Mid to Long Range Discussion ~ 2024

[wncsnow]

1 hour ago, WinstonSalemArlington said:

Look at that snow predicted over the open Atlantic 

[wncsnow]

1 hour ago, GaWx said:

1. Thanks. But operationals are almost always jumpy at 240+. So, I put little importance on operationals days 10+, when I prefer ensemble means.

2. So, looking at 12Z Euro/GFS/CMC ens means, the trof is ~80W/near our longitude.

3. Would it be too dry for the SE to get a synoptic scale winter storm with the mean trof near 80W? I’d say yes in many cases, especially when there’s just the N stream keeping it dry. I’d then prefer it be ~90W.  However, an often hard to prog (more than a few days out on models) short-wave induced split flow underneath the N stream would be a way to make it moist while the N stream to the north keeps the cold air in place at the sfc.

4. Here are 9 examples of moist split flow just in advance of SE winter storms even with the N trof even further east in all but one case:

12/8/18: (El Niño) N trof 72W but WSW flow SE

 

12/8/17: (La Nina) N trof 85W but SW flow SE

1/21/16: (El Niño) N trof 70W but WSW flow SE

 

2/25/15: (El Niño) N trof 77W but WSW flow SE

1/9/11: (La Nina) N trof 70W but incoming SW flow underneath

 

2/11/10: (El Niño) N trof 65W but incoming WSW to SW flow underneath

 

1/29/10: (El Niño) N trof 70W but incoming SW flow underneath

 

2/25/04: (warm neutral) N trof 70W but SW flow SE

1/9/04: (warm neutral) N trof 60W but WSW flow SE

 

5. Could there be a shortwave induced moist split flow underneath the progged 10-15+ day +PNA induced cold mean E trof coming that can’t yet be seen on ens H5 means? It’s very possible. Would I bet on it? No because we’re in La Nina, when it is more difficult to get a split flow. If this were El Niño with a frequent moist S stream, I’d be more excited. Regardless, sometimes these occur during La Nina like in 2 cases posted above, 12/8/17 and 1/9/11. Also, the progged couple of week long cold dominated period as opposed to just one and done helps. Plus there are obviously other ways to get a winter storm. So, keep hope alive, folks!

 

I don't disagree with any of this. Most of your examples had robust shortwaves though and we are not seeing that in the long range yet. We might need a lee trough super Clipper scenario to score in the leeside areas. But that was an El Niño winter

https://products.climate.ncsu.edu/weather/winter/event/

[BooneWX]

6 minutes ago, wncsnow said:

Look at that snow predicted over the open Atlantic 

The first wave is definitely going to be OTS but that second wave will be worth watching 

[BooneWX]

Just now, wncsnow said:

 

I don't disagree with any of this. Most of your examples had robust shortwaves though and we are not seeing that in the long range yet. We might need a lee trough super Clipper scenario to score in the leeside areas. But that was an El Niño winter

https://products.climate.ncsu.edu/weather/winter/event/

A couple of weeks ago I mentioned in the foothills thread that 1/30 clippers equates to snow in the foothills and this was the exact storm I had in mind. Thank you for finding it! 

[wncsnow]

1 minute ago, BooneWX said:

A couple of weeks ago I mentioned in the foothills thread that 1/30 clippers equates to snow in the foothills and this was the exact storm I had in mind. Thank you for finding it! 

The flow was similar to what's progged on models.  It was super cold after that Clipper. One of the few times (only?) it snowed Aspen type powder here. The wind blew most of it away (and sublimated) the following day even though it was 7-8 inches here and stayed in the low 20s the day after. 

 

[BooneWX]

1 minute ago, wncsnow said:

The flow was similar to what's progged on models.  It was super cold after that Clipper. One of the few times (only?) it snowed Aspen type powder here. The wind blew most of it away (and sublimated) the following day even though it was 7-8 inches here and stayed in the low 20s the day after. 

 

Back in the good ol days where you could count on at least 2-3 events per year minimum in the foothills 

[wncsnow]

4 minutes ago, BooneWX said:

Back in the good ol days where you could count on at least 2-3 events per year minimum in the foothills 

We used to get a lot of 3-5 inch snow/sleet/zr events now it's usually nothing or one big snow per season. 

 

2016- one big snowstorm

2018- one big snowstorm

2022- one big snowstorm 

2020, 2023, 2024- nothing 

[mercurydime]

49 minutes ago, wncsnow said:

 

I don't disagree with any of this. Most of your examples had robust shortwaves though and we are not seeing that in the long range yet. We might need a lee trough super Clipper scenario to score in the leeside areas. But that was an El Niño winter

https://products.climate.ncsu.edu/weather/winter/event/

A South Mountains Special right there.  

[wncsnow]

6 minutes ago, mercurydime said:

A South Mountains Special right there.  

