OT: Significant (CNJ) to Major (Along/N of 78) Winter Storm Likely on Tuesday (2/12-13; much less uncertainty on outcome)
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the euro is just one solution but if it verifies its bringing just 3-4 inches and its a weaker storm which effects the accumulation alot and i believe it was further south
whether its right is anyones guess
well its going to get in the 20s at night so all that wet slush going to freeze....wednesay will be cold, we wont top 40 and then a refreeze of melting but yeah low 40s toward the end of the week and things gradual melt
18z NAM was 6-8 Kuchera and 7-10 regular
18a 3k NAM was 4-6 Kuchera and 5-10 regular
if these runs were right then its moving south and those NW areas of NJ are not getting 12-18 inches
what a tough forecast with model mayhem less than 12 hours before event start time
18a 3k NAM was 4-6 Kuchera and 5-10 regular
if these runs were right then its moving south and those NW areas of NJ are not getting 12-18 inches
what a tough forecast with model mayhem less than 12 hours before event start time
This evening's updated maps will either be a huge change, or will solidify Mt Holly as 'not buying' the southern shift. 12-18 top of Sussex County? That's a bold strategy, Cotton...
Craig Allen
RANT-
We have entered into model absurdity leading to meteorological insanity. I'll make this quick; I have to get on air and say something and try to sound smart.
As of today's major runs and very latest meso/hi res updates, everything is seemingly being turned upside down. Like clothes in a dryer, the atmospheric pieces are still getting tossed around.
The euro has been horrendous. Normally the stalwart, it now has a weaker storm, much farther south again. In the past 3 days, it has changed it's solutions and placement more than the average person changes their underwear (What...you don't change your underwear 4 times a day, do you? )
If this is the case, you can totally forget about 6-12" in the northern suburbs. If the snow isn't heavy enough in the City, it won't stick b/c it will be too warm. 3-6" of 'heavier snow' will now line up south of I-78
18z HRRR/nam nest- the heaviest accumultions now run between I-80 and I-78 from EPA/WNJ across LI. But again, that's using 10:1 ratios. ...which most likely will not verify. Too warm here at the surface.
So I'm going to throw something against the wall and see what sticks and get on WCBS Newsradio 880 and come up with a forecast, which is sure to change again
RANT-
We have entered into model absurdity leading to meteorological insanity. I'll make this quick; I have to get on air and say something and try to sound smart.
As of today's major runs and very latest meso/hi res updates, everything is seemingly being turned upside down. Like clothes in a dryer, the atmospheric pieces are still getting tossed around.
The euro has been horrendous. Normally the stalwart, it now has a weaker storm, much farther south again. In the past 3 days, it has changed it's solutions and placement more than the average person changes their underwear (What...you don't change your underwear 4 times a day, do you? )
If this is the case, you can totally forget about 6-12" in the northern suburbs. If the snow isn't heavy enough in the City, it won't stick b/c it will be too warm. 3-6" of 'heavier snow' will now line up south of I-78
18z HRRR/nam nest- the heaviest accumultions now run between I-80 and I-78 from EPA/WNJ across LI. But again, that's using 10:1 ratios. ...which most likely will not verify. Too warm here at the surface.
So I'm going to throw something against the wall and see what sticks and get on WCBS Newsradio 880 and come up with a forecast, which is sure to change again
Let's summarize the 12Z models, and I'm using 10:1 ratios here, since if high intensity (>1"/hr) snowfall rates are observed as forecasted ratios would likely be in the 8-9:1 range, as crystal growth will be very good in the DGZ and melting will be overcome without too much loss, meaning the Kuchera/snow depth algorithms are too low IMO (shared by many mets), except near the edge of changeover areas near 195 and the coast where 6-7:1 will likely be more accurate. 10:1 maps also give one the exact amount of precip that falls as snow.
Anyway, the 12Z HRRR, NAM, and GFS are summarized in the quotes above (all 3 very snowy). The 12Z RGEM is not as snowy with a 5" line along 276/195 and 6-8" for most of NEPA/CNJ/NNJ/NYC/LI, while the 12Z CMC is similar to the RGEM on the low side, but has 12"+ along/N of 78 up to 84 (but W of the TPK).
