OT (Updated): The Saturday 1/11 Event Now Looking Like <1" with a Whiff Possible on the Low Side and 1-2" Possible on the High Side

[RU848789]

Continuing the discussion we've had going on in the pattern thread, thought it was finally time for a thread on the 1/11 event, given we're now just 4 days away and the global models have come into somewhat better agreement on the threat. Specifically, at 12Z, most models are now showing at least 1-2/2-4" for the DC-Boston megalopolis, i.e., the GFS/Euro/ICON and the GFS/Euro/CMC ensemble means show this, but the UK is still a miss to our SE and the CMC gives us <1" but has 2-4" only 50-75 miles SE of 95, which is much closer than the UK is.

IMO and in the opinions of many pros on weather boards/twitter/etc., this means that a minor (1-2") to moderate (2-4") event is quite possible for the Philly-NJ-NYC area, even if a major snowstorm (8-12" or more) is still pretty unlikely (as is a whiff). Also, temps should be below 32F and likely in the 20s for the event, so whatever falls will accumulate on all untreated surfaces; start time would likely be in the pre-dawn hours on Saturday and precip would likely go through the afternoon.

https://rutgers.forums.rivals.com/t...or-most-of-january.287192/page-4#post-7087291

More importantly, the Euro made a big jump towards the GFS at the upper levels and surface and is no longer tracking way out to sea, but not that far SE of us, like the GFS, plus the ensembles of the major models are all showing at least some snow for us now, so the likelihood of a complete whiff has gone down significantly. However both a whiff and a major snowstorm are still possible if quite unlikely (and there are more than a few ensemble members - maybe 20-30% - showing 6"+ for our area, so a significant to major storm is still not dead yet).

Not going to post a bunch of maps given that they're going to change (and for my money they clutter the thread up), but I am posting the NBM (model blend) map, as it does a pretty good job of averaging out what we're seeing in the global models (better than the NBM did 4 days out for the last storm). Clearly this shows a general 1-3" event for the area, with the higher end amounts generally closer to the coast, as seen in the models. And the AmericanWx thread on this event is linked below, where people post tons of snowfall maps (including me, lol).

https://www.americanwx.com/bb/topic/61463-jan-11th-12th-super-bomb-or-super-bummed/

Lastly, below is a great analysis of what's going on meteorologically by Tomer Burg, including why this system is much more complex and unpredictable 5 days out than yesterday's storm was.



Changed thread title to current title from: "OT: Minor to Moderate Snowfall Possible for Saturday 1/11 (a whiff or major snow still possible, if unlikely)"

 

[bac2therac]

why are using the term unlikely and why do you continue to use that useless NMB...its basically taking an outlier skewing the data

the ukie is a whiff, the euro is similar or even less than yesterday. The GFS is about 2 inches for central jersey and since it showed 2 feet a few runs ago maybe we shouldnt rally around it. The Icon is not a serious model. The CMC is on board but the GGEM isnt.

a potential for an event but its totally unknown at this point and just as likely to be a whiff as it is to give us 2 inches

 

[Knight Shift]

@e5fdny can thank me for the new thread.

 

[RU848789]

why are using the term unlikely and why do you continue to use that useless NMB...its basically taking an outlier skewing the data

the ukie is a whiff, the euro is similar or even less than yesterday. The GFS is about 2 inches for central jersey and since it showed 2 feet a few runs ago maybe we shouldnt rally around it. The Icon is not a serious model. The CMC is on board but the GGEM isnt.

a potential for an event but its totally unknown at this point and just as likely to be a whiff as it is to give us 2 inches

The NBM is not useless - why else would the NWS rely on it so heavily? One just has to understand it can be a bit time-lagged (which I didn't know until recently), which dampens the response to major changes for a suite, which is probably a good thing mostly. And it's not taking an outlier at all - it has over 20 model inputs. Maybe read up on some of this stuff.

