Wintry Jan 15-16 Winter Storm Discussion & Obs

[griteater]

Yep, when it comes to snow east of the mountains, are hope is a big column cooling 850mb-700mb FGEN band which can allow heavy snow for some hours, this chance especially increases along the 85 corridor and NW in this deep cold CAD setup, there’s a big reason why CLT/GSO has a bigger snow average from Miller Bs vs Miller As

I'd say it matters how you classify them. I've come to classify Miller B as a low that tracks into E TN, then redevelops on the coast. Miller A/B hybrid as a low that tracks into SE Bama, then 'shuffles' to the east and up the coast. So, yeah, Miller A/B hybrid like late Jan 2010 can deliver more snow. That one was mostly snow here at LNorman. It was one of my favorites that wasn't all snow. I remember standing up on the earthen dam bank toward the end of the storm, and it was spitting sleet at 20 degrees with 15-20 mph winds

 

[NickyBGuarantee]

The mean is definitely east of the OP which would lean towards a flatter solution vs straight up the coast . Not that you don't already know that


Sent from my iPhone using Tapatalk

Implications for less warm nose for us?

 

[ATLwxfan]

EPS probabilities.
1 inch:View attachment 103891

3 inch:View attachment 103892

6 inch:View attachment 103894

12 inch:View attachment 103893

I’ve not seen such a widespread area of certainty for a 1 in snowfall for GA in a very long time if ever. Is that based on the predictive probability of the model X days out??


Sent from my iPhone using Tapatalk

 

[SD]

isn't that near the "benchmark" for the Carolinas as well?

It's better than the ops. Even on the next panel these aren't bad. Problem is there's a larger # west of the mean low which in my experience means we likely see the mean inch west in future runs as the eastward outliers come west

 

[Jrips2710]

If we don't break this streak this weekend, we suck...

 

[iGRXY]

I definitely fear the warm nose but I just really find it hard to believe that the LP is going to come THAT far north. This CAD is extremely strong. Way stronger than our usual CAD highs during winter storms.I want to wait until we are in the NAMs range before I can definitely say sleet and ZR are going to be a huge issue around the 85 corridor.

 

[LovingGulfLows]

You certainly can warm that much when you have 850s in the 40s over head. I'm not trying to be snotty, but it's called an Exothermic Process.

View attachment 103902


And at that exact same time frame, you've lost the press from the HP up north and thus your cold air feed.

View attachment 103909

The end result is you release the heat that the water absorbed higher up, and release it into the low levels, and with no fresh air supply, you slowly warm.

Take a look at those 850 temps to the west of the 850mb low in GA in the first panel. I wonder if that's associated with a CCB snow band?

 

[SD]

I definitely fear the warm nose but I just really find it hard to believe that the LP is going to come THAT far north. This CAD is extremely strong. Way stronger than our usual CAD highs during winter storms.I want to wait until we are in the NAMs range before I can definitely say sleet and ZR are going to be a huge issue around the 85 corridor.

Sfc CAD and mid level warm noses are independent variables loosely speaking. If the 850 low is between CAE and GSP as seen here you are going to push the snow line way W/NW

 

[EmersonGA]

What do the temps look like in the days after the storm on the Euro?

 

[iGRXY]

Sfc CAD and mid level warm noses are independent variables loosely speaking. If the 850 low is between CAE and GSP as seen here you are going to push the snow line way W/NWView attachment 103914

Of Course but the orientation in which they come from would hopefully be further south.

 

[smast16]

The worst part is we just know these 850 temps are being undermodeled. Just wait till the Nam gets a hold of it.

 

[SD]

You certainly can warm that much when you have 850s in the 40s over head. I'm not trying to be snotty, but it's called an Exothermic Process.

View attachment 103902


And at that exact same time frame, you've lost the press from the HP up north and thus your cold air feed.

View attachment 103909

The end result is you release the heat that the water absorbed higher up, and release it into the low levels, and with no fresh air supply, you slowly warm.

Didn't see this post but it's spot on. This system is likely to be tilted severely NW as the sfc low encounters a residual sfc cold pool and stays east but the mid level features are likely to be west

 

[atlwx]

Kirk Mellish is... watching.