I wish we got surprises like that still. Last surprise snow here was 2010 I think. I wasn't living here but I remember there being 3 or 4 inches of snow when none was forecast in December. I think there is a thread on it here too. 

[SnowDawg]

51 minutes ago, wncsnow said:

I wish we got surprises like that still. Last surprise snow here was 2010 I think. I wasn't living here but I remember there being 3 or 4 inches of snow when none was forecast in December. I think there is a thread on it here too. 

I remember a surprise sometime in that time frame too, one I'm remembering could've been in 2011/12 though not sure. I remember being forecasted flurries and then getting stuck at a friend's house with 4 or so inches. At least for us N GA and Upstate SC folks I'd call February 8th, 2020 a surprise, especially by modern standards. Most went to bed forecast  rn/sn no accumulation, then woke up to WSW's and ended up with 3-6.

[BooneWX]

40 minutes ago, SnowDawg said:

I remember a surprise sometime in that time frame too, one I'm remembering could've been in 2011/12 though not sure. I remember being forecasted flurries and then getting stuck at a friend's house with 4 or so inches. At least for us N GA and Upstate SC folks I'd call February 8th, 2020 a surprise, especially by modern standards. Most went to bed forecast  rn/sn no accumulation, then woke up to WSW's and ended up with 3-6.

That was a fun night on this forum. My day time temp hit the low 50s and we crashed to 31 under dynamic cooling. Had around 4 inches of paste living in Burke County at that time. 
 

Edit: I’ve got the wrong storm. I’m thinking Feb 6, 2021. Upstate and western Nc got nailed that evening. 

[GaWx]

The 0Z EPS mean is much colder than the 12Z and is the coldest of any yet. For example, much of the Carolinas are ~9F BN over the 9 days Jan 2-10! That long of a period is categorized unofficially as cold for an ensemble mean. The E US easily has the coldest anomalies of anywhere on the globe for Jan 2-10 overall!
 Thus, I’ll be surprised if tomorrow’s weeklies aren’t the coldest yet for the week of 1/6–12.

 The southern extent of the measurable snow mean is about the furthest south yet of any EPS run with it reaching much of the Gulf/SE coasts keeping in mind that the EPS is the most conservative of the 3 major ensembles:

 

 The typically more liberal GEFS (0Z) has the measurable down to @pcbjr’s abode in Hogtown! This is about as far south as I can recall even the GEFS mean ever going in the FL peninsula:

[NorthHillsWx]

It goes without saying, seeing those snow maximums on the ensembles over the water should concern everyone in this upcoming pattern. 

[CentralNC]

22 minutes ago, NorthHillsWx said:

It goes without saying, seeing those snow maximums on the ensembles over the water should concern everyone in this upcoming pattern. 

Let the NW trend begin!

[olafminesaw]

A much better signal for around the 6-8th of January on the 6z gefs

[PackGrad05]

EPS probabilities (00Z 27 Dec) indicate about 33% chance of 1" of snow for RDU...primarily from the 1/9-1/10 system.

 

[SnowDawg]

At least for as far as we can reliably see, I think we really need that 6th-10th system to be the one. Late week two and week 3 of January could still hold promise but I hate betting on an unseeable future, when that timeframe is just a few small ticks from paydirt.

[olafminesaw]

In other news...

[tarheelwx]

Olafminesaw,

Do you mind interpreting what you're seeing here?  Big hail risk?

 

Thanks, 

TW

[eyewall]

7 minutes ago, tarheelwx said:

Olafminesaw,

Do you mind interpreting what you're seeing here?  Big hail risk?

 

Thanks, 

TW

Tors

[BooneWX]

You have to pay the severe weather tax anytime ahead of a cold period 

[tarheelwx]

Thanks Eyewall.  Can you teach here? 

• I see the radar imagery showing strong storms or even super cells. 
• The Hodograph seems to be showing some sort of rotation, but the rotation appears to be clockwise instead of counter clockwise. 
• I see the the cold pocket up at about 18,000'.  

Which of the above is indicative of the tornado risk?

Thanks in advance.

TW

[Upstate Tiger]

12Z GFS pretty consistent with bringing the cold south and east through the end of the run.  We'll just have to wait and see on the storm chances.  I think we will have an opportunity or 2.  

[Epps88]

12z GFS definitely shows the potential as we go into the first week or so of the New Year. The models will be fun to watch in the coming days.

Sent from my SM-S926U using Tapatalk

[SnowDawg]

That GFS run really showed what a good -NAO can do for us if it can really be that persistent. I often feel like the effects of that kind of blocking are poorly modeled in the long range, so will be interesting to watch going forward.

[wncsnow]

The models are starting to show a quick warmup after the initial cold push and a likely rain storm with the next front around January 6th/7th, 

[wncsnow]

[suzook]

Well, we have the precip available for a couple events, but it doesn't seem like it will be cold enough for most during the events. Plenty of time though to have that change.