And I don't really care what the Euro or GFS was yesterday, since current model runs are always more relevant than old ones - do you rely on old info to do your bracketology? Didn't think so. Models, generally, become more accurate as we get closer to the event. Doesn't mean 1-2/2-4" is a lock - didn't say it was - but it's looking much more likely with the latest op and ensemble member runs and 1-2" is certainly now more likely than a whiff. Also, the CMC is the GGEM, so no idea what you're talking about on that one.

 

[fsg2]

I'm just happy to see we've momentarily dispensed with lame trolling and personal attacks to get back to vigorous arguing over an inch or two of snow. Feels like old times.

 

[bac2therac]

The NBM is not useless - why else would the NWS rely on it so heavily? One just has to understand it can be a bit time-lagged (which I didn't know until recently), which dampens the response to major changes for a suite, which is probably a good thing mostly. And it's not taking an outlier at all - it has over 20 model inputs. Maybe read up on some of this stuff.

And I don't really care what the Euro or GFS was yesterday, since current model runs are always more relevant than old ones - do you rely on old info to do your bracketology? Didn't think so. Models, generally, become more accurate as we get closer to the event. Doesn't mean 1-2/2-4" is a lock - didn't say it was - but it's looking much more likely with the latest op and ensemble member runs and 1-2" is certainly now more likely than a whiff. Also, the CMC is the GGEM, so no idea what you're talking about on that one.

you said most models showing 2-4 inches that isnt the case really.

you already were warned about the nbm and i dont think it should be used 4 days out, maybe under 48 hours is when it actually matters

what models are showing 2-4 inches for here..show us and then show how many are showing an inch or less

im just saying pretty much all options are on the table except a major storm since no model is currently showing that....

 

[DJ Spanky]

I'm just happy to see we've momentarily dispensed with lame trolling and personal attacks to get back to vigorous arguing over an inch or two of snow. Feels like old times.

Yeah, but your happiness will be short lived if the latest models predict that a foot and a half or maybe two inches will fall on Central Jersey if the storm doesn't make a left turn at Albuquerque while out hunting for wabbits.

 

[Tango Two]

US National Weather Service Philadelphia/Mount Holly:​

We've been getting a lot of questions about the potential weekend winter storm. To answer those questions, there is about a 50-60% chance of snow.

That's all we know. We do NOT know how much snow we'll be getting yet.

The storm is still 4 days away, and a lot can change.

Could we get significant amounts? Sure, but there's still a chance we end up getting insignificant amounts. Greatest threat is Friday night and Saturday morning.

Keep an eye on the forecast in the coming days for more information!

 

[DJ Spanky]

So, to summarize, some snow might or might not fall.

 

[RU848789]

you said most models showing 2-4 inches that isnt the case really.

you already were warned about the nbm and i dont think it should be used 4 days out, maybe under 48 hours is when it actually matters

what models are showing 2-4 inches for here..show us and then show how many are showing an inch or less

im just saying pretty much all options are on the table except a major storm since no model is currently showing that....

One last try - if you're not going to read what I post, replying is useless. I didn't say most models are showing 2-4". I said most showing 1-2/2-4" and listed them, i.e., the GFS/Euro/ICON and the GFS/Euro/CMC ensemble means (and the NBM), but not the UK or CMC. You know how to access them.

And there was one met who said the NBM wasn't the best, but several others have told me (including a met on TOS who was at the NWS for 30+ years forecasting all over the US and a few others on 33) they like the NBM maps, but said one has to understand its limitations, which I now understand better.

We agree all options are on the table, but most pros are saying the minor to moderate outcomes are more likely than a whiff or a major event, which is all I'm saying. You're welcome to disagree. And a major, while pretty unlikely, is not off the table, given so many ensemble members are showing a major snowstorm, even if the Op models aren't currently showing that (as said by many mets).

 

[RU848789]

US National Weather Service Philadelphia/Mount Holly:​

We've been getting a lot of questions about the potential weekend winter storm. To answer those questions, there is about a 50-60% chance of snow.

That's all we know. We do NOT know how much snow we'll be getting yet.

The storm is still 4 days away, and a lot can change.

Could we get significant amounts? Sure, but there's still a chance we end up getting insignificant amounts. Greatest threat is Friday night and Saturday morning.

