Mid to Long Range Discussion ~ 2024

[Upstate Tiger]

LOL...The Rio Grande, Corpas Christi, and South Padre Island are the places to be!

Plenty of time for this to trend north and east 

 

[olafminesaw]

The GEFS members that have snow transfer and develope a new low near the coast which gets pulled inland by the interaction with the original low. A messy setup that could work in theory, but can't think of an analog where this worked out. The OP kinda has this evolution, it's just that the system gets pulled OTS to quickly, which would be the more plausible solution.

[GaWx]

 The ensemble means remain in agreement on the major pattern change at H5 to start ~Feb 13, when the +PNA first rapidly intensifies and which is consistent with what the extended models started showing over 3 weeks ago. So, as we see it getting closer with little or no can kicking, confidence increases. Within a few days, the SE gets cold on the models.

 For example from the 12Z GEFS: how often do SE 850s this cold show on day 16 of the GEFS?

 

 Now note on the 12Z GEFS map below the green area well to our WSW. That represents the El Niño supported moist subtropical jet. Combined with the cold transporting +PNA (cold aided by -AO/-NAO), we’d have a classic split flow, which is the most favorable pattern to induce the possibility of a GOM Miller A based major SE winter storm.

 Extended models have been suggesting the first enhanced chance for one of these ~Feb 18-19 based on examining the last few days of runs’ individual members’ SLPs. That green area is moving generally toward the E during the last frames. So, it’s possible that it would get to the SE then and allow the moist flow to overrun the SE cold.

 WSW to SW H5 flow over the SE is usually needed for a big widespread storm. We can get that kind of flow from that ST jet, which has WSW H5 flow, moving E. But the +PNA can’t be too overpowering or else H5 flow might remain W or WNW over the SE and thus be dry. And the cold can’t modify too much once the moist flow arrives or it could be too warm. Always the delicate balance/timing. But at least there’s an opportunity being strongly hinted during favorable Nino climo of mid to late Feb.

[NorthHillsWx]

If this upcoming ~2 weeks pattern doesn’t produce outside the mountains/foothills somewhere, I think there will be some serious questioning as to whether or not it can snow here anymore 

[BooneWX]

13 minutes ago, NorthHillsWx said:

If this upcoming ~2 weeks pattern doesn’t produce outside the mountains/foothills somewhere, I think there will be some serious questioning as to whether or not it can snow here anymore 

The foothills starving has been the most alarming thing for me. While I always root for the folks down east, it’s understandable how things tend to not work out that often just based on their physical location. Now the foothills are a different story. It should be working out more often than it has - absolutely gives me pause when climo regions need hail mary’s. 

[wncsnow]

2 hours ago, GaWx said:

 The ensemble means remain in agreement on the major pattern change at H5 to start ~Feb 13, when the +PNA first rapidly intensifies and which is consistent with what the extended models started showing over 3 weeks ago. So, as we see it getting closer with little or no can kicking, confidence increases. Within a few days, the SE gets cold on the models.

 For example from the 12Z GEFS: how often do SE 850s this cold show on day 16 of the GEFS?

 

 Now note on the 12Z GEFS map below the green area well to our WSW. That represents the El Niño supported moist subtropical jet. Combined with the cold transporting +PNA (cold aided by -AO/-NAO), we’d have a classic split flow, which is the most favorable pattern to induce the possibility of a GOM Miller A based major SE winter storm.

 Extended models have been suggesting the first enhanced chance for one of these ~Feb 18-19 based on examining the last few days of runs’ individual members’ SLPs. That green area is moving generally toward the E during the last frames. So, it’s possible that it would get to the SE then and allow the moist flow to overrun the SE cold.

 WSW to SW H5 flow over the SE is usually needed for a big widespread storm. We can get that kind of flow from that ST jet, which has WSW H5 flow, moving E. But the +PNA can’t be too overpowering or else H5 flow might remain W or WNW over the SE and thus be dry. And the cold can’t modify too much once the moist flow arrives or it could be too warm. Always the delicate balance/timing. But at least there’s an opportunity being strongly hinted during favorable Nino climo of mid to late Feb.