Another model not discussed often, but which is considered pretty good, is the HREF (it's a mixture of high resolution model outputs), which shows a 4" line close to 276/195, a 6" line from Trenton to AP and a 10" line from New Hope to Rahway with 12-18" between 80 and 84.
However, we have a new fly in the ointment, as the 12Z UK and Euro both had much less precip than the other models. The UK only has 4-7" for most of the area down to 195/276 (and even down to Toms River) and <4" north of 80, while the 12Z Euro is fairly similar with 5-8" for most of CNJ/NYC and down to Toms River, but also with 2-4" N of 80 with less precip. Lack of intensity/precip has been my biggest reason for thinking the heavy snows might not work out, as this leads to less snow falling and more melting.
Given all of the above, I still think the NWS is too low south of 78 down to 276/195 and the coast and even further towards Philly and I will be very surprised if they and other media don't increase their snowfall amounts for those areas to something like what TWC has, below, but then again the UK/Euro might just give them enough pause to not make significant changes. That's why forecasting winter storms around here is so damn hard. I think the NWS amounts are great along/N of 78 with the 8" line basically being 78 and more north of there (unless the UK/Euro are right and N of 80 sees less snow/precip).
All of the snowfall maps are at this link:
https://www.americanwx.com/bb/topic...any-on-feb-13/?do=findComment&comment=7211123
Summary: a major winter storm is on our doorstep, but there are still model disagreements on the exact track and precip/snow amounts, so we need to keep an eye on future model runs and soon the radar and the evolution of the systems involved. The storm starts as rain for everyone in the late evening, but quickly turns to snow in NW areas and takes several hours to change over down towards 95 and the coast; for most of CNJ the snow will fall heavily from about 5 am through about noon. Basically, snowfall amounts of >8" are predicted along and N of 78 (with up to 12-14" N of 80) and most sources agree on that. South of 78 there is much more disagreement. I believe TWC map below, is more likely to be correct than the NWS map. TWC map is more bullish on getting 5-8" from 276/195 up to 78 and even 2-5" down to Philly over to Toms River up to 276/195, while the NWS is predicting more like 2-5" from 276/195 up to 78 and then only 1-2" along the Delaware SW of Trenton to Philly with very little S of 195 in NJ.
Details: So, given the significantly lower snowfall amounts on the Euro and UK (two very good models) vs. the generally greater snowfall amounts for most of the other models, the question is do forecasters do some kind of compromise or go with one camp or another or something else, as they have tools/knowledge most don't. Tough call, especially with the 18Z HRRR showing a huge snowstorm (10-16") for the entire area all the way down to Wilmington to LBI, but less for far NWNJ, as it shifted south maybe 50 miles, and the 18Z NAM also shifting things south a ways and with less precip (8-11" for most of the state, while the 18Z RGEM had 6-10" for everywhere N of 276/195. So there was some movement south but not by all of them and precip amounts weren't as low as on the Euro/UK so who knows? The 18Z models at least make it clear that there likely won't be some huge shift south as some had discussed
Anyway, as expected, the NWS-Philly did increase snowfall amounts south of 78, but not as much as I thought they should and they now have warnings up for Poconos/Sussex for 8-13" of snow, for the Lehigh Valley, Morris, Warren for 7-10" of snow and for Berks, NW Bucks, Hunterdon and Somerset for 4-7" of snow and they have advisories up for Middlesex, Mercer, Lower Bucks and Montco for 3-5" of snow and for Western Monmouth and Chester for 2-4" of snow. IMO, all of those places under advisories should be under warnings for 4-7" of snow, especially given the southward shift we've seen from some of the models which brings more snow further south, which would also likely decrease snowfall amounts by a coupe of inches N of 80. In addition, given that about half the models have 3-6" or more of snow for Philly and SNJ (even at lower ratios), I would expect those areas to at least be under advisories for 2-4" of snow.
