OT: Major Winter Storm 3/13-14 (Mixed Bag/High Uncertainty) and 3/10-11 (over)
- Thread starter RU848789
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I still tend to give the 0z and 12z runs more weight than a 6z or 18z, but I'm an old curmudgeon who learned it from even more curmudgeonly old farts.
For years that was supposedly the case due to differing data input and assimilation algorithms for the 6Z/18Z runs, but I recall a few years back reading that that was no longer the case and the forecast skill of the 4 daily runs are essentially identical.
The worst of it will likely be from about 10 pm to 5 am, roughly, although I doubt NYC or the urban corridor will see any accumulation on paved surfaces, so the only issue might be visibility if driving in falling snow - unless you're driving to some NW suburb of NYC where roads might be slick.
Often areas located on sandy soils, like Millville (or towns in the Pine Barrens, which Millville is on the edge of), are able to cool down at night, due to radiational cooling, which is more efficient over sandy soils (they drain well, leaving less water, which can act to trap heat). So on clear, fairly calm nights Millville would be likely to be colder than most locations. In addition, being far enough from the Delaware Bay to not be cooled down by the water, but in the far southern part of NJ, so likely warmer than most other locations to the north, I could see Millville often being a warm spot.
Interesting situation, as all of the models are showing 1-2" along the 95 corridor from Wilmington to NYC (except the UK which only shows snow N of 78), but the NWS is forecasting essentially nothing for 95. Very surprised with the NWS forecast being so conservative, especially with the NYC media also predicting 1-2" along 95 from CNJ to NYC. I know conditions will be marginal (temps in the 34-35F range) late Friday into early Saturday, when most of the precip will fall, possibly limiting accumulations, but all of the precip will fall while dark, eliminating sun angle as an issue.
It's not so much that I think their forecast is "wrong" but that they're going that strongly against the models (not that 1-2" overnight, melting by 10 am would be a big deal anyway - it's just surprising). Their map looks just like the NBM map and I also can't figure out how a blend of the models would show nearly nothing along 95, when most of the models are showing at least 1" and up to 2" for some. In addition, they're only showing maybe 1" along/N of 78 and 1-3" along and N of 80, where the models are showing 2-3 along 78 and 3-5" along/N of 80 (I included the 12Z Euro as an example - the GFS/CMC/NAM and RGEM are all fairly similar to this and the Euro nailed the minor/moderate snowfall on Mon/Tues). I guess we'll find out soon.
Lastly the models are still way all over the place for the Mon/Tues system, with the Euro showing a significant to major snowstorm just NW of 95 (with some snow along 95), the GFS showing a minor snowfall for most, the CMC showing a moderate snowstorm just NW of 95 with mostly rain along/SE of 95 and the UK showing a rainstorm for everyone in NJ except NW Sussex County. Still 5+ days out on that one, so uncertainty/variability is to be expected. It's worth noting that over the next ~10 days, areas not too far NW of 95 and N of 80 could be seeing major snowfall amounts (>8"), while there might be very little along/SE of 95 - that's March climatology for you...
Summary: The 3/10-11 system looks like some rain, Friday evening, followed by a few inches of snow from 195 to 78 and several inches of snow early Saturday along/N of 78 – not really a big deal, esp south of 78 where temps will be above 32F, limiting accumulation on roads. The 3/13-14 system looks like a much more powerful winter storm that could bring big rain, big snow (esp N of 78), or a big mix (even the 95 corridor could see several inches of snow and 1-2” of rain), although it’s possible the storm doesn’t undergo bombogenesis until it’s a little north of our area, sparing our area much of the heavy precip.
3/10-11 Storm: More curveballs in tonight's 0Z guidance. We're now about 48 hours from the event starting early Friday evening (vs. the 7 pm EST data inputs to the 0Z models) and while the models are fairly well aligned in the big picture, the fine details are significantly different for some locations, especially along and SE of 95 (and esp S of 195), where surface temps may never get below 35F, but snow will still be falling (after a few hours of rain), such that the question is how much of that snow will accumulate.
