Winter weather to return

Sweet Pea's Corner

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Sep 10, 2001
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Since #'s is playing soccer or some other non weather posting activity I'll give a heads up for travelers.I see the rain we are getting Monday and Tuesday will turn to snow early Wednesday morning possibly accumulating to 2 inches. Then another storm will reach the region on Friday as freezing rain on Friday before turning to rain on Sat and Sun. Stay tuned as it's too early for details.
 

Tango Two

Heisman
Aug 21, 2001
58,332
37,403
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Tuesday
A chance of showers before 1pm, then rain likely after 1pm. Cloudy, with a high near 61. Southwest wind 10 to 15 mph. Chance of precipitation is 70%. New precipitation amounts of less than a tenth of an inch possible.

Tuesday Night
Rain before 2am, then rain and snow likely. Low around 33. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

Wednesday
A chance of snow, mixing with rain after 10am, then gradually ending. Partly sunny, with a high near 38. Chance of precipitation is 40%.

Wednesday Night
Mostly clear, with a low around 22.
 
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T2Kplus20

Heisman
May 1, 2007
31,919
19,876
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Tuesday
A chance of showers before 1pm, then rain likely after 1pm. Cloudy, with a high near 61. Southwest wind 10 to 15 mph. Chance of precipitation is 70%. New precipitation amounts of less than a tenth of an inch possible.

Tuesday Night
Rain before 2am, then rain and snow likely. Low around 33. Chance of precipitation is 80%. New precipitation amounts between a quarter and half of an inch possible.

Wednesday
A chance of snow, mixing with rain after 10am, then gradually ending. Partly sunny, with a high near 38. Chance of precipitation is 40%.

Wednesday Night
Mostly clear, with a low around 22.
Big temp drop.
 

RU848789

Heisman
Jul 27, 2001
65,219
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Since #'s is playing soccer or some other non weather posting activity I'll give a heads up for travelers.I see the rain we are getting Monday and Tuesday will turn to snow early Wednesday morning possibly accumulating to 2 inches. Then another storm will reach the region on Friday as freezing rain on Friday before turning to rain on Sat and Sun. Stay tuned as it's too early for details.
lol, retirement's killing me. Spent most of yesterday making a playlist for a local art opening party last night in Metuchen (my wife co-curates the Transformations Gallery in town), then was at the party until 9:30 pm, then drove down to AP to see the Ergs! one of the great unsung pop-punk bands from New Brunswick's basement scene in the early 2000s (with my son and about 6 of his friends - amazing show). And then soccer this morning and another DJ-ing performance this afternoon for the Metuchen Holiday House tour. So, have barely had time to look at this storm.

Anyway there is actually pretty good model consensus right now for a 2-4" snowfall from Philly-NYC, even down to the coast and including E PA and the Hudson Valley, with 3-6" on some models.

Having said that, setups like this are very tricky, as we need to rely on cold air filtering in behind a cold front before the precip from the low pressure system shuts off and. In addition, temps, at least for the 95 corridor and SE of there, are borderline for accumulating snow (32-34F), unless snowfall rates are at least moderate (possible), so this nowhere near a lock for accumulating snow at this point, which is why I think the NWS is underplaying this threat, as per their discussion below, which is reflected in their snowfall maps being a decent bit below what the models are showing.

On the plus side for snow, most of the snow should fall between about 1 am and 11 am on Wednesday after a fair amount of warmth and heavy rain on Tuesday. Lots to track over the next couple of days and preliminary NWS maps are below.

https://www.weather.gov/PHI

National Weather Service Mount Holly NJ
345 PM EST Sun Dec 8 2019

LONG TERM /TUESDAY THROUGH SUNDAY/...