How does the EPS Look

[eyewall]

31 minutes ago, NorthHillsWx said:

If this upcoming ~2 weeks pattern doesn’t produce outside the mountains/foothills somewhere, I think there will be some serious questioning as to whether or not it can snow here anymore 

well if we don't get any measurable this winter it will likely be a record number of days by the time the next winter rolls around.

[StantonParkHoya]

18z GFS kind of interesting for coastal NC / ILM for next week

[KChuck]

57 minutes ago, eyewall said:

well if we don't get any measurable this winter it will likely be a record number of days by the time the next winter rolls around.

[eyewall]

Happy hour GFS in the right direction from 12z:

[knowledgeispwr]

1 hour ago, NorthHillsWx said:

If this upcoming ~2 weeks pattern doesn’t produce outside the mountains/foothills somewhere, I think there will be some serious questioning as to whether or not it can snow here anymore 

The climate trends our not our friends for those us east of the high terrain. Fingers crossed though!

[StantonParkHoya]

I’ll go ahead and do it: sun angle.

There. Cross it off the list. And yes, it’s very real if we’re borderline on temps.

[GaWx]

2 hours ago, wncsnow said:

How does the EPS Look

Consistent

[GaWx]

 The 12Z UKMET is further S than other models and the strongest by far with the upcoming storm. It is so strong that the text output classifies it as a tropical cyclone out in the Gulf despite it having no real tropical characteristics. Dewpoints are too low, SSTs are only in the low to mid 70s (see image below), and it is under a strong upper low.

But maps do suggest a slight low level warm/wet core vs its surroundings:

https://www.pivotalweather.com/model.php?m=ukmet&p=sfctd_b-imp&rh=2024013112&fh=108&r=conus&dpdt=&mc=

 On Sun evening the run has it max out with sustained winds at 59 knots/68 mph along with a SLP way down at 978 mb/28.85”. It looks to me like this UKMET run is likely on crack:

MET OFFICE TROPICAL CYCLONE GUIDANCE FOR NORTH-EAST PACIFIC AND ATLANTIC

             GLOBAL MODEL DATA TIME 1200UTC 31.01.2024

       NEW TROPICAL CYCLONE FORECAST TO DEVELOP AFTER  96 HOURS
              FORECAST POSITION AT T+ 96 : 26.9N  88.1W

                        LEAD                 CENTRAL     MAXIMUM WIND
      VERIFYING TIME    TIME   POSITION   PRESSURE (MB)  SPEED (KNOTS)
      --------------    ----   --------   -------------  -------------
    1200UTC 04.02.2024   96  26.9N  88.1W      993            44
    0000UTC 05.02.2024  108  28.3N  84.7W      978            59
    1200UTC 05.02.2024  120  29.1N  82.6W      981            44
    0000UTC 06.02.2024  132  28.6N  81.5W      990            40
    1200UTC 06.02.2024  144              CEASED TRACKING

[wncsnow]

1 hour ago, GaWx said:

Consistent

But not as cold as the GEFS right?

[GaWx]

8 minutes ago, wncsnow said:

But not as cold as the GEFS right?

 Wrong. The 12Z EPS 360 (last map of the run) is colder in the SE than the 12Z GEFS 360 and the 18Z GEFS 354 at both 2 meters and 850 mb. Check them out at Tropical Tidbits.

[wncsnow]

2 minutes ago, GaWx said:

 Wrong. The 12Z EPS 360 (last map of the run) is colder in the SE than the 12Z GEFS 360 and the 18Z GEFS 354 at both 2 meters and 850 mb.

Let's see if we can enjoy a week of below average 

[GaWx]

13 minutes ago, wncsnow said:

Let's see if we can enjoy a week of below average 

Do you have predictions for the second half of Feb (say, Feb 15-29) in Asheville with regard to both temperature anomaly and snowfall? If so, what are they?

[GaWx]

Brand new CANSIPS for Feb: colder than prior run in SE (as is also the case for Mar): keep in mind that this is based on the colder 1981-2010 climo (vs the warmer 1991-2020).

 

It not surprisingly has a mild ridgy Dec/Jan next winter with La Niña. So, enjoy El Niño while you can!