Keep an eye on the forecast in the coming days for more information!

That graphic showing 40" being possible might be the most irresponsible thing I've ever seen from the NWS. The text is fine. 40" is theoretically possible, but way, way less likely than 0" and is going to make some say the NWS says 40" is on the table.

 

[RUPete]

That graphic showing 40" being possible might be the most irresponsible thing I've ever seen from the NWS. The text is fine. 40" is theoretically possible, but way, way less likely than 0" and is going to make some say the NWS says 40" is on the table.

They're trying to have a little fun with the morons who run with the snow maps and point out how absurd it is to do that.

 

[MGSA99]

It's all over the news here in Greenville, SC. Could be the first significant snowfall in years around here. Or it could be a bust. Or worse, ice.

 

[Zak57]

It's all over the news here in Greenville, SC. Could be the first significant snowfall in years around here. Or it could be a bust. Or worse, ice.

How's Greenville doing from hurricane recovery? I've heard some different stuff on if it took a beating or not. Don't need a storm like that to make things worse.

 

[DHajekRC84]

So, to summarize, some snow might or might not fall.

And as usual a day before it could be 6 inches or a dusting. Great for the heads up stuff. These 1000 word posts are just so over the top and unreadable.

 

[RU848789]

It's all over the news here in Greenville, SC. Could be the first significant snowfall in years around here. Or it could be a bust. Or worse, ice.

Significant ice risk, unfortunately - below is just one model run, but the point is it shows there's ice risk. I'm sure the amount and location will change multiple times over the next 4 days.

 

[RU848789]

They're trying to have a little fun with the morons who run with the snow maps and point out how absurd it is to do that.

Maybe, but they've deleted it from their FB post, because I'm sure someone in the NWS kicked someone's butt over the irresponsibility of posting a graphic showing "0-40" of snow possible." I get humor, but not really in the world of public safety, unless it's blindingly obvious, i.e., if the graphic had smilies in it or had some comment noting that they were joking.

 

[RU848789]

And as usual a day before it could be 6 inches or a dusting. Great for the heads up stuff. These 1000 word posts are just so over the top and unreadable.

You could just read the title or the first paragraph and get the same short message without wading through the rest, which I put up for those who are interested in the details.

 

[RU848789]

For those outside of our area, below is the NBM (blend of models) showing the estimated snowfall from late Thursday night through Saturday for the southern tier; note that the NBM also has much less freezing rain than the NAM model I posted above, although the NAM is known for being pretty good with warm air advection aloft leading to sleet/ZR. This is probably the most useful estimate right now, since most NWS offices haven't put out snowfall forecasts yet (they don't do that until within 48 hrs normally), although the offices from about Dallas to Memphis have put up winter storm watches already. As an aside, the forecast for the southern tier is pretty solid since there's a lot less uncertainty about the storm crossing from Mexico/SW Texas to about SC/NC - beyond that, when it might impact us, is more uncertain.

 

[DJ Spanky]

Significant ice risk, unfortunately - below is just one model run, but the point is it shows there's ice risk.

 

[mikemarc1]

you said most models showing 2-4 inches that isnt the case really.

you already were warned about the nbm and i dont think it should be used 4 days out, maybe under 48 hours is when it actually matters

what models are showing 2-4 inches for here..show us and then show how many are showing an inch or less

im just saying pretty much all options are on the table except a major storm since no model is currently showing that....

A major storm is still on the table. Though at this stage - unlikely

 

[RU848789]

Dan Zarrow

❄❄❄ WEEKEND STORM UPDATE ❄❄❄

In this morning's edition of the CMDZ weather blog, I laid out 3 scenarios for this weekend's much-hyped possible storm:
1.) Glancing Blow, Light Snow
2.) Full-Blown Nor'easter
3.) Complete Miss

I listed the chances of those scenarios happening as 40% / 30% / 30%, respectively. Giving a slight edge to the light-moderate snow event outcome. As of this afternoon, there is not a single forecast model that paints the big, bad, hypeworthy blizzard scenario (#2). They've pretty much all settled on <6" centered on Saturday morning. Not a slam dunk guarantee, of course, but that is the clear trend.