Also, the NWS-NYC now has warnings up for Union/Essex/Hudson and NYC/LI for 4-8", warnings up for LI for 5-10", warnings for eastern Passaic, eastern Bergen and Western Essex for 7-10" of snow and warnings for W. Passaic, W. Bergen and the Hudson Valley north of the Bronx for 9-13" of snow (and for CT for 7-12"). It's certainly going to be fun to see this all evolve and for the rain then snow to finally come late tonight with possibly hellacious snowfall rates of 1-2" per hour from 4 am to noon with a quick shut off after that. I still think TWC map is better than the one from the NWS, but we'll see soon.
Tomorrow morning's rush hour has the potential to be extremely difficult from at least 276/195 up through 84 for all of EPA/CNJ/NNJ/NYC/LI/SENY/CT with very heavy snow falling with 8-12" or more along and N of 78 and very possibly up to 8" down to 276/195 which would mean over 1" per hour rates for the 8-9 hours of the snow falling - and even for areas with warmer temps and less accumulation on roads, visibility will be very hindered and roads in some places could become difficult to travel on, especially near/N of 78 and as I've said before where we see >1" per hour rates even at 33-34F, untreated roads will become snow covered as those rates will exceed melting rates.
Lastly, don't forget that minor to moderate coastal flooding is likely for DE/NJ/NY coasts on Tuesday and 40-45 mph winds are likely for coastal areas and 30-35 mph inland as the storm cranks on Tuesday. In addition, for areas that get 6"+ of heavy wet snow/paste that sticks to trees the weight along with the winds could lead to some downed trees/power lines and outages.
And don't forget to shovel before sunset and salt areas as needed, as temps will drop into the mid-20s. Also, be careful out there, but try to enjoy it if you can.
https://www.weather.gov/phi/
https://www.americanwx.com/bb/topic...winter-storm-6-12-for-many-on-feb-13/page/48/
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actually deleted that...its the same one from this morning but its about right could be more
Thanks #sSummary: a major winter storm is on our doorstep, but there are still model disagreements on the exact track and precip/snow amounts, so we need to keep an eye on future model runs and soon the radar and the evolution of the systems involved. Basically, snowfall amounts of >8" are predicted along and N of 78 (with up to 12-14" N of 80) and most sources agree on that. South of 78 there is much more disagreement. I believe TWC map below, is more likely to be correct than the NWS map. TWC map is more bullish on getting 5-8" from 276/195 up to 78 and even 2-5" down to Philly over to Toms River up to 276/195, while the NWS is predicting more like 2-5" from 276/195 up to 78 and then only 1-2" along the Delaware SW of Trenton to Philly with very little S of 195 in NJ.
Details: So, given the significantly lower snowfall amounts on the Euro and UK (two very good models) vs. the generally greater snowfall amounts for most of the other models, the question is do forecasters do some kind of compromise or go with one camp or another or something else, as they have tools/knowledge most don't. Tough call, especially with the 18Z HRRR showing a huge snowstorm (10-16") for the entire area all the way down to Wilmington to LBI, but less for far NWNJ, as it shifted south maybe 50 miles, and the 18Z NAM also shifting things south a ways and with less precip (8-11" for most of the state, while the 18Z RGEM had 6-10" for everywhere N of 276/195. So there was some movement south but not by all of them and precip amounts weren't as low as on the Euro/UK so who knows? The 18Z models at least make it clear that there likely won't be some huge shift south as some had discussed
Anyway, as expected, the NWS-Philly did increase snowfall amounts south of 78, but not as much as I thought they should and they now have warnings up for Poconos/Sussex for 8-13" of snow, for the Lehigh Valley, Morris, Warren for 7-10" of snow and for Berks, NW Bucks, Hunterdon and Somerset for 4-7" of snow and they have advisories up for Middlesex, Mercer, Lower Bucks and Montco for 3-5" of snow and for Western Monmouth and Chester for 2-4" of snow. IMO, all of those places under advisories should be under warnings for 4-7" of snow, especially given the southward shift we've seen from some of the models which brings more snow further south, which would also likely decrease snowfall amounts by a coupe of inches N of 80. In addition, given that about half the models have 3-6" or more of snow for Philly and SNJ (even at lower ratios), I would expect those areas to at least be under advisories for 2-4" of snow.
