Another Arctic Attack looming?

[yoda]

The ETA was perfect on the how much Cold Air would be here, but did horrible with the precip.

The GFS did horrible on the Cold Air and perfect on the precip.

Now if somebody would have taken a consensus of those two models like that then everyone would just say that person wanted snow.

This winter will be like this, a ridge build in the East with a Pacific Trough then like that it will flip to a Rex Blocking in the West with a large Trough in the East.

All we need to do is get the PV timed right with that trough in the East and then we may need to watch out.

Right. But right now... that PV is way far away... and Mr. Ridge is coming to visit the East for the next week or two...

[wx247]

I wouldn't trust a model that far in advance.

That's what everybody was saying about the models 2 weeks ago when they showed the Artic airmass and the snow for TX, S-TX and S-LA. for last week.

Boy did those people eat a CROW sandwich on that call.

Remember what I said about the models, when people stop believeing in the models thats when they (the models) will prove you wrong.

Sometimes they get it right... sometimes they don't. I am all for using it as a discussion tool and as a possible scenario, but I am just pointing out that I don't trust models as a general rule that far in advance. Trends and consistency are very important.

[CaptinCrunch]

I wouldn't trust a model that far in advance.

That's what everybody was saying about the models 2 weeks ago when they showed the Artic airmass and the snow for TX, S-TX and S-LA. for last week.

Boy did those people eat a CROW sandwich on that call.

Remember what I said about the models, when people stop believeing in the models thats when they (the models) will prove you wrong.

Sometimes they get it right... sometimes they don't. I am all for using it as a discussion tool and as a possible scenario, but I am just pointing out that I don't trust models as a general rule that far in advance. Trends and consistency are very important.

Totally agree on using models as a discussion tool ONLY.

Trends and consistency are always the best tool to use when forecasting on LR outlooks.

The current trend right now is a very cold period followed by a warm period to be followed by another very cold period and so on, I really don't see any long term periods of either warmth or extreme cold spells, just 7 to 10 days of each flip-flopping back and forth for the rest of winter.
Timing and precip on these flip-flops is what we are all watching and betting on. When I did my Winter Outlook for North TX it was based intirely on the current trends at that time looking at 4 months down the road, and I have been very, very close on the month to month forecast as of Christmas. I'm no pro, but I'm no amatuer either.

[Kelarie]

What do you see for the Austin area in the coming couple of weeks?

[Steve]

I watched Bastardi's "Big Dog" and what he said was that the tracks of each storm system would be further south (sort of a repeat of the last pattern). He's trying to time them off of the SOI, but the ridge over coastal Alaska is reminiscent of the winter of 1950 (record highs in the state of LA) where it just stuck there. He said none of the models were really seeing the intrusion of bottled up Canadian or cross-polar flow, but he's got a hunch it will happen. He was also talking out beyond the > 250 hour time frame.

I think most of us agree that weather patterns tends to repeat seasonally, and if that is the case, the trof that made it down to east Texas might be a little further west next time we get the pattern repetition. Whether the weak El Nino influenced southern jet can get some energy in there or crank another West Gulf low remains to be seen. But his thing is that he's cautioning anyone who thinks the winter is over based on the progs for the next 7-10 days to think again.

Steve

[aggiecutter]

A 7-10 day cold spell in Texas is an extended cold spell in my book. On average, a cold spell normally last 3-4 days in Texas. I do agree that there will be one such extended cold spell in January( mid to late month)with snow and ice over much of the Northern half of the state. And, another around mid-February with a mild period in between.

[aggiecutter]

CPC is still bullish on the cold air for Texas in their 6-10 and 8-14 day progs. They are especially bullish on it being wet. We'll see what happens next week.


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

[wx247]

Yeah, I do think precip. trends are especially great across much of the nation over the next 4-10 days. It is a big question of where the cold air will lie.

[cctxhurricanewatcher]

This deserves a "Bears Watch."

I agree, extreme cold winter events in Texas (IE South Texas Snowstorm) usually call for an encore or two or three before the season is over. That was true in 1983 and past colder than average winter seasons. Not saying we will have another 4-12 inch snow in the Coastal Bend. But it would not surprise me if we have a bout or two of consecutive days with highs hovering right around 32 and lows in the low 20's.

Just a gut feeling.

[yoda]

CPC is still bullish on the cold air for Texas in their 6-10 and 8-14 day progs. They are especially bullish on it being wet. We'll see what happens next week.


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

CPC is so much based off GFS its not even funny.

[jeff]

I do not see any indication of an arctic outbreak during the first week of Jan. The upper level pattern is not really favorable for such, with ridging in the SE US and troughing in the west. A shallow air mass could drop down the front range, but I think it will be mixed out fairly quickly.

There will likely be intrusions into the N and C plains and Midwest as well as the New England, but not for the southern plains.

After about the 15th there are a few indications of colder conditions.

One thing is for sure, it is going to become increasingly wet across TX and LA over the next week as an active sub-tropical jet supplies several disturbances and Gulf moisture steadily increases on the back side of the SE US ridge. It will snow again in SE TX probably sooner than I think, but to get a foot that is not very likely.

I think some are thinking we may have another big snowstorm here in TX, but the fact is that the Dec 24/25th storm was extremely rare and historical. Such an event had not happened for over 100 years and could easily not happen again for 100 years. It was a once in a lifetime event and those that shared in the experienced should be considered extremely lucky. I have lived through 2 historical events in Houston, this snowstorm and the floods of TS Allison. You could be a forecaster for many years and never see either of these events in your CWA.