For example, take NB: if the NWS or a model forecasts 1" for NB at ~35F, but the actual temp is more like 36F, it's likely there would be no accumulation, but if the actual temp was 34F, it's likely there would be 2-3" of accumulation, since we'll all be getting 1/2-3/4" of total precip (liquid equivalent, which is 5-7.5" if it were all snow at 10:1 ratios) from the storm. That makes it very hard to predict snowfall and makes it very likely we'll see significant busts either high or low.
Anyway, let's get to the model discussion, noting that snowfall amounts assume a 10:1 ratio, which is probably not a great assumption, at least along and SE of 95, given temps in the mid-30s - snowfall amounts could end up being 1/2-2/3 of what's modeled. I also have a very hard time believing we're going to see much accumulation south of 195 and close to the coast (unless we get pretty heavy rates, which are a bit more likely close to the coast as the storm winds up). It's also hard to believe we'll see snow accumulating on roads along and SE of 95, but we could see roads covered along/N of 78
- The Euro shows a couple of inches from 195 up to 78 and several inches north of 78.
- The GFS is now the snowy outlier with 3-6" between 195 and 78 and 6-8" north of 78 and even a few inches down to Philly to Toms River, as it has a lot more precip/snow, especially from 4-9 am Sat, as it is showing a stronger secondary coastal low than the other models (or vs. what it has been showing for days).
- The CMC is somewhat similar to the GFS with 2-5" between 195 and 78 and a bit more N of 78, but only an inch or so south of 195.
- The UK is the wet outlier with 1/2-3/4" of almost all rain for everyone south of 78, with 1-2" of snow between 78 and 80 (and west of 287), and 2-4" N of 80.
- The NAM is similar to the CMC with 2-4" between 195 and 78 and a bit more N of 78, but only an inch or so south of 195 and up to 2" in spots that get heavy bands
- The RGEM has roughly 1-3" between 195 and 78 and 3-5" N of 78 (and esp west of 287), with <1" south of 195.
3/13-14 Storm: Looking ahead, the 3/13-14 event is 4.5-5 days away and, as usual, we have very little consensus, although every model, is showing a much more powerful storm than on Saturday (although the GFS doesn't have it strengthening until it reaches New England). And even where the storm is mostly rain, 1-2” of rain (or more) could lead to flooding, given wet antecedent conditions, and a powerful nor’easter usually would bring the potential for coastal flooding and high winds.
The Euro has a huge snowstorm north of 80 (1-2 feet of snow) and a huge rainstorm SE of 95 (2-3" of rain) and a lot of snow and rain in between on Mon/Tues. The GFS has 1-2" just NW of 95 (with 1/2" of rain for the rest of us), but has several inches N of 80 and a major snowstorm for much of New England, while the CMC also has 1-2" just NW of 95 (and 1"+ of rain along/SE of 95) and 3-6" N of 80, but misses most of New England, and the UK has a few inches NW of 95 (and rain along/SE of 95) on Monday, but has a significant snowstorm for most of us (and 1" or more of rain along/SE of 95) from the coastal low on Tuesday (and a major storm for most of New England). More to track.
https://www.pivotalweather.com/model.php
https://www.weather.gov/phi/
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I can't believe a professional meteorologist put a map like this out, with such a major discontinuity in it. One can't have a 0-1" swath next to a 3-6" swath, jumping magically from 1" to 3" by moving across that border - it needs at least a thin 1-3" swath between them to eliminate the discontinuity.Dan Zarrow 101.5
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Brief update, as I'm still in RU hoops heaven, lol.
Well, the Euro and CMC backed off snowfall south of 78 (and especially down towards 195/the coast), but the GFS and NAM showed even more snow for the 95 corridor and the coast (UK is still largely a miss with mostly rain, except well NW), so who knows. At this point, many of us in CNJ, especially along/near 95 could get anything from 1" or less to 5-6", lol. It's that big of a difference. N of 78 should get 2-4" almost no matter what, which is why advisories are up Somerset, Hunterdon, Warren, Sussex and the Lehigh Valley/Poconos (not yet for NE NJ or the Hudson Valley, but likely there too). The NWS-Philly did just update their snowfall map, extending the <1" area down to 195 and beefing up snowfall for CNJ and especially along N of 78, as I thought they'd do this morning, but didn't.
