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

[Tyler]

So now it's the 2nd half of Feb? I thought the timeframe was around the 2nd week in Feb?

The pattern change will occur the first few days of Feb, however, it will take a bit for everything to get right for the arctic air to flow down through Canada. As a huge PNA ridge takes place to the west, the cold air will have to flow around it then south through Canada. So, we won't feel the pattern change until a bit later on. I think its going to be cold around here in just weeks. So basically, everything is game on as it has been for the past couple of days.

[Tyler]

jschlitz, what did he say his point #5 was?

Basically he said the GFS and Euro operational runs right now are too unstable to trust and that the ensembles and the "trend" are better indicators of what lies ahead.

Ok, thank you! Luckily, the trend is being nice to us. Lets hope that continues.

[southerngale]

[img]http://www.11threcords.com/clients/Agency-X%20-%20Don't%20Hold%20Your%20Breath.jpg[/img]

[gboudx]

So now it's the 2nd half of Feb? I thought the timeframe was around the 2nd week in Feb?

The pattern change will occur the first few days of Feb, however, it will take a bit for everything to get right for the arctic air to flow down through Canada. As a huge PNA ridge takes place to the west, the cold air will have to flow around it then south through Canada. So, we won't feel the pattern change until a bit later on. I think its going to be cold around here in just weeks. So basically, everything is game on as it has been for the past couple of days.

Thanks Tyler. So maybe by the end of next week, the picture will come clearer. IMO, if there's no snow involved, I don't want any bitterly cold air. I've enjoyed the lower than expected gas and electric bills.

[millerblizzard1]

So now it's the 2nd half of Feb? I thought the timeframe was around the 2nd week in Feb?

The pattern change will occur the first few days of Feb, however, it will take a bit for everything to get right for the arctic air to flow down through Canada. As a huge PNA ridge takes place to the west, the cold air will have to flow around it then south through Canada. So, we won't feel the pattern change until a bit later on. I think its going to be cold around here in just weeks. So basically, everything is game on as it has been for the past couple of days.

Thanks Tyler. So maybe by the end of next week, the picture will come clearer. IMO, if there's no snow involved, I don't want any bitterly cold air. I've enjoyed the lower than expected gas and electric bills.

I agree. I like winter but if it waits until the later part of Feb I would rather bring on spring and gardening, fishing, camping etc.

[Extremeweatherguy]

I have a feeling that we will see more than one arctic surge during February. We may see one within the first 10 days, then see another 1-2 between the 10th and 20th and we will probably see one more between the 21st and 28th. I think the cold shot(s) during the first 10 days will be only capable of temps. 10-20 below normal MAX, but the ones between Feb. 10th and the end of the month may have more of a punch and could bring us into record cold territory (considering that Alaska is bone-chilling; record cold is not out of the realm of possibility). I think these ideas are similar to the same ideas that we have had over the last week or two and the time frame of the pattern change has not been moved much. To me it still looks like GAME ON!

[PTrackerLA]

Still waiting for the return of winter (been waiting since December actually ). The big problem I see is lack of snowpack in the midwest which will cause the temps to moderate quite a bit combined with the increasing sun strength/angle as it will likely be middle February before anything happens. I'm just hoping for one hard freeze this winter or the mosquitos will eat us alive this spring...better go stock up on the OFF now.... .

[Extremeweatherguy]

Still waiting for the return of winter (been waiting since December actually ). The big problem I see is lack of snowpack in the midwest which will cause the temps to moderate quite a bit combined with the increasing sun strength/angle as it will likely be middle February before anything happens. I'm just hoping for one hard freeze this winter or the mosquitos will eat us alive this spring...better go stock up on the OFF now.... .

The difference between this and a conventional arctic outbreak is that Alaska is seeing there coldest air in years right now, but with a typical outbreak thier air is much warmer. Even if there was to be no snowpack, this air would still cause the US to get quite frigid. If, however, a snowpack can build up, then this air could reach record breaking levels when it swept into the US.

[Portastorm]

SATURDAY MORNING UPDATE ... I see no reason to budge from my thinking. Major pattern change impacts Texas and southern Plains beyond Feb. 6. Arctic air intrusion and possible wintry weather episode around Feb. 10-11. Modeling and ensembles confirm.