So let's amend those scenario probabilities to something like 60% / 20% / 20%. I'll update that again tomorrow morning. And then we'll start thinking about potential accumulations and snow maps either tomorrow evening or (more likely) Thursday morning.

Thanks, Loyal - replying to your post in this thread, which is the active one for 1/11. Dan and I are apparently well aligned, as he now has 20% chance of a bomb (6-24"), a 60% chance of light snow (1-4") and a 20% chance of nada and I've said the 1-4" amounts are most likely with the bomb and nada being unlikely, but possible. The NWS is also much more bullish on a light to moderate event than they were this morning (same as I was before seeing today's 12Z models), as per today's 4 pm discussion, below.

https://nj1015.com/nj-stays-frozen-and-windy-3-possible-scenarios-for-weekend-storm/

Area Forecast Discussion
National Weather Service Mount Holly NJ
315 PM EST Tue Jan 7 2025

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

For Friday night and Saturday...A strong upper-level trough is
forecast to be sliding across south-central Canada to start
Saturday, however this trough has energy trailing back into the
southern Plains to northern Mexico. As this shifts eastward,
potentially strong energy and upper-level flow may result in the
trough becoming negatively tilted as it slides across the Northeast
and Mid-Atlantic or moreso once off the coast. This will drive
surface low pressure from the western Gulf coast east or
northeastward through Saturday. The track looks to be to our south
and east, however the exact track details will highly depend on the
strength of the upper-level trough and whether or not trailing
southern energy phases into it northward. If a full phase occurs
prior to the East Coast, then a significant storm would increase,
however the flow may be on the faster side which keeps from a full
phase from happening or it occurs to late. This would result in a
slower strengthening surface low as it slides by our region. The
overall ensemble guidance points to a storm, however the impacts on
our region will depend on the track as the timing of the features
aloft will be key. There is enough of a consensus though to raise
PoPs into the low likely range for much of our region late Friday
night and the first part of Saturday. The timing however does differ
some with some guidance slower than others. As of now, the air mass
looks cold enough to result in snow as the precipitation type,
however this will depend on the track as a more northward shift (or
tucked in surface low) could bring in some warming especially closer
to the coast.

 

[Tango Two]

"Latest models phase the storm too late which give the region just a glancing blow with most of the snow just staying offshore. 100 miles difference in track is all it will take to get snow. Still time for adjustments, but odds are favoring the more out to sea scenario."

 

[Greene Rice FIG]

40 is a big number

 

[MGSA99]

How's Greenville doing from hurricane recovery? I've heard some different stuff on if it took a beating or not. Don't need a storm like that to make things worse.

We're doing fine. Only remnants around here are the large piles of chainsawed trees on the side of the road. It's the mountains of the Asheville area that are going to take years to recover. It was a storm that moved fast so it didn't have time to weaken like most hurricanes do when they come through this area.

 

[RULoyal]

Dan Zarrow

❄❄❄ WEEKEND STORM UPDATE ❄❄❄

In this morning's edition of the CMDZ weather blog, I laid out 3 scenarios for this weekend's much-hyped possible storm:
1.) Glancing Blow, Light Snow
2.) Full-Blown Nor'easter
3.) Complete Miss

I listed the chances of those scenarios happening as 40% / 30% / 30%, respectively. Giving a slight edge to the light-moderate snow event outcome. As of this afternoon, there is not a single forecast model that paints the big, bad, hypeworthy blizzard scenario (#2). They've pretty much all settled on <6" centered on Saturday morning. Not a slam dunk guarantee, of course, but that is the clear trend.

So let's amend those scenario probabilities to something like 60% / 20% / 20%. I'll update that again tomorrow morning. And then we'll start thinking about potential accumulations and snow maps either tomorrow evening or (more likely) Thursday morning.

 

[bac2therac]

The NBM is not useless - why else would the NWS rely on it so heavily? One just has to understand it can be a bit time-lagged (which I didn't know until recently), which dampens the response to major changes for a suite, which is probably a good thing mostly. And it's not taking an outlier at all - it has over 20 model inputs. Maybe read up on some of this stuff.