But the bigger news is that both the Euro and UK (the two best models) are showing a major snowstorm for almost all of us (except maybe SW of Philly to Toms River), as the coastal explodes from Mon night through Tues evening, while the GFS and CMC show just a minor snowfall on Monday for many, especially NW areas, with the storm exploding further NE and dumping only on New England. We're now only 4 days out, so need to get some clarity on this. Might just combine both storms in this thread, for continuity.
Edit: just added the NWS-NYC map, which was also adjusted upwards significantly, as expected...
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Sorry @e5fdny - with RU winning and other things going on, I just don't feel like separate threads, especially since the outcome of the first storm will affect the second, which is potentially a much bigger, more impactful storm (but also has a chance of a whiff, which tomorrow's "low ceiling" event doesn't really).
NWS-Philly Advisories are still up for Somerset/Hunterdon and the Lehigh Valley for 2-4" of snow Fri night/Sat morning and for 3-5" for Warren/Morris/Sussex and the Poconos) and they've been added by the NWS-NYC for Western Essex, Bergen, Passaic and the Hudson Valley north of the Tappan Zee (and CT) for 3-6" of snow.
Will be interesting to see if advisories go up for the next tier of counties to the south, i.e., Bucks/Montco, Mercer, Middlesex and NYC/LI, where only about an inch or so is forecast, but the potential is there for more, as per some of the models. Still not a major storm, but could be impactful, especially along/N of 78 where temps should drop to just below freezing (30-31F), whereas temps south of there look to fall to 32-33F (which is a little lower than previously forecast).
Will be interesting to see if advisories go up for the next tier of counties to the south, i.e., Bucks/Montco, Mercer, Middlesex and NYC/LI, where only about an inch or so is forecast, but the potential is there for more, as per some of the models. Still not a major storm, but could be impactful, especially along/N of 78 where temps should drop to just below freezing (30-31F), whereas temps south of there look to fall to 32-33F (which is a little lower than previously forecast).
🤷♂️🤷♂️ 🤷♂️
Seaside Heights St. Patrick's Day Parade postponed due to stormy forecast
The Ocean County St. Patrick's Day parade has been rescheduled for April 1 due to a stormy forecast for Saturday.
www.app.com
"The average of three inches this winter was more than 17 inches below normal. It is the second-lowest total on record since the winter of 1918-1919."
"Meteorologists observe winter from Dec. 1 through Feb. 28."
"Meteorologists observe winter from Dec. 1 through Feb. 28."
NJ had record high temperatures, low snowfall this winter. What's ahead for spring?
It was an unusual winter, with January being the warmest of the three months, and very little snow. What could that mean for the spring?
www.app.com
Brief update, as I'm still in RU hoops heaven, lol.
Well, the Euro and CMC backed off snowfall south of 78 (and especially down towards 195/the coast), but the GFS and NAM showed even more snow for the 95 corridor and the coast (UK is still largely a miss with mostly rain, except well NW), so who knows. At this point, many of us in CNJ, especially along/near 95 could get anything from 1" or less to 5-6", lol. It's that big of a difference. N of 78 should get 2-4" almost no matter what, which is why advisories are up Somerset, Hunterdon, Warren, Sussex and the Lehigh Valley/Poconos (not yet for NE NJ or the Hudson Valley, but likely there too). The NWS-Philly did just update their snowfall map, extending the <1" area down to 195 and beefing up snowfall for CNJ and especially along N of 78, as I thought they'd do this morning, but didn't.
But the bigger news is that both the Euro and UK (the two best models) are showing a major snowstorm for almost all of us (except maybe SW of Philly to Toms River), as the coastal explodes from Mon night through Tues evening, while the GFS and CMC show just a minor snowfall on Monday for many, especially NW areas, with the storm exploding further NE and dumping only on New England. We're now only 4 days out, so need to get some clarity on this. Might just combine both storms in this thread, for continuity.
