CAD storms thread.

[DaculaWeather]

Memphis AFD:

http://www.daculaweather.com/4_afd_meg.php

 

THE ECMWF AND GFS BOTH SHOW THE FIRST
WAVE OF PRECIPITATION THURSDAY INTO THURSDAY NIGHT AND AGAIN ON
FRIDAY. AS A RESULT CONFIDENCE IS ABOVE AVERAGE. THE ECMWF HAS
ABOUT ONE HALF INCH OF QPF ACROSS MEMPHIS THAT WOULD BE FREEZING
RAIN AND SOME SLEET ON FRIDAY. MEANWHILE THE GFS 1.5 INCHES OF
LIQUID OVER A POTENTIALLY SUB FREEZING SURFACE. PRECIP WILL TAPER
OFF FRIDAY EVENING WITH PERHAPS SOME WINTER WEATHER MOVING INTO
NORTHEAST MISSISSIPPI BEFORE IT ENDS.

WENT MUCH COLDER THAN MEX GUIDANCE FRIDAY AND FRIDAY NIGHT.

HERE IS WHAT WE KNOW...THERE IS A VERY COLD AIRMASS HEADED OUR WAY
AND THERE IS A SIGNIFICANT AMOUNT OF PRECIP POSSIBLE THURSDAY NIGHT
INTO FRIDAY. AS A RESULT SOME AREAS OF THE MIDSOUTH ARE LIKELY TO
SEE A SIGNIFICANT AMOUNT OF WINTER WEATHER INCLUDING FREEZING
RAIN...SLEET AND PERHAPS A LITTLE SNOW TO WRAP IT UP.

[burgertime]

12z is interesting. CAD isn't as strong but there is a strong enough HP there. At 500 the energy is further south but it keeps it's Miller B'ish look. 

[Cold Rain]

Not surprised to see the GFS trend northward with the overall threat. That's a pretty stout SE ridge. And with no blocking to hold the confluence in place, it allows the high to migrate north and east. It looks like there is still a threat for some wintry weather, but it doesn't have the look of a major winter storm for most of the SE.

We don't want to see a big system run toward the Lakes and reform off the VA coast. We'd want that to happen farther south.

You can make a legitimate case that the model is underdoing the CAD. But you can also make a legitimate case that the model is correct in sending a low toward the Lakes, given the orientation/strength of the SE ridge and lack of blocking.

The solution will change several more times, so grab some popcorn.

[dsaur]

Well, my 30% chance gave me .11 in a pretty good shower a while ago...so it begins. I've already beaten Goofy's projections, with more coming, and  I have rain chances through out the week, and building percentage wise as we go....with a low in the 60's late week.  Hot then bang...into the pre freezer coolerizer with no 30's until after truncation.  All propitious signs....for somebody else   T

[packbacker]

Not surprised to see the GFS trend northward with the overall threat. That's a pretty stout SE ridge. And with no blocking to hold the confluence in place, it allows the high to migrate north and east. It looks like there is still a threat for some wintry weather, but it doesn't have the look of a major winter storm for most of the SE.

We don't want to see a big system run toward the Lakes and reform off the VA coast. We'd want that to happen farther south.

You can make a legitimate case that the model is underdoing the CAD. But you can also make a legitimate case that the model is correct in sending a low toward the Lakes, given the orientation/strength of the SE ridge and lack of blocking.

The solution will change several more times, so grab some popcorn.

Agreed, atleast this threat will be a quick death instead of a nail biter. It will be a winter storm for somebody, just not us, maybe mtns start as ice but flip.

[Lookout]

Memphis AFD:

http://www.daculaweather.com/4_afd_meg.php

 

THE ECMWF AND GFS BOTH SHOW THE FIRST

WAVE OF PRECIPITATION THURSDAY INTO THURSDAY NIGHT AND AGAIN ON

FRIDAY. AS A RESULT CONFIDENCE IS ABOVE AVERAGE. THE ECMWF HAS

ABOUT ONE HALF INCH OF QPF ACROSS MEMPHIS THAT WOULD BE FREEZING

RAIN AND SOME SLEET ON FRIDAY. MEANWHILE THE GFS 1.5 INCHES OF

LIQUID OVER A POTENTIALLY SUB FREEZING SURFACE. PRECIP WILL TAPER

OFF FRIDAY EVENING WITH PERHAPS SOME WINTER WEATHER MOVING INTO

NORTHEAST MISSISSIPPI BEFORE IT ENDS.

WENT MUCH COLDER THAN MEX GUIDANCE FRIDAY AND FRIDAY NIGHT.