Also, the NWS-NYC now has warnings up for Union/Essex/Hudson and NYC/LI for 4-8", warnings up for LI for 5-10", warnings for eastern Passaic, eastern Bergen and Western Essex for 7-10" of snow and warnings for W. Passaic, W. Bergen and the Hudson Valley north of the Bronx for 9-13" of snow (and for CT for 7-12"). It's certainly going to be fun to see this all evolve and for the rain then snow to finally come late tonight with possibly hellacious snowfall rates of 1-2" per hour from 4 am to noon with a quick shut off after that. I still think TWC map is better than the one from the NWS, but we'll see soon.
Tomorrow morning's rush hour has the potential to be extremely difficult from at least 276/195 up through 84 for all of EPA/CNJ/NNJ/NYC/LI/SENY/CT with very heavy snow falling with 8-12" or more along and N of 78 and very possibly up to 8" down to 276/195 which would mean over 1" per hour rates for the 8-9 hours of the snow falling - and even for areas with warmer temps and less accumulation on roads, visibility will be very hindered and roads in some places could become difficult to travel on, especially near/N of 78 and as I've said before where we see >1" per hour rates even at 33-34F, untreated roads will become snow covered as those rates will exceed melting rates.
Lastly, don't forget that minor to moderate coastal flooding is likely for DE/NJ/NY coasts on Tuesday and 40-45 mph winds are likely for coastal areas and 30-35 mph inland as the storm cranks on Tuesday.
And don't forget to shovel before sunset and salt areas as needed, as temps will drop into the mid-20s. Also, be careful out there, but try to enjoy it if you can.
https://www.weather.gov/phi/
https://www.americanwx.com/bb/topic...winter-storm-6-12-for-many-on-feb-13/page/48/
IMO Craig Allen is the best met in the area...and is always my go to guy. His comments above pretty much indicate my gut feelings on the storm. My guess is no accumulation on pavement until after 8 AM but then ends up being a slushy mess on the roads...more on the grass but less than the 3-5" in the current forecast.
They need to reduce those numbers near 84 (NW Sussex and the Poconos) to maybe 4-8"; Lee Goldberg just did that and said the Catskills might not even get 2". Almost every model is showing the southward shift. This has kind of become an I-95 storm, which is why I also think the NWS is way under for areas S of 78 to 276/195, where I think 6-10" is looking likely (or at least 5-8" like TWC has) and where 8-12" is possible as it is for NYC/NENJ/LI and SW to Trenton. That's if we get the high rates of 1-2" per hr; if we get more like 1/2-1" per hour rates, we'll lose 25-30% to compaction and melting/ratios.
And the south move is also why I think 3-5" from Philly to Toms River and up to 276/195 makes more sense than the <1" the NWS has for most in that area. That area also has some chance of getting 5-8" as seen on some models.
If people along/near the NJ coast in Monmouth/northern Ocean end up getting 5-8" there are going to be a lot of surprised folks out there and I think that's probably a 50-50 shot (3-5" being 50/50 also). I'm betting we might see a correction this evening from the NWS as every 18Z model, except the RGEM has shown at least 8-12" (at 10:1 which would translate to 5-8" at lower ratios; the RGEM shows 5-8" at 10:1) for the shore.
Have always liked Craig - for years I used to email him occasionally with storm questions and he never hesitated to answer.
I like Craig Allen too but I've never seen/heard him that pissed before! You may do better with this thing up by you now - meaning less snow. Unless you want more snow. 😎
As could the NJ coast and parts of SNJ, as per my latest post - could be some surprised people tomorrow...
We see this every year almost - has there ever been a better case made for splitting Middlesex County in half? Surrounded on the west, north, and east by counties with warnings for 5-8/4-7" snowfall, yet northern Middlesex only has an advisory for 3-5" Nuts.
DT's update, from this morning where he made most of the changes to his forecast that I've been talking about since then also. Much better forecast, IMO.
This is his second last call map. He upped it from his earlier one today.
Wxrisk.com
This is a very dynamic and changing situation - a difficult forecast. Over the last 36 hours all of the models have come significantly further to the South with the track of the LOW which means that the heavy snow band which originally was supposed to be up in northeast PA / the Hudson Valley of New York/ and interior New England is now shifted to the south.