Weekend winter system is 4,000 miles away

It would be scientifically unsound to show any kind of snow/sleet/ICE/Rain map this far out, in another 48 hours forecasters should have a better idea and can issue some early guesstimates.

www.wsbradio.com

 

[SD]

I'm not trying to rain on parades here at all I'm just telling you guys from experience you can watch all of the CAD you want and all of the sfc low tracks you want but the mid level features are your primary ptype drivers. The better hope to lock in snow/ip longer is to have an initial surge of fgen WAA that rapidly cools the column and out performs model expectations which can hold off the ever lurking mixing line longer than expected so you can pile up snow but even then if the 850 low is too far NW you eventually lose

 

[KyloG]

So similar to 2014

 

[Downeastnc]

Though that was 995 and 997 notwhat they are

The ens give hope that the over amped op runs are just going to correct SE as we get closer to go time.....

Here are all the members locations. Kind of strangethe mean seems to be weighted a little E of the clustering View attachment 103900

This is encouraging for central and eastern NC......but the track also needs to be less up the coast and more ENE, all the models really drive the storm NNE right along or just inland and that's ?.....at least for the eastern half of NC....

 

[Tarheel1]

I'm not trying to rain on parades here at all I'm just telling you guys from experience you can watch all of the CAD you want and all of the sfc low tracks you want but the mid level features are your primary ptype drivers. The better hope to lock in snow/ip longer is to have an initial surge of fgen WAA that rapidly cools the column and out performs model expectations which can hold off the ever lurking mixing line longer than expected so you can pile up snow but even then if the 850 low is too far NW you eventually lose

It’s all about the 925 millibar level! Seen many a sleet and ZR storm with 2m temps in low to mid 20s and a pesky +1 or + 2 degrees at 925

 

[olhausen]

Yep Nashville was calling for 1-2 a couple days before last week’s storm. They gradually went up to 5-6 the morning of and 8 inches was common when it actually fell. They aren’t going to say omg 10-15 inches of snow will fall this weekend this far out.

Not saying it is and I hope all who haven’t got snow can score soon. That said the euro is right where I‘d want it at this point. This could end up over middle Tennessee if it trends northwest.

 

[Snowflowxxl]

All of the “snow” in atlanta is probably sleet

 

[LovingGulfLows]

I'm not trying to rain on parades here at all I'm just telling you guys from experience you can watch all of the CAD you want and all of the sfc low tracks you want but the mid level features are your primary ptype drivers. The better hope to lock in snow/ip longer is to have an initial surge of fgen WAA that rapidly cools the column and out performs model expectations which can hold off the ever lurking mixing line longer than expected so you can pile up snow but even then if the 850 low is too far NW you eventually lose

IMO, I can see an area of enhanced snowfall just north of the sfc wedge front boundary. The bitterly cold air from the wedge lifts the advancing warm moist air from the southwest. The Euro showed it centered over much of the ATL metro where we saw 1+ inch per hour rates at the start of the storm. That's where much of the snow could pile up for many places.

 

[Meteorologist1999]

It’s all about the 925 millibar level! Seen many a sleet and ZR storm with 2m temps in low to mid 20s and a pesky +1 or + 2 degrees at 925

Only if low could be further offshore and maybe just ride the Gulf Stream that’s further enough away.

 

[BelmontWX79]

IMO, I can see an area of enhanced snowfall just north of the sfc wedge front boundary. The bitterly cold air from the wedge lifts the advancing warm moist air from the southwest. The Euro showed it centered over much of the ATL metro where we saw 1+ inch per hour rates at the start of the storm. That's where much of the snow could pile up for many places.

Yes we've seen time and again the initial waa surge undermodelled with precip breaking out sooner than anticipated.

 

[NWMSGuy]

Just to give a comparison of the GFS totals vs EURO totals through hour 240:

 

[Downeastnc]

I'm not trying to rain on parades here at all I'm just telling you guys from experience you can watch all of the CAD you want and all of the sfc low tracks you want but the mid level features are your primary ptype drivers. The better hope to lock in snow/ip longer is to have an initial surge of fgen WAA that rapidly cools the column and out performs model expectations which can hold off the ever lurking mixing line longer than expected so you can pile up snow but even then if the 850 low is too far NW you eventually lose

Yeah the 850 seems like it is always at least 100-150 miles NW of the surface low in these storms which is why we need the surface low offshore lol....

 

[Hypsometric]

All of the “snow” in atlanta is probably sleet

Thicknesses were clearly supportive of at least mostly snow. Kuchera map also considers the max column temperature, another check on the presence of any warm nose through the column from 500mb and below.

 

[griteater]

The JMA saves the day (for some)

 

[SD]

Yeah the 850 seems like it is always at least 100-150 miles NW of the surface low in these storms which is why we need the surface low offshore lol....

