEIGHT FIELD...THE CPC AUTO BLEND PRECIPITATION FORECAST...CPC AND EMC CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS ENSEMBLES...AND THE CDC PRECIPITATION FORECAST. FORECASTER: B. PUGH

The link to their products:

http://www.cpc.ncep.noaa.gov/products/forecasts/

[gboudx]

Very interesting aggiecutter. Thanks for posting.

[cctxhurricanewatcher]

Above normal temps in Alaska look good for continued cold shots into the lower 48. We shall see where they go.

[aggiecutter]

12z EURO Day 7...the arctic air has it eyes on Texas...

http://vortex.plymouth.edu/ecmna.108.gif

[Brent]

I don't know... the GFS has a zonal flow at Christmas now. Ugh. Zonal equals dry and boring for all of us and near normal on the temperatures.

The next cold snap looked like on the 18z run it gets shunted eastward and never makes it to Texas or any of the Deep South.

[aggiecutter]

The cold air is coming. This is the classic setup to have extreme cold between the Rockies and the Appalachains. If you'll notice on the map, there is low pressure in the Alleutians. In response to that, there will be lower than normal heights in the central and southern plains. With blocking over the top, the higher pressure will tend to gravitate toward the lower than normal heights. That's how you get repetitive cold shots down into the plains. It should get cold, and the cold will probably be extreme. If you were going to draw a map for extreme cold in Texas, that is how you would draw it.

[WhiteShirt]

The cold air is coming. This is the classic setup to have extreme cold between the Rockies and the Appalachains. If you'll notice on the map, there is low pressure in the Alleutians. In response to that, there will be lower than normal heights in the central and southern plains. With blocking over the top, the higher pressure will tend to gravitate toward the lower than normal heights. That's how you get repetitive cold shots down into the plains. It should get cold, and the cold will probably be extreme. If you were going to draw a map for extreme cold in Texas, that is how you would draw it.

When is this cold air supposed to make it down to Texas? I'm in the Houston area. Does it look like it will make it this far? Thanks.

[aggiecutter]

The cold should start to enter Texas by next weekend. With reinforcing cold shots, each of which will be progressively colder, the next 10-15 days after that. Bastardi thinks the worse will be between the 20th and the 30th. He and one of the other mets. on Accuweather mentioned this afternoon that this is a similiar set-up to 83' and 89'. Time will tell whether it will be that extreme or not. Having said that, the players are definately on the field for that type of an event.

[Brent]

I was more convinced 24 hours ago... I'm waiting for the 0z GFS to finish, it's up to next Saturday and it goes zonal then. Arctic outbreak(for now) is looking unlikely...

Break out the shorts...

[Brent]

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _264.shtml

4 days before Christmas... Cold... but not for Texas.

[aggiecutter]

Don't pay any attention to the operational GFS. It'll make you bi-polar.

[Brent]

Don't pay any attention to the operational GFS. It'll make you bi-polar.

It's fun to look at though... and this is the THIRD straight run showing no big cold outbreak. I tend to give it more trust when it's consistent.

Let's just say I wouldn't be calling this a repeat of 1983 or 1989 now. Confidence isn't that high in either scenario.

[Burn1]

Yes 20 - 30th Cold Event for the East......Don't see it for Texas like this past shot...

[Portastorm]

I don't think the GFS and European could look any more different than they do this morning (Sat). GFS says zonal by next weekend, Euro says amplified pattern.

What in the world is the GFS picking up on to change its pattern flow so dramatically within the last 24 hrs?!?!

Sorry guys but I say the smart money is on the Euro given its performance as of late and historically during the winter months. The cold is coming, get ready!

[TS Zack]

GFS has had no consistency ever since the Winter began. Overall it shows a Cold Pattern just before Christmas. In the Medium-range it could make you laugh.

Right Now, the best models to look at are the EURO and CANADIAN. They have been consistent on bringing down some Cold Air next weekend.

[cctxhurricanewatcher]

I don't think the GFS and European could look any more different than they do this morning (Sat). GFS says zonal by next weekend, Euro says amplified pattern.

What in the world is the GFS picking up on to change its pattern flow so dramatically within the last 24 hrs?!?!

Sorry guys but I say the smart money is on the Euro given its performance as of late and historically during the winter months. The cold is coming, get ready!

Right on! Most of the overnight AFD's by the Texas NWS offices are discounting the GFS too compared to about a week ago when a few of them were buying the GFS output which told them it was going to be seasonable to slightly below normal these last few days. It usually takes them one good Arctic outbreak down here for them to discard the GFS output to soley base their forecasts on .

The GFS is just a horrible winter model.

[Brent]

Now the GFS is back to showing the Eastern U.S. in the deep freeze right before Christmas... and then a suspicious storm on Christmas Eve.

It doesn't look quite as cold for Texas though(still below normal)... the brunt of it is farther east.

[aggiecutter]

Here's the reason you don't pay much attention to the operational GFS.
6z run it blow torches the whole country

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _336.shtml

6 hours later, the 12z run, there is brutal cold and a southern plains snowstorm.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _336.shtml