But the new afternoon data coming in here around 3pm -- shows that once again the European model is going to end up being correct. the 18z NAM and 18z HRRR - these are short range intermediate models that come out of 2-3PM have now dramatically cut their snow totals and have shoved the precipitation further to the South and show a much much weaker system.
If it sounds like I am uncertain it is because I am. And right now every single meteorologist in the NE usa is playing a game of WTF is going on? . NWS has a HUGE amounts of snow in southeast NY and southern New England as does Accuwx and TWC. We are all playing catch up to this constantly changing and weakening system. Normally when you get this closer to an event the models come to good agreement. Instead the data is going in all sorts of different directions only 18 hours before the event
Wxrisk.com
This is a very dynamic and changing situation - a difficult forecast. Over the last 36 hours all of the models have come significantly further to the South with the track of the LOW which means that the heavy snow band which originally was supposed to be up in northeast PA / the Hudson Valley of New York/ and interior New England is now shifted to the south.
But the new afternoon data coming in here around 3pm -- shows that once again the European model is going to end up being correct. the 18z NAM and 18z HRRR - these are short range intermediate models that come out of 2-3PM have now dramatically cut their snow totals and have shoved the precipitation further to the South and show a much much weaker system.
If it sounds like I am uncertain it is because I am. And right now every single meteorologist in the NE usa is playing a game of WTF is going on? . NWS has a HUGE amounts of snow in southeast NY and southern New England as does Accuwx and TWC. We are all playing catch up to this constantly changing and weakening system. Normally when you get this closer to an event the models come to good agreement. Instead the data is going in all sorts of different directions only 18 hours before the event
It's fascinating. Are the models having trouble with new data? Bad data? Trouble with transitioning to the low offshore? SSTs?
So it's already started raining in Philadelphia. A little early then expected.
The six o'clock run from 6ABC.
Rain Changes To Heavy, Wet Snow For A.M. Rush
6abc.com
The six o'clock run from 6ABC.
Rain Changes To Heavy, Wet Snow For A.M. Rush
AccuWeather: Rain tonight and some wet flakes Friday in the Philadelphia region
Heavy rain and gusty winds arrive tonight with a blast of much cooler air for the end of the week.
here was the clown kuchera for the 18z euro....some are certainly going to be disappointed. Will central jersey up along 78 to 95 be the sweet spot though
Not quite "model consensus" among the 18Z models (1 pm EST data inputs) about 10 hours before the start of the storm, but given the fragility of this setup which has been highlighted for almost a week now, it's not terrible either, as the models all had fairly similar tracks, but had major differences in the amount of precip and snowfall they produced, as the dynamics aloft were quite different (obviously). The hard part is figuring out what to do with the info.
These are all 10:1 ratio maps and Kuchera has been showing 6-7:1 ratios for areas south of 78, where the surface is warmer (and 10:1 N of 80, where temps are colder). The problem there is that if one took one of the snowy models, like the GFS or HRRR, we're talking 1.5" per hour for about the 8 hours of snow near 95 (about 4 am to noon) to get to ~12". At that kind of rate, crystal growth in the DGZ 15K feet up would be excellent giving >10:1 ratios in the column and melting would only be a minor issue as 1.5"/hr can easily overcome a melting rate in the neighborhood of 0.5"/hr at 34-35F surface temps (worst case), so ratios could easily be 8-9:1 even south of 78 (and when I posted that on the Discord site, 7 mets agreed). This could still put down maybe 10" out of the 12" that "falls" and likely lead to snowy roads (untreated ones at least).
But for the lowest snowfall model, the Euro, which only puts down maybe 5-7" between 195 and 80, that's only about 1/2-3/4" per hour rates and that likely means worse crystal growth aloft and more melting at 34-35F, so the Kuchera ratios around 6-7:1 would likely be good - it's a double whammy as less intensity means less snow falling and less snow accumulating. This might lead to only 3-5" on the ground and probably very little on paved surfaces.
And for the middle of the road models (RGEM/NAM) showing about 6-10" of 10:1 snow, maybe we'd have a compromise overall ratio of 7.5":1, leading to 4-7.5" in on the ground, which probably would still lead to at least snow covered local/untreated roads that aren't heavily traveled.