Tuesday night and Wednesday...Still considerable uncertainty through
this period. The front should progress further off shore, but the
mid and upper level trough digs in closer to the region, so most
guidance depicts precipitation continuing overnight and through much
of the day on Wednesday. Without significant cyclogensis just off
shore, it would be difficult to get that much precipitation behind
the front in this kind of pattern as we should have persistent dry
air advection behind the front. If we do have precipitation into
Wednesday morning thanks to significant cold air advection we should
see precipitation change over to snow mostly north and west of the
fall line, and a rain/snow mix along the coastal plains. As
mentioned by the previous shift, even if it does happen, it will
likely be little more than a nuisance snow, with the possible
exception of northwest NJ and the southern Poconos which could see a
few inches of accumulation. Though snow totals did increase a bit,
this is not the result of major changes in the forecast, rather, the
forecast is now incorporating snow amounts during the day Wednesday
in addition to Tuesday night.




 

RU848789

Heisman
Jul 27, 2001
65,219
44,294
113
lol, retirement's killing me. Spent most of yesterday making a playlist for a local art opening party last night in Metuchen (my wife co-curates the Transformations Gallery in town), then was at the party until 9:30 pm, then drove down to AP to see the Ergs! one of the great unsung pop-punk bands from New Brunswick's basement scene in the early 2000s (with my son and about 6 of his friends - amazing show). And then soccer this morning and another DJ-ing performance this afternoon for the Metuchen Holiday House tour. So, have barely had time to look at this storm.

Anyway there is actually pretty good model consensus right now for a 2-4" snowfall from Philly-NYC, even down to the coast and including E PA and the Hudson Valley, with 3-6" on some models.

Having said that, setups like this are very tricky, as we need to rely on cold air filtering in behind a cold front before the precip from the low pressure system shuts off and. In addition, temps, at least for the 95 corridor and SE of there, are borderline for accumulating snow (32-34F), unless snowfall rates are at least moderate (possible), so this nowhere near a lock for accumulating snow at this point, which is why I think the NWS is underplaying this threat, as per their discussion below, which is reflected in their snowfall maps being a decent bit below what the models are showing.

On the plus side for snow, most of the snow should fall between about 1 am and 11 am on Wednesday after a fair amount of warmth and heavy rain on Tuesday. Lots to track over the next couple of days and preliminary NWS maps are below.

https://www.weather.gov/PHI

National Weather Service Mount Holly NJ
345 PM EST Sun Dec 8 2019

LONG TERM /TUESDAY THROUGH SUNDAY/...

Tuesday night and Wednesday...Still considerable uncertainty through
this period. The front should progress further off shore, but the
mid and upper level trough digs in closer to the region, so most
guidance depicts precipitation continuing overnight and through much
of the day on Wednesday. Without significant cyclogensis just off
shore, it would be difficult to get that much precipitation behind
the front in this kind of pattern as we should have persistent dry
air advection behind the front. If we do have precipitation into
Wednesday morning thanks to significant cold air advection we should
see precipitation change over to snow mostly north and west of the
fall line, and a rain/snow mix along the coastal plains. As
mentioned by the previous shift, even if it does happen, it will
likely be little more than a nuisance snow, with the possible
exception of northwest NJ and the southern Poconos which could see a
few inches of accumulation. Though snow totals did increase a bit,
this is not the result of major changes in the forecast, rather, the
forecast is now incorporating snow amounts during the day Wednesday
in addition to Tuesday night.





Not much change in the forecast from the NWS, who are calling for a general 1-3" snowfall early Wednesday. Some models, like the Euro/NAM are showing 1-3" and others, like the GFS, UK and CMC are showing 2-4" (with up to 6" in spots). I like the 1-3: call, given the warm/wet ground and borderline surface temps (33-34F) when the rain changes over to snow in the pre-dawn hours for most.

It'll probably take some time for the snow to accumulate at those conditions, as the melting rate will likely exceed the snowfall rate (unless the snow comes in heavy initially, which will overwhelm the melting rate quickly and once there's a 32F layer of snow on the ground, melting will be minimal after that). The other plus for snow is that much of the snow will fall before sunrise and even after that we have a very low sun angle this time of year.

Having said all that, the snowiest part of the day will likely be around the morning rush time, from 6-9 am, so there could be some impacts during that time, although snow will have an especially hard time accumulating on salted major roads.