Edit: just added the NWS-NYC map, which was also adjusted upwards significantly, as expected...
3/10-11 Storm: Today's 0Z models trended a bit warmer, wetter and less snowy, with the 0Z NAM, HRRR, and RGEM getting wetter for anyone south of 78 and along/SE of 95 (which is where the CMC/UK already were and stayed at 0Z), while the GFS held serve (relative to previous runs) with a fairly snowy solution with even a couple of inches down to 195; the Euro was in-between these camps. The NWS and most forecasters typically don't like to change forecasts too quickly, however, so I don't know if we'll see much change with the NWS 4 am forecast update - but could see them cutting back a little.
As I've said a few times, this is such a borderline event right on the edge between mostly rain and mostly snow for the 95 corridor, the coast and S of 78, meaning it would not surprise me to see <1" in NB or up to 5" in NB, for example. - with the <1" scenario looking more likely right now Hopefully we have closer to a consensus by tomorrow's 12Z runs. For folks along and N of 78, this looks like a solid 2-3"+ event, while for folks along and N of 80, 4+" seem pretty likely.
If you want to see the model outputs, they're in the AmericanWx thread, linked below...
https://www.americanwx.com/bb/topic/58986-march-11th-storm-threat/page/5/
3/13-14 Storm: This is the potential monster storm (on the 30th anniversary of the March 93 Superstorm), which could also be a whiff. So much depends on how the current storm evolves and on how, when, and if the northern and southern stream disturbances "phase" to produce an explosive winter storm Monday afternoon through Tuesday. The UK and the Euro still have this happening off the DelMarVa, pounding almost the entire area (SW of a Philly to Toms River line could easily see mostly rain though) with more than 10" of snow (with 20+" in spots) and probably also some heavy rain early in the storm, especially along/SE of 95. Both models show 2-3" of total liquid equivalent precip, so if things trend warmer we'd likely see some flooding.
The CMC moved significantly towards the UK/Euro solution, although it has the major snow further NE of those 2 models, i.e., along and N of 78 (with significant snow still shown down to 195), while the GFS still is showing not much precip/snow for our area (just a few inches of snow NW of 95 and maybe 0.5" of rain elsewhere), with the storm not bombing out until it gets near New England which gets hammered. Still 3-4 days out (since the more aggressive models are showing the main precip from Mon night to Tues night). So much uncertainty, but potentially a very high impact winter storm - beyond the precip there would also likely be some coastal flooding and high winds near the coast.
If you want to see the model outputs, they're in the AmericanWx thread, linked below. Also, if the worst outcome is realized, this could throw a major monkey wrench in car and air travel into Wednesday (NCAAs start Thursday).
https://www.americanwx.com/bb/topic/58993-march-13-14th-noreaster-threat/page/5/#comments
While meteorological winter may be Dec/Jan/Feb, for the purposes of winter snowfall, the season is from Oct through April (technically July thru June), so the least snowy winter in NYC still remains 2.8" in 72-73. Nobody looks at D/J/F snowfall as a full winter, especially since March is as snowy as Dec."The average of three inches this winter was more than 17 inches below normal. It is the second-lowest total on record since the winter of 1918-1919."
"Meteorologists observe winter from Dec. 1 through Feb. 28."
NJ had record high temperatures, low snowfall this winter. What's ahead for spring?
It was an unusual winter, with January being the warmest of the three months, and very little snow. What could that mean for the spring?www.app.com
so rain in NJ with limited, if any snowfall for Monmouth cnty? so no baseball tournaments will be played with weekend as the rain starts Friday and continues into Saturday evening
unless I'm wrong lol
No, precip should be done by Saturday morning (9-11 am) for Monmouth and I doubt Monmouth locations get more than 1" and might get nada (and 1" would be gone by noon). When I was a kid, that would mean we'd be playing baseball, lol.