The Arctic Express may not have left the station but passengers continue to board and it's leaving soon!

[Air Force Met]

SATURDAY MORNING UPDATE ... I see no reason to budge from my thinking. Major pattern change impacts Texas and southern Plains beyond Feb. 6. Arctic air intrusion and possible wintry weather episode around Feb. 10-11. Modeling and ensembles confirm.

The Arctic Express may not have left the station but passengers continue to board and it's leaving soon!

OK....I have a brief second to post before I'm off to do other thigns.

Yes...the passengers are still boarding. Now, we have the Canadian picking up on the pattern shift in the day-10 run...and closely matching what the GFS is putting out with a nice 1050mb high ready to slide down. The interesting thing to start watching once the low pressure moves from Alaska is if the pressures start to build...that is your true signs that Texas is getting an arctic outbreak.

Per the conversation earlier on, someone had said when the cold air is in Alaska it is Texas bound not bound really for the southeast. Someone had countered that Alaska was our source region, but that it didn't mean cold air in Alaska only had one outlet. The latter is a truer statement. Alaska is the cource region for our arctic outbreaks but there are numerous examples where extreme cold in Alaska gets pushed east with the trof and backdoors Texas with only cold weather but not anything earth-shattering.

What MUST happen in order for Arctic air to slide south, especially given the current setup of upper air with an active southern jet remaining strong (in otherwords...the trof is NEVER forecasted to become some monster dipping the jet all the way into central Mexico), is that the pressures with the associated bitterly cold air (and do NOT kid yourself some of you...this air is bitterly cold...and unusually cold even for Alaska...I discussed...as did others...a long time ago that the pattern in late January would be more conducive for bringing the Siberian Air into Alaska instead of Asia like it had been...and that is what is happening) ...anyway...the cold air msut also be associated with a strong high pressure system so the air is even more dense than normal. This way it slides southward an overwhelms the pattern. The Feb 1989 outbreak was a classic example of this.

So until we see that 1050+mb high ACTUALLY forming in the central Alaska/Yukon (arctic highs actually build some as they move southward so a 1050 there would be a 1060 in western Canada) and then when we see the ridge nosing up...that's when Texas will get arctic air. IF we see 1030 highs getting nosed out by the pattern, expect those highs and their cold air to more east into the eastern US.

Note: It is very difficult for the models to forecast the formation of these highs...they will pick up on some of it...but the intensities will be of a bit. By looking at the pattern now, we should start to see this in about 216-240 hours...5-7 Feb. Afterwards, the western ridge should start the train from Siberian and the air reinforced from there.

[WaitingForSiren]

I still dont see any major arctic outbreaks. I can see a strong cold front or two mid february, but overall I dont expect any arctic outbreaks rest of this winter. Besides, even IF there IS an arctic outbreak, it'll occur later in February, so the air wont be as cold as it could have been.

[Portastorm]

Air Force Met ... thanks for taking a few moments to post and elaborate on the upcoming pattern! I'll be watching for the development of that Alaskan high pressure ridge.

And thanks for educating us weenies, especially this particular weather weenie!

[Extremeweatherguy]

I still dont see any major arctic outbreaks. I can see a strong cold front or two mid february, but overall I dont expect any arctic outbreaks rest of this winter. Besides, even IF there IS an arctic outbreak, it'll occur later in February, so the air wont be as cold as it could have been.

that really made no sense though; the air in Alaska right now is much colder than their normal. So I do not see why -60F to -70F in January is any different than if it were to come down in mid February. I still think an arctic outbreak has real promise..especially since most of the ingredients are there for it.

[southerngale]

I still dont see any major arctic outbreaks. I can see a strong cold front or two mid february, but overall I dont expect any arctic outbreaks rest of this winter. Besides, even IF there IS an arctic outbreak, it'll occur later in February, so the air wont be as cold as it could have been.

that really made no sense. The air in Alaska right now is much colder than their normal. So I do not see why -60F to -70F in January is any different than if it were to come down in mid February. I still think an arctic outbreak has real promise..especially since most of the ingredients are there for it.