Maps are below, but note that the NWS-Philly map is very likely off a bit, as it doesn't show the usual SE to NW increasing snowfall gradient, like the NWS-NYC map does, i.e., the amounts for NW NJ/E PA are low.



 

Tango Two

Heisman
Aug 21, 2001
58,332
37,403
78
Let's get to the real forecast. Army Navy Game in Philadelphia Saturday.


Friday Night
Rain likely, mainly after 1am. Cloudy, with a low around 39. Chance of precipitation is 60%.

Saturday
Rain likely. Cloudy, with a high near 56. Chance of precipitation is 60%.

Saturday Night
A chance of rain. Mostly cloudy, with a low around 41. Chance of precipitation is 50%.


https://forecast.weather.gov/MapClick.php?lat=39.95222000000007&lon=-75.16217999999998#.Xe6Q35NKjmE
 

RU848789

Heisman
Jul 27, 2001
65,219
44,294
113
FYI, that's outdated, 18-hour old info they posted yesterday evening. The NWS-Philly map this morning is wrong, as I posted above, but they haven't fixed them. The NWS-NYC map is correct. I suspect this morning's map had an error in the color - I think the 0.1-1" light blue in PA/NW NJ should be the 2-3" darker blue.
 
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RU848789

Heisman
Jul 27, 2001
65,219
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113
FYI, today's 12Z models are fairly similar to last night's. Euro/NAM with 1-3" area-wide and GFS/UK/CMC with a general 2-4" area-wide, which 48 hours out, is fairly good consensus. I'm on the 1-3" side, given the borderline temps and lack of confidence in enough precip being left after the changeover, but even 1-3" falling from the wee hours through 9-10 am could make for a difficult morning rush, especially for secondary roads (I'd expect most major highways to be ok - maybe a bit slushy, although visibility will be impacted). Let's see what the NWS says at 4 pm.
 

RU848789

Heisman
Jul 27, 2001
65,219
44,294
113
Doesn't it have to be winter for us to have winter weather. We have 2 weeks to go.
Meteorological winter starts on 12/1 for what it's worth (Dec/Jan/Feb are the 3 coldest months), although if it were done by the 91+ coldest days it would be about 12/7-3/8.
 

RU848789

Heisman
Jul 27, 2001
65,219
44,294
113
Let's get to the real forecast. Army Navy Game in Philadelphia Saturday.
Friday night into Saturday morning is going to be a soaker, but the rain for Philly is likely to be just about over by kickoff. Too early to tell, though, as 1 or 2 models have the precip exiting in the late afternoon, while most have it exiting the area by about noon (~6 hours difference is huge for fans, but a small variable 5+ days out in a forecast) - should have a better handle on timing by Weds/Thursday.
 

RUhobbit

Senior
Nov 18, 2002
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lol, retirement's killing me. Spent most of yesterday making a playlist for a local art opening party last night in Metuchen (my wife co-curates the Transformations Gallery in town), then was at the party until 9:30 pm, then drove down to AP to see the Ergs! one of the great unsung pop-punk bands from New Brunswick's basement scene in the early 2000s (with my son and about 6 of his friends - amazing show). And then soccer this morning and another DJ-ing performance this afternoon for the Metuchen Holiday House tour. So, have barely had time to look at this storm.

Anyway there is actually pretty good model consensus right now for a 2-4" snowfall from Philly-NYC, even down to the coast and including E PA and the Hudson Valley, with 3-6" on some models.

Having said that, setups like this are very tricky, as we need to rely on cold air filtering in behind a cold front before the precip from the low pressure system shuts off and. In addition, temps, at least for the 95 corridor and SE of there, are borderline for accumulating snow (32-34F), unless snowfall rates are at least moderate (possible), so this nowhere near a lock for accumulating snow at this point, which is why I think the NWS is underplaying this threat, as per their discussion below, which is reflected in their snowfall maps being a decent bit below what the models are showing.