Well, the NWS-Philly cut back fairly significantly on snowfall forecasts along/south of 78, even dropping the advisories for the Lehigh Valley, Hunterdon and Somerset counties, decreasing their snowfall forecasts from 2-3" to about 1" and areas south of there to <1". So, unless we see some decent changes back towards more snow for areas along/S of 78, this will now very likely be a non-event for most of CNJ. It is worth noting, however that the 6Z GFS and Euro still show 1-2" for most of CNJ, while the rest of the models show <1" or nada, so the threat isn't 100% dead for CNJ.
Advisories are still up for Morris/Warren/Sussex and the Poconos for 3-5" (but really only 1-2" is forecast for southern parts of Warren/Morris; and Monroe in the Poconos has a warning for 6-8"), while the NWS-NYC retained their advisories for western Essex, Bergen, Passaic and the Hudson Valley N of the Tappan Zee for 3-5".
No real update on the Mon/Tues event - waiting on the 12Z global model runs...
Well considering it was rescheduled for April 1st, I thought they were kidding.
Both upcoming storms trending toward all rain south of I-78. Models have had significant trouble handling the surface easterly flow in these events. 850mb freezing line and 540 thickness are WELL south of here and would suggest snow, but the easterly fetch at the 1000mb kills everything and keeps temps in the mid-40s. Don't be duped by model output showing 1-3" for Hunterdon, Somerset and Mercer. Seems like Mt. Holly has finally come around to this (which has affected other storms this year) and retracted the WWAs.
Agree on storm 1 being mostly rain south of 78 and have always been skeptical of the models showing more snow earlier in the week with such marginal temps.
But I disagree somewhat on storm 2, which all 4 global models now show as a phased capture scenario with a low bombing out bringing the chance for substantial snow at least along/N of 80 (every model has 6"+ N of 80 and 12"+ N of 84) and possibly along/N of 78 (and a shot at several inches down to 195, after some heavy rain). All depends on whether the storm is strong enough to get the cold conveyor belt going, which can bring heavy snow, even with surface temps in the mid-30s. Based on your comments, you know what you're talking about and have seen the models for Mon/Tues converging towards a powerful winter storm (they were much more all over the map until today). So much energy/potential, but so much volatility in outcomes being highly variable based on small upstream changes. Very tough to forecast.
Well, the NWS-Philly cut back fairly significantly on snowfall forecasts along/south of 78, even dropping the advisories for the Lehigh Valley, Hunterdon and Somerset counties, decreasing their snowfall forecasts from 2-3" to about 1" and areas south of there to <1". So, unless we see some decent changes back towards more snow for areas along/S of 78, this will now very likely be a non-event for most of CNJ. It is worth noting, however that the 6Z GFS and Euro still show 1-2" for most of CNJ, while the rest of the models show <1" or nada, so the threat isn't 100% dead for CNJ.
Advisories are still up for Morris/Warren/Sussex and the Poconos for 3-5" (but really only 1-2" is forecast for southern parts of Warren/Morris; and Monroe in the Poconos has a warning for 6-8"), while the NWS-NYC retained their advisories for western Essex, Bergen, Passaic and the Hudson Valley N of the Tappan Zee for 3-5".
No real update on the Mon/Tues event - waiting on the 12Z global model runs...
3/10-11 Storm: Not much change from this morning, as the 12Z models that just came out don’t show any move towards more snow along or south of 78, as all of the models except one currently show 1-2” along 78 and generally <1” south of there (the exception is the GFS which still shows several inches along 78 and 1-2” down to 195, but it’s an outlier).
So advisories (counties in blue below) only remain up for Morris/Warren/Sussex, Northampton and the Poconos for 3-5" (but really only 1-2" is forecast for southern parts of Warren/Morris; and Monroe in the Poconos has a warning for 6-8"), while the NWS-NYC retained their advisories for western Essex, Bergen, Passaic and the Hudson Valley N of the Tappan Zee for 3-5” of snow. So, unless we see some unexpected, last minute changes back towards more snow for areas along/S of 78, this will now very likely be a non-event for everyone south of 78, including most of NYC (except maybe the northern 1/3 of the City).