[sertorius]

Jeff:

Thanks for the discussion!! It does seem the central plains will return to at least "normal" conditions but the EURO is much less gung ho than the GFS for the Tuesday event next week. I liked your thoughts about a return to moisture-I have not seen a sprinkle in 3 weeks!!!

[jeff]

Jeff:

Thanks for the discussion!! It does seem the central plains will return to at least "normal" conditions but the EURO is much less gung ho than the GFS for the Tuesday event next week. I liked your thoughts about a return to moisture-I have not seen a sprinkle in 3 weeks!!!

The storm track should set up over the central plains out of the SW US into the Great Lakes. You should being seeing some moisture in all forms during the next week or so as lows form in the lee of the Rockies and head NE and ENE. Mild and wet ahead of the lows and cold with frozen precip. behind the lows. Shallow arctic air mass could produce an overrunning ice storm in the central plains over the next week or so.

[wxguy25]

Adding to that, there will be a ton of warm air and moisture transported out of the GOM ahead of developing systems over the plains. combine that w/ favorable dynamics and you have the setup for a MAJOR wintertime severe wx outbreak for the Gulf coast and lower MS valley.

[Wnghs2007]

Adding to that, there will be a ton of warm air and moisture transported out of the GOM ahead of developing systems over the plains. combine that w/ favorable dynamics and you have the setup for a MAJOR wintertime severe wx outbreak for the Gulf coast and lower MS valley.

SEVERE WX KC LIKE!!!!!!! But always dies out before it reaches georgia so why am i getting excited.

[aggiecutter]

I agree with WXGUY25. I think there will be Tornado and or Severe Thunderstorm Watches issued for parts of Texas before the next Winter Storm Watch is issued. I still dont see the logic behind the forcast of the local mets. in Ft.Worth for an arctic front next week. Nearly all the models are screaming blowtorch next week for Texas and the east.

[wxguy25]

Actually (IMO) the pattern for the first 20 days of JAN may be unfavorable for a major arctic outbreak.

Why?

Because in order to get a major arctic outbreak of historic proportions (as I have heard some here try to insinuate) you MUST have a strong PV (polar vortex). This feature will be either over Labrador, Greenland or the arctic for the abovementioned period.

Some of the MOST severe arctic outbreaks like DEC 1983, 1989 have all involved an anomalously strong and displaced polar vortex.

The other feature that you need to have is an amplified longwave pattern w/ rex blocking or PNA ridge along or just off the west coast, and a –NAO. Those two features contribute to the amplification of the longwave pattern over North America. In some of the cases…a retrograding block that moved into eastern Canada associated with an NAO that was negative—going positive --was the mechanism which forced the PV to dive southeastward and initiate the arctic outbreak.

Meridional flow associated with amplified longwave patterns anchored by blocking is CRITICAL.

We have the reverse of this pattern currently. The reason why the GFS shows these arctic outbreaks in the long range is due to it’s over amplification/cold bias. How it can pull off an historic arctic outbreak without a strong PV over SE Canada is beyond rationale comprehension. It’s like I said in my JAN outlook; “those forecasters who live by the GFS will die by it” or in our case BUST by it.

[Portastorm]

CPC is still bullish on the cold air for Texas in their 6-10 and 8-14 day progs. They are especially bullish on it being wet. We'll see what happens next week.


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

CPC is so much based off GFS its not even funny.

Not true for today's CPC forecast. Both the 6-10 day and 8-14 progs are based on a spread of ECMWF, GFS, and Canadian ensembles. Usually you are right, they seem to buy the GFS and its ensembles hook, line, and sinker. But today they did not.

The main question they pose is just how much Arctic air seeps southward as shallow Arctic airmasses traditionally pose problems for all medium range models.

Shallow Arctic airmasses and an active Southern jet usually mean stinky ice storms for us in Texas! I'd rather have snow or sleet personally.

[sertorius]

I'm really beginning to wonder about below freezing temps for my area early next week-it seems the 18z gfs is backing off earlier runs-shocker I know. The EURO and the 18z GFS could not be further from thier 850 temps for Tuesday-GFS has the 0 line just past me-The EURO has it way North-the EURO also holds back the low giving us precip for Monday/Tuesday-I'm beginning to wonder if we won't just have cold rain next Tuesday and have to wait till Wed. or Saturday of next week-it all depends on how far this shallow cold air mass goes-By saturday one should be able to watch temps. north of here and get an idea-the ETA does have the 0 line thru central Nebraska by Sunday-who knows-at least I will see some precip. We need it badly!!

[yoda]

CPC is still bullish on the cold air for Texas in their 6-10 and 8-14 day progs. They are especially bullish on it being wet. We'll see what happens next week.


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

CPC is so much based off GFS its not even funny.

Not true for today's CPC forecast. Both the 6-10 day and 8-14 progs are based on a spread of ECMWF, GFS, and Canadian ensembles. Usually you are right, they seem to buy the GFS and its ensembles hook, line, and sinker. But today they did not.

The main question they pose is just how much Arctic air seeps southward as shallow Arctic airmasses traditionally pose problems for all medium range models.

Shallow Arctic airmasses and an active Southern jet usually mean stinky ice storms for us in Texas! I'd rather have snow or sleet personally.

Usually they do. But sometimes they do not.