And I don't really care what the Euro or GFS was yesterday, since current model runs are always more relevant than old ones - do you rely on old info to do your bracketology? Didn't think so. Models, generally, become more accurate as we get closer to the event. Doesn't mean 1-2/2-4" is a lock - didn't say it was - but it's looking much more likely with the latest op and ensemble member runs and 1-2" is certainly now more likely than a whiff. Also, the CMC is the GGEM, so no idea what you're talking about on that one.

What are they relying on it for 4-5 days out...sure a storm signal but the amounts are irrelevant on this model

 

[WhiteBus]

40 is a big number

And the guy who posted it is a little number. No stars for that post!! 🤣

 

[RU848789]

Dan Zarrow

❄❄❄ WEEKEND STORM UPDATE ❄❄❄

In this morning's edition of the CMDZ weather blog, I laid out 3 scenarios for this weekend's much-hyped possible storm:
1.) Glancing Blow, Light Snow
2.) Full-Blown Nor'easter
3.) Complete Miss

I listed the chances of those scenarios happening as 40% / 30% / 30%, respectively. Giving a slight edge to the light-moderate snow event outcome. As of this afternoon, there is not a single forecast model that paints the big, bad, hypeworthy blizzard scenario (#2). They've pretty much all settled on <6" centered on Saturday morning. Not a slam dunk guarantee, of course, but that is the clear trend.

So let's amend those scenario probabilities to something like 60% / 20% / 20%. I'll update that again tomorrow morning. And then we'll start thinking about potential accumulations and snow maps either tomorrow evening or (more likely) Thursday morning.

FYI, I quoted your post above a few posts - thought you'd see it...

 

[RU848789]

Well, the more limited 18Z suite has moved back towards less snow for our area with the Euro and ICON now just having <1" area-wide, although the GFS looked similar to 12Z with a 1-3/2-4" event for most, especially toward the coast; in addition the important GFS and Euro ensemble means also stepped back on snowfall, which is not a good sign. However, moves like this are relatively common this far out (we actually had a similar move towards less snowy at the exact same point - about 90 hrs out - for the 1/6 event).

Having said that, unless 0Z moves back towards 12Z, my guess is most will, rightly, back down a bit on snowfall forecasts/likelihood for our area based on 18Z and a perhaps similar to 18Z suite at 0Z tonight and we might then be in the same boat we were in for this past event for areas N of 276/195, i.e., snow lovers hoping for 1-2" of snow and <1" for everyone being a more probable outcome. We'll see in about 5 hours. It's never easy getting snow in these parts, but I still find the tracking part to be fascinating.

Note that there were not significant changes in modeled snowfall for the first part of the storm, i.e., from Texas through NC, as I expected and explained above, since the first part of the storm is 1+ day closer and less prone to sensitivity given the simpler setup for that.

 

[T2Kplus20]

why are using the term unlikely and why do you continue to use that useless NMB...its basically taking an outlier skewing the data

the ukie is a whiff, the euro is similar or even less than yesterday. The GFS is about 2 inches for central jersey and since it showed 2 feet a few runs ago maybe we shouldnt rally around it. The Icon is not a serious model. The CMC is on board but the GGEM isnt.

a potential for an event but its totally unknown at this point and just as likely to be a whiff as it is to give us 2 inches

Wishcasting 101.

 

[DJ Spanky]

 

[RocktheRac]

Thanks, Loyal - replying to your post in this thread, which is the active one for 1/11. Dan and I are apparently well aligned, as he now has 20% chance of a bomb (6-24"), a 60% chance of light snow (1-4") and a 20% chance of nada and I've said the 1-4" amounts are most likely with the bomb and nada being unlikely, but possible. The NWS is also much more bullish on a light to moderate event than they were this morning (same as I was before seeing today's 12Z models), as per today's 4 pm discussion, below.

https://nj1015.com/nj-stays-frozen-and-windy-3-possible-scenarios-for-weekend-storm/

Area Forecast Discussion
National Weather Service Mount Holly NJ
315 PM EST Tue Jan 7 2025

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...