HERE IS WHAT WE KNOW...THERE IS A VERY COLD AIRMASS HEADED OUR WAY

AND THERE IS A SIGNIFICANT AMOUNT OF PRECIP POSSIBLE THURSDAY NIGHT

INTO FRIDAY. AS A RESULT SOME AREAS OF THE MIDSOUTH ARE LIKELY TO

SEE A SIGNIFICANT AMOUNT OF WINTER WEATHER INCLUDING FREEZING

RAIN...SLEET AND PERHAPS A LITTLE SNOW TO WRAP IT UP.

The amount of ice that the models are showing over Arkansas, western tn, and maybe extreme northern ms is just sick. Some places could get 2 to 3 inches of freezing rain..depending on the exact temps aloft which could cause it to mix with sleet. Either way, it reminds me of that huge icestorm they had a while back as far as totals go. And then they have another chance of a  pretty big ice storm just a few days later! They are really going to be blasted and it's going to be rough going out there, that's for sure.

 

Meanwhile, I don't see us getting anything in georgia. The high just simply is not in place soon enough to get the cold into ga and possibly sc either. NC is probably a different story...but the 12z gfs keeps there even above freezing.

 

It's hard to watch the models showing all this cold air and winter weather over such a huge portion of the country while there is virtually no chance at all to see anything here as it stands right now.

[NCCatawba]

As I sort of suspected with tnweathernut this morning, trending toward the BS/unsound/weird/no-Meteorological-sense euro model.

[griteater]

Not surprised to see the GFS trend northward with the overall threat. That's a pretty stout SE ridge. And with no blocking to hold the confluence in place, it allows the high to migrate north and east. It looks like there is still a threat for some wintry weather, but it doesn't have the look of a major winter storm for most of the SE.

We don't want to see a big system run toward the Lakes and reform off the VA coast. We'd want that to happen farther south.

You can make a legitimate case that the model is underdoing the CAD. But you can also make a legitimate case that the model is correct in sending a low toward the Lakes, given the orientation/strength of the SE ridge and lack of blocking.

The solution will change several more times, so grab some popcorn.

Good post, and sums up everything well.  It's a significant cold air damming setup, but the arctic air mass is having a tough time getting entrenched with the -PNA / SE ridging providing resistance.

[BullCityWx]

The Canadian is a big ole mess here with the 0z run. 20mm of sleet, 20mm of ZR.

[superjames1992]

Let's wait a few more model runs before we start slitting each other's wrists, okay? We are a week out. It could trend one way today and a whole different way tomorrow.

Even the 12z GFS still shows ISW criteria for many of the CAD-prone areas.

[NCCatawba]

Sure there is a big high present, but we need serious confluence or blocking to keep the 850's from surging.  I wouldn't be so quick to dismiss the Euro's depiction of a low from TN to the OH valley, which would harm even you guys chances of severe icing on the other side of the mountain.  I have seen low pressures track into big highs before.  I think that option is greater than anyone will give credit to at this point.  I think the GFS has been trending that way over the last couple of days.  Time will tell.

 

You are a wizard.

[Blue_Ridge_Escarpment]

Let's not forget one model run, whether good or bad, is not a trend toward another model.

[DixieBlizzard]

It's hard to watch the models showing all this cold air and winter weather over such a huge portion of the country while there is virtually no chance at all to see anything here as it stands right now.

 

Can this remark and it will be able to be used maybe 100x or so this winter. Such is life in GA!

[NCCatawba]

Let's not forget one model run, whether good or bad, is not a trend toward another model.

 

It's not just one model run if you read back. We alluded to the trend before the model even came out. You went from a snowstorm to ice storm to a euro storm over a period of several days. Trend.

[Blue_Ridge_Escarpment]

This is what I wanted to see. Great example of how powerful the euro is with CAD situations over the other models we are using. Notice the circle over the Hendersonville area (GSP prone area for ice that had a Winter Storm Watch several days ago). Anyway, as we can see the CAD has departed to the heavy CAD areas only by hr174. Good run by a good model. EURO to depict this best until the NAM and other short range models come into play.

 

 

0Z Euro, still showed a significant winter storm for CAD areas as you pointed out this morning

[DaculaWeather]

We're 7 days away... 

Here's the SE Region model verification scores for the past month for precip: http://www.daculaweather.com/4_hpc_verify_precip_month.php

and the past 3 months: http://www.daculaweather.com/4_hpc_verify_precip_3month.php

 

Much past 6 days and you might as well flip a coin...

http://www.daculaweather.com/4_model_verification.php

 

[Marion_NC_WX]

The thing we need to remember is that the GFS is not going to hone in on the actual strength of the CAD until we get inside of 4 days of the event.