None of this tells me or anyone else what we're going to get - just thought it was an interesting exercise to see the impact of intensity on snow ratios. At this point, I'm a little worn out, but it's been fun to track this one. Time to start watching the radar and measuring/enjoying the snow (I hope).
These are all 10:1 ratio maps and Kuchera has been showing 6-7:1 ratios for areas south of 78, where the surface is warmer (and 10:1 N of 80, where temps are colder). The problem there is that if one took one of the snowy models, like the GFS or HRRR, we're talking 1.5" per hour for about the 8 hours of snow near 95 (about 4 am to noon) to get to ~12". At that kind of rate, crystal growth in the DGZ 15K feet up would be excellent giving >10:1 ratios in the column and melting would only be a minor issue as 1.5"/hr can easily overcome a melting rate in the neighborhood of 0.5"/hr at 34-35F surface temps (worst case), so ratios could easily be 8-9:1 even south of 78 (and when I posted that on the Discord site, 7 mets agreed). This could still put down maybe 10" out of the 12" that "falls" and likely lead to snowy roads (untreated ones at least).
But for the lowest snowfall model, the Euro, which only puts down maybe 5-7" between 195 and 80, that's only about 1/2-3/4" per hour rates and that likely means worse crystal growth aloft and more melting at 34-35F, so the Kuchera ratios around 6-7:1 would likely be good - it's a double whammy as less intensity means less snow falling and less snow accumulating. This might lead to only 3-5" on the ground and probably very little on paved surfaces.
And for the middle of the road models (RGEM/NAM) showing about 6-10" of 10:1 snow, maybe we'd have a compromise overall ratio of 7.5":1, leading to 4-7.5" in on the ground, which probably would still lead to at least snow covered local/untreated roads that aren't heavily traveled.
None of this tells me or anyone else what we're going to get - just thought it was an interesting exercise to see the impact of intensity on snow ratios. At this point, I'm a little worn out, but it's been fun to track this one. Time to start watching the radar and measuring/enjoying the snow (I hope).
14.4" in Philadelphia 🤣Not quite "model consensus" among the 18Z models (1 pm EST data inputs) about 10 hours before the start of the storm, but given the fragility of this setup which has been highlighted for almost a week now, it's not terrible either, as the models all had fairly similar tracks, but had major differences in the amount of precip and snowfall they produced, as the dynamics aloft were quite different (obviously). The hard part is figuring out what to do with the info.
These are all 10:1 ratio maps and Kuchera has been showing 6-7:1 ratios for areas south of 78, where the surface is warmer (and 10:1 N of 80, where temps are colder). The problem there is that if one took one of the snowy models, like the GFS or HRRR, we're talking 1.5" per hour for about the 8 hours of snow near 95 (about 4 am to noon) to get to ~12". At that kind of rate, crystal growth in the DGZ 15K feet up would be excellent giving >10:1 ratios in the column and melting would only be a minor issue as 1.5"/hr can easily overcome a melting rate in the neighborhood of 0.5"/hr at 34-35F surface temps (worst case), so ratios could easily be 8-9:1 even south of 78 (and when I posted that on the Discord site, 7 mets agreed). This could still put down maybe 10" out of the 12" that "falls" and likely lead to snowy roads (untreated ones at least).
But for the lowest snowfall model, the Euro, which only puts down maybe 5-7" between 195 and 80, that's only about 1/2-3/4" per hour rates and that likely means worse crystal growth aloft and more melting at 34-35F, so the Kuchera ratios around 6-7:1 would likely be good - it's a double whammy as less intensity means less snow falling and less snow accumulating. This might lead to only 3-5" on the ground and probably very little on paved surfaces.
And for the middle of the road models (RGEM/NAM) showing about 6-10" of 10:1 snow, maybe we'd have a compromise overall ratio of 7.5":1, leading to 4-7.5" in on the ground, which probably would still lead to at least snow covered local/untreated roads that aren't heavily traveled.
None of this tells me or anyone else what we're going to get - just thought it was an interesting exercise to see the impact of intensity on snow ratios. At this point, I'm a little worn out, but it's been fun to track this one. Time to start watching the radar and measuring/enjoying the snow (I hope).