Rain will likely begin for most by 6 pm with a changeover to snow in the late evening Friday to early morning Saturday for areas under the advisories. The chance for snow along/south of 78 will come after 2-3 am through 8-9 am. It’s quite possible many of these areas see “white rain” for several hours, i.e., snow falling at 34-36F and just melting on contact, unless rates get high, which is unlikely.
https://www.weather.gov/phi/
https://www.americanwx.com/bb/topic/58986-march-11th-storm-threat/page/8/
3/13-14 Storm: Well we still have a potential major winter storm with heavy rain, then maybe heavy snow and a mix at times for areas along/N of 78, with more snow vs. rain north of there and less south of there. It's possible the 95 corridor, especially north of 276/195 (south of there will struggle to see much snow in any scenario, as it’ll likely be too warm) through NYC could see some heavy snow after a lot of heavy rain, but this area could also see almost all rain. The models are now in much better agreement on a coastal low forming near the OBX (as the initial low approaching from the Ohio Valley fades away) and coming up the coast and phasing with some northern stream upper level energy to cause the low to “bomb out” off the coast, but the finer details have major differences in system evolution and outcomes.
Right now it looks like a monster snowstorm (12" possible and 24" on the table) is likely anywhere north of I-84, through much of New England/NY and a major snowstorm along/north of I-80 (8-12”+ after some rain), but very hard to say how much snow vs. rain south of 80 and especially south of 78. The gradient could easily go from 10” along 80 to 4” along 78 to nada along 276/195, with 1-2” of rain falling in places with little to no snow, as temps might be just a few degrees too warm for snow, unless the storm gets really strong and pulls down cold air, via the cold conveyor belt (CCB), turning the rain to snow, which we’ve seen in past storms many times. Since we’re still 3+ days out (the main event is likely to be from Monday afternoon through most of Tuesday), a lot can change and many outcomes are still on the table, so stay tuned. If we had more cold air in place, this kind of scenario would produce an historic snowstorm for all, but we don't.
https://www.americanwx.com/bb/topic/58993-march-13-14th-noreaster-threat/page/11/
By the way, the NWS-NYC had a fantastic discussion on Storm 2 meteorology and even though this is "old" (from this morning), its discussion of the synoptic evolution of the storm and the uncertainty over outcomes is superb...
https://forecast.weather.gov/produc...&format=CI&version=1&glossary=1&highlight=off
Weak high pressure and an upper-level ridge over the Northeast
Sunday night moves eastward as a digging trough and multiple
shortwaves approach from the west. A southern stream shortwave over
the Southeast US begins to interact with a northern stream shortwave
embedded in a digging trough over the Upper Midwest Sunday night and
into early Monday. At the surface, two centers of low pressure over
the Great Lakes and Southeast US interact. Guidance has indicated
that the southern stream shortwave produces a coastal low pressure
off of the Mid-Atlantic coast that may very quickly intensify as the
energy from the northern stream shortwave phases with it. The
coastal low then moves northeastward, likely passing over or south
of the area late Monday and into early Tuesday. While the
positioning of this system may end up tracking close to the 70W 40N
benchmark resulting in typically snowy scenarios, a lack of a strong
high pressure system to the north and antecedent cold air means that
much of the precipitation for this system, especially for the coast,
remains largely plain rain.
There remains ample uncertainty in the degree and timing of phasing,
as well as the ultimate tracking of the low, but thinking now is
that much of the area initially sees rain Monday night and into
Tuesday. As the low occludes and wraps up over coastal New England
into late Tuesday, the strong NW flow may allow cold enough air to
support a mix with and transition to snow on the backside of the
low. The low then spins over the Northeast through the day on
Wednesday before finally departing on Thursday. The rest of the week
looks to remain generally dry with another low pressure possibly
impact the area by the weekend.
Just Googled NWS with my Zip and RED winter storm watch has been removed
The NWS just took down the winter weather advisories for 3-5" of snow for Essex, southern Bergen and southern Westchester, which is not a surprise given they scaled back accumulations in the map I posted, which shows they're all expecting 1-2" now (the map came out a couple of hours ago while the advisory change just happened).