That's what I was thinking. What difference does it make if it's an Arctic front on January 28th or February 15th? I would imagine it depends on how cold the air is, not what the date is. You could be right about not getting the arctic outbreak, but as AFM pointed out, if things come together the right way, it's certainly more possible than it was a month ago.

AFM, thanks for posting. Hopefully you'll have time to pop in more often as we all look forward to your analysis. I've still got a few tickets left for the Arctic Express for anyone else who wants to jump on board.

[Air Force Met]

I still dont see any major arctic outbreaks. I can see a strong cold front or two mid february, but overall I dont expect any arctic outbreaks rest of this winter. Besides, even IF there IS an arctic outbreak, it'll occur later in February, so the air wont be as cold as it could have been.

OK...I'll ask...what are you seeing that will keep the arctic air from comig south or east (into the eastern US)? I ask because it's one thing to say you don't think so when you offer a reason but another when you disagree and offer no reasons. I also ask because all the models and the long range predictors are ALL coming into agreement that arctic air will be coming south or east (as yet undetermined) and now the Canadian is matching the pattern shift and backing the Aleutian low into Russia and ridging into AK/Western Canada.

So if all of that happens to some degree or another there WILL be an arctic outbreak. Now...the indicators can and might be wrong...and I am not saying 100% they are right...but what I want to know is what meteorologically do you see that disagrees with all the indicators? Is it scientific or a hunch...because if it's a hunch...well...we can leave it at that because there's no need even discussing unscientific hunches.

Also...define the difference b/w strong cold front and arctic outbreak. What would seperate the two in your mind and what locations?

Example: For NYC, A strong cold front means highs of ? and an arctic outbreak means highs of ? For Dallas A strong cold front means highs of ? and an arctic outbreak means highs of ? What about Atlanta?

So focus on those 3 places and what is the difference between a strong cold front and an arctic outbreak. Just curious so we have our definitions right.

[Tyler]

SATURDAY MORNING UPDATE ... I see no reason to budge from my thinking. Major pattern change impacts Texas and southern Plains beyond Feb. 6. Arctic air intrusion and possible wintry weather episode around Feb. 10-11. Modeling and ensembles confirm.

The Arctic Express may not have left the station but passengers continue to board and it's leaving soon!

OK....I have a brief second to post before I'm off to do other thigns.

Yes...the passengers are still boarding. Now, we have the Canadian picking up on the pattern shift in the day-10 run...and closely matching what the GFS is putting out with a nice 1050mb high ready to slide down. The interesting thing to start watching once the low pressure moves from Alaska is if the pressures start to build...that is your true signs that Texas is getting an arctic outbreak.

Per the conversation earlier on, someone had said when the cold air is in Alaska it is Texas bound not bound really for the southeast. Someone had countered that Alaska was our source region, but that it didn't mean cold air in Alaska only had one outlet. The latter is a truer statement. Alaska is the cource region for our arctic outbreaks but there are numerous examples where extreme cold in Alaska gets pushed east with the trof and backdoors Texas with only cold weather but not anything earth-shattering.

What MUST happen in order for Arctic air to slide south, especially given the current setup of upper air with an active southern jet remaining strong (in otherwords...the trof is NEVER forecasted to become some monster dipping the jet all the way into central Mexico), is that the pressures with the associated bitterly cold air (and do NOT kid yourself some of you...this air is bitterly cold...and unusually cold even for Alaska...I discussed...as did others...a long time ago that the pattern in late January would be more conducive for bringing the Siberian Air into Alaska instead of Asia like it had been...and that is what is happening) ...anyway...the cold air msut also be associated with a strong high pressure system so the air is even more dense than normal. This way it slides southward an overwhelms the pattern. The Feb 1989 outbreak was a classic example of this.

So until we see that 1050+mb high ACTUALLY forming in the central Alaska/Yukon (arctic highs actually build some as they move southward so a 1050 there would be a 1060 in western Canada) and then when we see the ridge nosing up...that's when Texas will get arctic air. IF we see 1030 highs getting nosed out by the pattern, expect those highs and their cold air to more east into the eastern US.

Note: It is very difficult for the models to forecast the formation of these highs...they will pick up on some of it...but the intensities will be of a bit. By looking at the pattern now, we should start to see this in about 216-240 hours...5-7 Feb. Afterwards, the western ridge should start the train from Siberian and the air reinforced from there.