On the plus side for snow, most of the snow should fall between about 1 am and 11 am on Wednesday after a fair amount of warmth and heavy rain on Tuesday. Lots to track over the next couple of days and preliminary NWS maps are below.

https://www.weather.gov/PHI

National Weather Service Mount Holly NJ
345 PM EST Sun Dec 8 2019

LONG TERM /TUESDAY THROUGH SUNDAY/...

Tuesday night and Wednesday...Still considerable uncertainty through
this period. The front should progress further off shore, but the
mid and upper level trough digs in closer to the region, so most
guidance depicts precipitation continuing overnight and through much
of the day on Wednesday. Without significant cyclogensis just off
shore, it would be difficult to get that much precipitation behind
the front in this kind of pattern as we should have persistent dry
air advection behind the front. If we do have precipitation into
Wednesday morning thanks to significant cold air advection we should
see precipitation change over to snow mostly north and west of the
fall line, and a rain/snow mix along the coastal plains. As
mentioned by the previous shift, even if it does happen, it will
likely be little more than a nuisance snow, with the possible
exception of northwest NJ and the southern Poconos which could see a
few inches of accumulation. Though snow totals did increase a bit,
this is not the result of major changes in the forecast, rather, the
forecast is now incorporating snow amounts during the day Wednesday
in addition to Tuesday night.




Small world re: Ergs! Mikey Erg is a childhood friend of mine. We reconnected recently and he’s still that great guy! I’ll pass along your compliments!
 
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JMORC2003

All-Conference
Dec 22, 2008
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lol, retirement's killing me. Spent most of yesterday making a playlist for a local art opening party last night in Metuchen (my wife co-curates the Transformations Gallery in town), then was at the party until 9:30 pm, then drove down to AP to see the Ergs! one of the great unsung pop-punk bands from New Brunswick's basement scene in the early 2000s (with my son and about 6 of his friends - amazing show). And then soccer this morning and another DJ-ing performance this afternoon for the Metuchen Holiday House tour. So, have barely had time to look at this storm.

Anyway there is actually pretty good model consensus right now for a 2-4" snowfall from Philly-NYC, even down to the coast and including E PA and the Hudson Valley, with 3-6" on some models.

Having said that, setups like this are very tricky, as we need to rely on cold air filtering in behind a cold front before the precip from the low pressure system shuts off and. In addition, temps, at least for the 95 corridor and SE of there, are borderline for accumulating snow (32-34F), unless snowfall rates are at least moderate (possible), so this nowhere near a lock for accumulating snow at this point, which is why I think the NWS is underplaying this threat, as per their discussion below, which is reflected in their snowfall maps being a decent bit below what the models are showing.

On the plus side for snow, most of the snow should fall between about 1 am and 11 am on Wednesday after a fair amount of warmth and heavy rain on Tuesday. Lots to track over the next couple of days and preliminary NWS maps are below.

https://www.weather.gov/PHI

National Weather Service Mount Holly NJ
345 PM EST Sun Dec 8 2019

LONG TERM /TUESDAY THROUGH SUNDAY/...

Tuesday night and Wednesday...Still considerable uncertainty through
this period. The front should progress further off shore, but the
mid and upper level trough digs in closer to the region, so most
guidance depicts precipitation continuing overnight and through much
of the day on Wednesday. Without significant cyclogensis just off
shore, it would be difficult to get that much precipitation behind
the front in this kind of pattern as we should have persistent dry
air advection behind the front. If we do have precipitation into
Wednesday morning thanks to significant cold air advection we should
see precipitation change over to snow mostly north and west of the
fall line, and a rain/snow mix along the coastal plains. As
mentioned by the previous shift, even if it does happen, it will
likely be little more than a nuisance snow, with the possible
exception of northwest NJ and the southern Poconos which could see a
few inches of accumulation. Though snow totals did increase a bit,
this is not the result of major changes in the forecast, rather, the
forecast is now incorporating snow amounts during the day Wednesday
in addition to Tuesday night.




Did the Ergs play with the original lineup?
 