 

Infact right now we are entering that "shadow" in the GFS (5-6 days out) where the model loses things only to bring it back with a  vengeance. Until we actually begin to lose our cold air source, high pressure and source of moisture (500mb flow), it's way too early to commit to any solution.

[BullCityWx]

12z Canadian has a really strong damming signal at 158.

[Lookout]

Let's wait a few more model runs before we start slitting each other's wrists, okay? We are a week out. It could trend one way today and a whole different way tomorrow.

Even the 12z GFS still shows ISW criteria for many of the CAD-prone areas.

Who is slitting their wrist? And as far as georgia goes, yeah it's quite a long ways out but there is good reason to be pessimistic because there is very good model support (especially for it being so far out)   for it being too warm in ga and sc (exception being last nights canadian).  And it's not just the fact they all agree, it's they all have been consistent for a while now. It would be one thing if there were some major differences between them and they were flopping around from run to run but that's not the case.

 

NC might be a different story though. It's a lot easier to get subfreezing temps there than sc and especially ga.

 

Can this remark and it will be able to be used maybe 100x or so this winter. Such is life in GA!

Yep...but i'm not just talking about winter storms..just the cold air. This arctic airmass pretty much takes hold of the entire country from coast to coast with the exception of  the deep south/southeast where the models have been amazingly consistent in showing it  staying the only warm spot thanks to a se  ridge from hell.  That sort of sucks.

[NCCatawba]

0Z Euro, still showed a significant winter storm for CAD areas as you pointed out this morning

 

It does. I want to see trends that help Charlotte and Raleigh. I may have been a little cliff jumpy there but time will tell according to the wizard. Something tells me there will be disappointment for those big cities.

 

Hope I am dead wrong and everything trends colder this week. 

[Snowless in Carrollton]

Who is slitting their wrist? And as far as georgia goes, there is very good model support (especially for it being so far out) for it being way too warm..and that is what all of them have consistently showed. NC might be a different story. It's a lot easier to get subfreezing temps there than sc and especially ga.

Yep...but i'm not just talking about winter storms..just the cold air. This arctic airmass pretty much takes hold of the entire country from coast to coast with the exception of the deep south/southeast where the models have been amazingly consistent in showing it staying the only warm spot thanks to a se ridge from hell. That sort of sucks.

how is Alabama looking in terms of wintry weather ?

[BullCityWx]

You never, ever, ever underestimate the SE Ridge .

[buckeyefan1]

You never, ever, ever underestimate the SE Ridge .

True  To be fair though, the death ridge has shown its ugly face several times on paper only for it to end up not as strong as expected.  Time will tell

[Cold Rain]

The Canadian blows. It triiiiies to go Miller B, but it just can't quite make itself do it. What happened to the nice little overrunning event. Now we have a storm...not what we wanted.

[Cold Rain]

Can't wait for the DT, "The GFs is asolute trex vrap" post.

[AirNelson39]

I personally agree with the decision to start the thread. We would have been having the same talks (multiple pages worth already) on a single system in the overall December discussion, which I believe December as a whole deserves to stay as the overall discussion. A system is going to move into the southeast next weekend, wintry or not, it's still a system that's worthy of tracking. Is it that hard for people to click the back button and view a system thread as well as a December thread?

There is no such thing as a jinx or superstition, your thoughts are what become things. If a model shows a potential system...let's talk about it, if it has the slightest chance of effecting ANYONE in the forum, let's start a topic on it.

[Shawn]

I don't see it getting this far south, but it's still a long way out

 

 

I agree. Just took a peek at the GGEM. Much different look on the precip type map at least, GFS both short and long range show nothing but rain through here.

[Lookout]

how is Alabama looking in terms of wintry weather ? As far as the cold air having trouble making it to GA, I guess those huge mountains to the northwest of GA will block the cold air ?

There's a chance the northern or northwestern part of the state gets some freezing rain around the 5 to 6 day time frame. Euro shows that happening for example. It will be interesting to see just how far south that the cold near the surface gets in alabama and ms.

 

As for here, I was referring mainly to cad. (this is where the cold comes in from the northeast). But yeah,  georgia  is screwed the vast majority of the time if the cold air is not already in place because of the mountains

[mackerel_sky]

We need to see if this is a hiccup or not. I think this whole run was crazy and like cr said, we don't need a gulf low if you want ice with this setup!

[Brick Tamland]

It does. I want to see trends that help Charlotte and Raleigh. I may have been a little cliff jumpy there but time will tell according to the wizard. Something tells me there will be disappointment for those big cities.

 

Hope I am dead wrong and everything trends colder this week. 

 

Well, that's what we have come to expect here the last two years.