Awesome analysis AFM. Have you seen the 12z ensembles, they look great! :

http://wwwt.emc.ncep.noaa.gov/gmb/ens/t ... 12812.html

[Tyler]

SATURDAY MORNING UPDATE ... I see no reason to budge from my thinking. Major pattern change impacts Texas and southern Plains beyond Feb. 6. Arctic air intrusion and possible wintry weather episode around Feb. 10-11. Modeling and ensembles confirm.

The Arctic Express may not have left the station but passengers continue to board and it's leaving soon!

OK....I have a brief second to post before I'm off to do other thigns.

Yes...the passengers are still boarding. Now, we have the Canadian picking up on the pattern shift in the day-10 run...and closely matching what the GFS is putting out with a nice 1050mb high ready to slide down. The interesting thing to start watching once the low pressure moves from Alaska is if the pressures start to build...that is your true signs that Texas is getting an arctic outbreak.

Per the conversation earlier on, someone had said when the cold air is in Alaska it is Texas bound not bound really for the southeast. Someone had countered that Alaska was our source region, but that it didn't mean cold air in Alaska only had one outlet. The latter is a truer statement. Alaska is the cource region for our arctic outbreaks but there are numerous examples where extreme cold in Alaska gets pushed east with the trof and backdoors Texas with only cold weather but not anything earth-shattering.

What MUST happen in order for Arctic air to slide south, especially given the current setup of upper air with an active southern jet remaining strong (in otherwords...the trof is NEVER forecasted to become some monster dipping the jet all the way into central Mexico), is that the pressures with the associated bitterly cold air (and do NOT kid yourself some of you...this air is bitterly cold...and unusually cold even for Alaska...I discussed...as did others...a long time ago that the pattern in late January would be more conducive for bringing the Siberian Air into Alaska instead of Asia like it had been...and that is what is happening) ...anyway...the cold air msut also be associated with a strong high pressure system so the air is even more dense than normal. This way it slides southward an overwhelms the pattern. The Feb 1989 outbreak was a classic example of this.

So until we see that 1050+mb high ACTUALLY forming in the central Alaska/Yukon (arctic highs actually build some as they move southward so a 1050 there would be a 1060 in western Canada) and then when we see the ridge nosing up...that's when Texas will get arctic air. IF we see 1030 highs getting nosed out by the pattern, expect those highs and their cold air to more east into the eastern US.

Note: It is very difficult for the models to forecast the formation of these highs...they will pick up on some of it...but the intensities will be of a bit. By looking at the pattern now, we should start to see this in about 216-240 hours...5-7 Feb. Afterwards, the western ridge should start the train from Siberian and the air reinforced from there.

Awesome analysis AFM. Have you seen the 12z ensembles, they look great! :

http://wwwt.emc.ncep.noaa.gov/gmb/ens/t ... 12812.html

[Portastorm]

SUN AM UPDATE:

For as great as the ensembles and some operational runs of the GFS looked yesterday ... today (sun), we have more variability. Sheesh!

GFS 0z run still says "here comes the cold around Feb. 9th and here, have some snow and ice, too."

GFS 6z run says: "No arctic cold or ice for you!"

Ensembles say: "Remember that cold I promised you yesterday? Forgeddaboudit."

Gggrrrrr ....

Guess we will need to watch and wait more before any exciting scenario looks more likely.

[jasons2k]

Did you expect something different?

[Extremeweatherguy]

SUN AM UPDATE:

For as great as the ensembles and some operational runs of the GFS looked yesterday ... today (sun), we have more variability. Sheesh!

GFS 0z run still says "here comes the cold around Feb. 9th and here, have some snow and ice, too."

GFS 6z run says: "No arctic cold or ice for you!"

Ensembles say: "Remember that cold I promised you yesterday? Forgeddaboudit."

Gggrrrrr ....

Guess we will need to watch and wait more before any exciting scenario looks more likely.

You can not only focus on models with this type of situation. Of course they will change back and forth from warm to cold, but the real thing to look at is the overall pattern. The pattern itself is trending toward a colder look, and the models will probably not all point towards cold until we are only a few days out. Don't worry...it still looks like we are on for the cold to start coming the week of the 5th.