RU848789

Heisman
Jul 27, 2001
65,219
44,294
113
Not much change in the forecast from the NWS, who are calling for a general 1-3" snowfall early Wednesday. Some models, like the Euro/NAM are showing 1-3" and others, like the GFS, UK and CMC are showing 2-4" (with up to 6" in spots). I like the 1-3: call, given the warm/wet ground and borderline surface temps (33-34F) when the rain changes over to snow in the pre-dawn hours for most.

It'll probably take some time for the snow to accumulate at those conditions, as the melting rate will likely exceed the snowfall rate (unless the snow comes in heavy initially, which will overwhelm the melting rate quickly and once there's a 32F layer of snow on the ground, melting will be minimal after that). The other plus for snow is that much of the snow will fall before sunrise and even after that we have a very low sun angle this time of year.

Having said all that, the snowiest part of the day will likely be around the morning rush time, from 6-9 am, so there could be some impacts during that time, although snow will have an especially hard time accumulating on salted major roads.

Maps are below, but note that the NWS-Philly map is very likely off a bit, as it doesn't show the usual SE to NW increasing snowfall gradient, like the NWS-NYC map does, i.e., the amounts for NW NJ/E PA are low.




NWS 4 pm update is basically status quo, i.e., a general 1-3" snowfall for most of the Philly-NJ-NYC area, including well N/W (where up to 4" may fall) and the coast (where only an inch or so may fall or less especially south of 195). Here's the updated NWS-Philly map, which has been corrected and the NWS-NYC map. This is not going to be a major, debilitating storm, but the morning rush hour timeframe (6-9 am) will be when the snow is likely to be heaviest and accumulating, even on paved surfaces (secondary roads, at least), especially before sunrise and even before 9 am with the very low sun angle, so there could be some travel impacts. I'd imagine all roads will be fine by late morning with temps going into the mid-upper 30s. Could be some black ice on Thursday, though, with temps plummeting well below 32F Wednesday night and struggling to reach 32F on Thursday.


 

RU848789

Heisman
Jul 27, 2001
65,219
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Small world re: Ergs! Mikey Erg is a childhood friend of mine. We reconnected recently and he’s still that great guy! I’ll pass along your compliments!

Did the Ergs play with the original lineup?
According to my son and his friends, who seemed to know every word of every song, yes it was the original lineup. I have both of their full albums, but only knew about 4-5 songs really well (not as much free time, lol). Definltely pass along the compliments of an aging punk rocker, lol - they really delivered an awesome set.

They played dorkrockcorkrod in its entirety and then played a ton of other songs, including a Hunchback cover and 2 Christmas songs (of theirs, I think) I'd never heard before, playing for about an hour and 45 minutes. House of Independents holds 500 for a sold out show and this sold out months ago and I'd swear at least half of the audience knew most of the words to every song - that's an extraordinarily loyal fanbase.

Was my first time seeing them live and same for our son, as they basically broke up and stopped touring around 2009 (my son was only 15). He and his friends (and I) all said it was one of the best shows they'd seen in the last few years. I still don't understand why they didn't become this generations version of the Ramones (everyone in the band took on the last name of Erg, like the Ramones did) - I think they're that good. Below is a pic from the show and two of my favorite songs for those who have no idea what they might have missed.





 
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Tango Two

Heisman
Aug 21, 2001
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US National Weather Service Philadelphia/Mount Holly
·
Good Afternoon! unsettled weather will continue for the next couple days with the biggest period of concern being Tuesday night into early Wednesday when there is an increasing likelihood for some accumulating snow to fall across parts of area.In the meantime, periods of rain mild temperatures continue through the day Tuesday

Tuesday night... temperatures will cool with rain changing to snow from northwest to southeast. The changeover should occur through the evening over the southern Poconos and NW New Jersey and reach the I-95 corridor around dawn Wednesday with rain changing to snow. Snow should continue for a few hours into Wednesday morning and may mix at times with rain before coming to an end by midday. In general, 1-2 inches of snow can be expected except less than an inch over most of the Delmarva and the immediate coast of New Jersey. Also, the Poconos and NW New Jersey look to see slightly higher amounts of 2-4 inches. The snow may impact Wednesday morning's commute with slippery road conditions and reduced visibilities.