[CaryWx]

lol even Bermuda colder 

[lilj4425]

Bring on hurricane season. 

[Tacoma]

The groundhog will see his shadow tomorrow, so maybe we will finally see some winter weather.  

[NorthHillsWx]

Per ensemble guidance, the cold is delayed a bit till around the 17th. Will be interesting to watch to see if that timeframe holds as we get closer. Realistically that gives us about a week window to score before we really are fighting an uphill battle against climo. I know I know we’ve had snowstorms around march in the past, it’s just been so long I don’t even remember one so that’s not realistic to expect one. 17th-25th has my attention as our last gasp chance. Didn’t think that’s where we’d be on February 1st but that’s where we are

[eyewall]

7 minutes ago, NorthHillsWx said:

Per ensemble guidance, the cold is delayed a bit till around the 17th. Will be interesting to watch to see if that timeframe holds as we get closer. Realistically that gives us about a week window to score before we really are fighting an uphill battle against climo. I know I know we’ve had snowstorms around march in the past, it’s just been so long I don’t even remember one so that’s not realistic to expect one. 17th-25th has my attention as our last gasp chance. Didn’t think that’s where we’d be on February 1st but that’s where we are

The writing is on the wall at this point. A 2nd failed year in a row. We will go into record territory if we do end up with no measurable this winter.

[StantonParkHoya]

12 hours ago, wncsnow said:

Let's see if we can enjoy a week of below average 

Yep. And again, let’s remind folks that by the last week of Feb, the average high for Raleigh is about 60 damn degrees

[NorthHillsWx]

39 minutes ago, eyewall said:

The writing is on the wall at this point. A 2nd failed year in a row. We will go into record territory if we do end up with no measurable this winter.

2 year going on 3 years snowless if that week doesn’t produce, 6 years since 4”+ on a season. I know it’s the south but these are sobering numbers even for here. Boston and NYC are not doing much better this year as there have been no east coast storms. And this is during a strong El Niño. 
 

Some posters on here have been GREAT at posting and predicting LR pattern and that is great that there is a good pattern shaping up but holy moly, we’re 17 days away and have just burnt all of December-January and know we’re burning over half of February with 4 cold days total to show for it. This may somehow be worse than last year bc at least Enso brought our expectations up 

[GaWx]

1 hour ago, NorthHillsWx said:

Per ensemble guidance, the cold is delayed a bit till around the 17th. Will be interesting to watch to see if that timeframe holds as we get closer. Realistically that gives us about a week window to score before we really are fighting an uphill battle against climo. I know I know we’ve had snowstorms around march in the past, it’s just been so long I don’t even remember one so that’s not realistic to expect one. 17th-25th has my attention as our last gasp chance. Didn’t think that’s where we’d be on February 1st but that’s where we are

 I don’t see a delay based on the consensus. It appears to me that the 3 major ensembles are still suggesting ~Feb 15 for a cold front generated by a Canadian high to first reach the SE. The strong increase in a +PNA still starts ~Feb 13. Now regarding the potential for significant nonmountain wintry precip, that has generally been targeting on the extended models for quite some time ~Feb 18-19 for the first decent chance per following individual ensemble member tracks. Anyone can look back at my posts on this timing in this thread.
 The more difficult challenge imo will be to see whether or not the predicted cold will be accompanied by precip or else be dry. That’s often a challenge as Arctic air is by its nature dry. My hope is though that an El Nino induced split flow will set up the SE for a nice winter storm. But getting the right combo of features and the right timing is always a challenge. That’s why it often takes only one major storm to make for an AN snow season.

[lilj4425]

[GaWx]

 The late portion of the 12Z GFS was ugly. No two ways about it. Hopefully it will turn out to just be an outlier. Let’s see what the more credible late GEFS shows. 

[Terpeast]

41 minutes ago, GaWx said:

 The late portion of the 12Z GFS was ugly. No two ways about it. Hopefully it will turn out to just be an outlier. Let’s see what the more credible late GEFS shows. 

How so? It looks decent to me. Cold air boundary moving south with reinforcements over time