We could use about 1 state later on the negative tilt

 

[deltadog03]

The storm I would compare it to right now is the storm in February 2015 that absolutely lit up north AL and GA except a little farther south with the chance of going even farther south.

I'm not trying to rain on parades here at all I'm just telling you guys from experience you can watch all of the CAD you want and all of the sfc low tracks you want but the mid level features are your primary ptype drivers. The better hope to lock in snow/ip longer is to have an initial surge of fgen WAA that rapidly cools the column and out performs model expectations which can hold off the ever lurking mixing line longer than expected so you can pile up snow but even then if the 850 low is too far NW you eventually lose

Perfect post. Have to know that warm nose will be around and hard to pickup until almost game time.

 

[RainlessSnowless & Grumpy]

Isn't the problem up in RDU timing? This slowed down and gave the 50/50 more time to pull north and high pressure to slide east and then a north pull with the low and eroding CAD?

 

[SD]

Isn't the problem up in RDU timing? This slowed down and gave the 50/50 more time to pull north and high pressure to slide east and then a north pull with the low and eroding CAD?

Not really the stronger earlier negative tilt pulled the whole thing far enough west that we eat WAA in the mid levels. If it were to go negative over say Macon or Augusta instead of Birmingham rdu would be back in the game for a more significant system

 

[Showmeyourtds]

Perfect post. Have to know that warm nose will be around and hard to pickup until almost game time.

Are these the kind of things we find out about during special balloon releases? IE- there's a warm layer @ 900mb that may or may not go away before the precip does?

 

[NE Ga Wx]

This set up looks fantastic. A few things that I have learned over the years (this is NE GA/Upstate Specific):

1. being in the bullseye this far out is not always a good thing
2. We have not really seen a storm like this modeled for a couple of years so it is exciting to see, however, there will be shifts as we get closer to the event. those shifts will make a big difference between the type and amount of precip that falls
3. what I see is the potential for a great winter storm for much of the Southeast, and with fairly cold temps for a storm for this area. the set up appears to be going along what the "typical" set up is for much of N GA to get frozen precipitation. I am following this closely and am hopeful
4. the storm may "disappear" from the models for a while and then show back up as we get closer

all in all this looks to be the best chance for a lot of the board in a couple of winters

 

[bouncycorn]

Y’all ready for this big one??

 

[CaryWx]

Not really the stronger earlier negative tilt pulled the whole thing far enough west that we eat WAA in the mid levels. If it were to go negative over say Macon or Augusta instead of Birmingham rdu would be back in the game for a more significant system

Yeah, that northern energy coming out of Canada is being modeled stronger and picking up that wave earlier. This was not on the previous runs as much.

 

[Stormdoc]

Not really the stronger earlier negative tilt pulled the whole thing far enough west that we eat WAA in the mid levels. If it were to go negative over say Macon or Augusta instead of Birmingham rdu would be back in the game for a more significant system

Ultimately, don’t we need to simply hope for a less strong and consolidated energy, so that it does not tilt negative so soon?

 

[Cary_Snow95]

We could use about 1 state later on the negative tilt

Which is beyond reasonable given we’re still 90+ hours to it tilting

 

[Myfrotho704_]

Not really the stronger earlier negative tilt pulled the whole thing far enough west that we eat WAA in the mid levels. If it were to go negative over say Macon or Augusta instead of Birmingham rdu would be back in the game for a more significant system

Yep, we’re honestly closer to a dec 2002 then a mar 1980, I’m sure many see snow and accumulating snow (especially in favored areas in Miller Bs) but this is turning icy

 

[RainlessSnowless & Grumpy]

Not really the stronger earlier negative tilt pulled the whole thing far enough west that we eat WAA in the mid levels. If it were to go negative over say Macon or Augusta instead of Birmingham rdu would be back in the game for a more significant system

I haven't looked at it much other than the pretty maps on here, but if the CAD isn't retreating then I kind of agree with what Allan Huffman said on Twitter that he doesn't buy the low riding that far inland with that strong of a CAD in place. It seems to be in a good spot off of SC then goes due north into the NC coastal plain. That has to be an odd track right? I want to see this thing just as modeled for GA and SC but then move ne of the NC coast and dump 6-10 all the way from ATL to RDU. But that may be wishcasting idk

 

[deltadog03]

Are these the kind of things we find out about during special balloon releases? IE- there's a warm layer @ 900mb that may or may not go away before the precip does?

Yes. They will help find out what is going on in the different layers

 

[Deleted member 609]

Aleeeeet DT not buying the inland track for what its worth