Please continue to monitor the forecast for updates at weather.gov/phi. Confidence is high on the unsettled weather continuing to affect us through early Wednesday with an eventual change from rain to snow with colder temperatures but is low regarding the exact changeover times as well as specific snow amounts.
 

e5fdny

Heisman
Nov 11, 2002
114,450
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lol, retirement's killing me. Spent most of yesterday making a playlist for a local art opening party last night in Metuchen (my wife co-curates the Transformations Gallery in town), then was at the party until 9:30 pm, then drove down to AP to see the Ergs! one of the great unsung pop-punk bands from New Brunswick's basement scene in the early 2000s (with my son and about 6 of his friends - amazing show). And then soccer this morning and another DJ-ing performance this afternoon for the Metuchen Holiday House tour. So, have barely had time to look at this storm.

Anyway there is actually pretty good model consensus right now for a 2-4" snowfall from Philly-NYC, even down to the coast and including E PA and the Hudson Valley, with 3-6" on some models.

Having said that, setups like this are very tricky, as we need to rely on cold air filtering in behind a cold front before the precip from the low pressure system shuts off and. In addition, temps, at least for the 95 corridor and SE of there, are borderline for accumulating snow (32-34F), unless snowfall rates are at least moderate (possible), so this nowhere near a lock for accumulating snow at this point, which is why I think the NWS is underplaying this threat, as per their discussion below, which is reflected in their snowfall maps being a decent bit below what the models are showing.

On the plus side for snow, most of the snow should fall between about 1 am and 11 am on Wednesday after a fair amount of warmth and heavy rain on Tuesday. Lots to track over the next couple of days and preliminary NWS maps are below.

https://www.weather.gov/PHI

National Weather Service Mount Holly NJ
345 PM EST Sun Dec 8 2019

LONG TERM /TUESDAY THROUGH SUNDAY/...

Tuesday night and Wednesday...Still considerable uncertainty through
this period. The front should progress further off shore, but the
mid and upper level trough digs in closer to the region, so most
guidance depicts precipitation continuing overnight and through much
of the day on Wednesday. Without significant cyclogensis just off
shore, it would be difficult to get that much precipitation behind
the front in this kind of pattern as we should have persistent dry
air advection behind the front. If we do have precipitation into
Wednesday morning thanks to significant cold air advection we should
see precipitation change over to snow mostly north and west of the
fall line, and a rain/snow mix along the coastal plains. As
mentioned by the previous shift, even if it does happen, it will
likely be little more than a nuisance snow, with the possible
exception of northwest NJ and the southern Poconos which could see a
few inches of accumulation. Though snow totals did increase a bit,
this is not the result of major changes in the forecast, rather, the
forecast is now incorporating snow amounts during the day Wednesday
in addition to Tuesday night.




If you don’t start the next one I am coming to Metuchen and popping that soccer ball.
 
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JMORC2003

All-Conference
Dec 22, 2008
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According to my son and his friends, who seemed to know every word of every song, yes it was the original lineup. I have both of their full albums, but only knew about 4-5 songs really well (not as much free time, lol). Definltely pass along the compliments of an aging punk rocker, lol - they really delivered an awesome set.

They played dorkrockcorkrod in its entirety and then played a ton of other songs, including a Hunchback cover and 2 Christmas songs (of theirs, I think) I'd never heard before, playing for about an hour and 45 minutes. House of Independents holds 500 for a sold out show and this sold out months ago and I'd swear at least half of the audience knew most of the words to every song - that's an extraordinarily loyal fanbase.

Was my first time seeing them live and same for our son, as they basically broke up and stopped touring around 2009 (my son was only 15). He and his friends (and I) all said it was one of the best shows they'd seen in the last few years. I still don't understand why they didn't become this generations version of the Ramones (everyone in the band took on the last name of Erg, like the Ramones did) - I think they're that good. Below is a pic from the show and two of my favorite songs for those who have no idea what they might have missed.