For Friday night and Saturday...A strong upper-level trough is
forecast to be sliding across south-central Canada to start
Saturday, however this trough has energy trailing back into the
southern Plains to northern Mexico. As this shifts eastward,
potentially strong energy and upper-level flow may result in the
trough becoming negatively tilted as it slides across the Northeast
and Mid-Atlantic or moreso once off the coast. This will drive
surface low pressure from the western Gulf coast east or
northeastward through Saturday. The track looks to be to our south
and east, however the exact track details will highly depend on the
strength of the upper-level trough and whether or not trailing
southern energy phases into it northward. If a full phase occurs
prior to the East Coast, then a significant storm would increase,
however the flow may be on the faster side which keeps from a full
phase from happening or it occurs to late. This would result in a
slower strengthening surface low as it slides by our region. The
overall ensemble guidance points to a storm, however the impacts on
our region will depend on the track as the timing of the features
aloft will be key. There is enough of a consensus though to raise
PoPs into the low likely range for much of our region late Friday
night and the first part of Saturday. The timing however does differ
some with some guidance slower than others. As of now, the air mass
looks cold enough to result in snow as the precipitation type,
however this will depend on the track as a more northward shift (or
tucked in surface low) could bring in some warming especially closer
to the coast.

Maybe you and Dan should align for free t shirts at the RAC.

 

[bac2therac]

Well, the more limited 18Z suite has moved back towards less snow for our area with the Euro and ICON now just having <1" area-wide, although the GFS looked similar to 12Z with a 1-3/2-4" event for most, especially toward the coast; in addition the important GFS and Euro ensemble means also stepped back on snowfall, which is not a good sign. However, moves like this are relatively common this far out (we actually had a similar move towards less snowy at the exact same point - about 90 hrs out - for the 1/6 event).

Having said that, unless 0Z moves back towards 12Z, my guess is most will, rightly, back down a bit on snowfall forecasts/likelihood for our area based on 18Z and a perhaps similar to 18Z suite at 0Z tonight and we might then be in the same boat we were in for this past event for areas N of 276/195, i.e., snow lovers hoping for 1-2" of snow and <1" for everyone being a more probable outcome. We'll see in about 5 hours. It's never easy getting snow in these parts, but I still find the tracking part to be fascinating.

Note that there were not significant changes in modeled snowfall for the first part of the storm, i.e., from Texas through NC, as I expected and explained above, since the first part of the storm is 1+ day closer and less prone to sensitivity given the simpler setup for that.

i dont think anyone is actually putting snowfall forecasts out but you...lol

 

[bac2therac]

Maybe you and Dan should align for free t shirts at the RAC.

i thought for sure he would get the free tv last night

 

[T2Kplus20]

i thought for sure he would get the free tv last night

I wonder how many kids he knocked out of the way for those free shirts? Shameful.

 

[RU848789]

i dont think anyone is actually putting snowfall forecasts out but you...lol

Who's putting out snowfall forecasts? Certainly not me. I'm just discussing possibilities and assigning rough probabilities to them. Huge difference between that and a forecast. The only actual "predicting" I usually do is the snowfall for my house about a day before an event and guessing what the NWS is going to do in their next forecast, based on looking at the most recent models.

 

[DJ Spanky]

Who's putting out snowfall forecasts?

But the graphic above from TT said 0-40 inches!

 

[bac2therac]

Who's putting out snowfall forecasts? Certainly not me. I'm just discussing possibilities and assigning rough probabilities to them. Huge difference between that and a forecast. The only actual "predicting" I usually do is the snowfall for my house about a day before an event and guessing what the NWS is going to do in their next forecast, based on looking at the most recent models.

you said

Having said that, unless 0Z moves back towards 12Z, my guess is most will, rightly, back down a bit on snowfall forecasts/likelihood for our area based on 18Z

 

[bac2therac]

you said

Having said that, unless 0Z moves back towards 12Z, my guess is most will, rightly, back down a bit on snowfall forecasts/likelihood for our area based on 18Z

the point is no one is putting out any snowfall forecasts yet