I used to go see/know the guys from Dirt Bike Annie when Mikey Erg played drums for them. I thought he was nuts for quitting to fully concentrate on the ergs, dirt bike Annie was the best local nj/nyc band around at the time. I saw the Ergs a bunch of times early on playing with friends’ bands, then just stopped caring about the scene. A few years later I learn that they developed on of the most rabid and loyal fan bases around. They were certainly able to put it all together. Crazy.
 
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RU848789

Heisman
Jul 27, 2001
65,219
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If you don’t start the next one I am coming to Metuchen and popping that soccer ball.

lol, I think we can blame @mildone for this, since he's the one who invited me into their weekly soccer game - even if he's not actually at fault at all - it's just fun to blame him for stuff. Bastard.
 
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e5fdny

Heisman
Nov 11, 2002
114,450
53,606
102
lol, I think we can blame @mildone for this, since he's the one who invited me into their weekly soccer game - even if he's not actually at fault at all - it's just fun to blame him for stuff. Bastard.
But now you will have the time.

So get to it, Lloyd Lindsay Young! LOL

Hellllllooooooooo.....Metuchen!
 

RU848789

Heisman
Jul 27, 2001
65,219
44,294
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0Z models tonight held serve, i.e., Euro/NAM showing a general 1-2" with a few spots up to 3" (near the shore and on LI, due to more precip), while the GFS, Canadian and RGEM show 2-5" for the whole area (Philly-NJ-NYC). Going to need decent snowfall rates to accumulate on the warm/wet ground with air temps at 33-35F, although much of the modeled snow falls before 8 am, which counters the other variables a bit. Because of the borderline temps and the Euro, I like the 1-3" forecasts more than the 2-4" forecasts (not much difference, I know, but there is a difference) and I suspect the NWS won't make many changes in this morning's forecasts.
 

RU848789

Heisman
Jul 27, 2001
65,219
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NWS 4 pm update is basically status quo, i.e., a general 1-3" snowfall for most of the Philly-NJ-NYC area, including well N/W (where up to 4" may fall) and the coast (where only an inch or so may fall or less especially south of 195). Here's the updated NWS-Philly map, which has been corrected and the NWS-NYC map. This is not going to be a major, debilitating storm, but the morning rush hour timeframe (6-9 am) will be when the snow is likely to be heaviest and accumulating, even on paved surfaces (secondary roads, at least), especially before sunrise and even before 9 am with the very low sun angle, so there could be some travel impacts. I'd imagine all roads will be fine by late morning with temps going into the mid-upper 30s. Could be some black ice on Thursday, though, with temps plummeting well below 32F Wednesday night and struggling to reach 32F on Thursday.



Still looking pretty minor with both NWS offices in our area reducing the snowfall forecasts a bit vs. yesterday. The NWS-Philly is calling for 1-3" of snow N of 78 and maybe an inch or up to 2" between from 78 southward about 10-20 miles, with 1" or less south of that zone and not much at all south of 276/195 in PA/NJ. They did not post advisories, as they feel accumulations on the roads will be minimal with borderline temps (33-34F at the surface) and warm/wet surfaces before the changeover to snow in the wee hours of Wednesday morning.

The NWS-NYC is calling for a general 2" snowfall for NENJ, NYC Metro, LI and the lower Hudson Valley/CT. See the maps below. However, they have issued advisories, even for less than the usual amount (3" is the normal criterion for an advisory), since the snow will be falling and possibly accumulating from about 3 am through the morning rush hour.

Very tricky forecast, especially with some models still showing 2-4" along and mostly SE of the 95 corridor towards the coast, where the most precip is forecast and assuming enough cold air moves in with the approaching front to turn the rain into snow early enough to accumulate. I think the lower NWS amounts are more likely, though, given the above 32F surface temps and warm/wet ground - maybe there could be 2-4" on grassy surfaces/cartops, but very unlikely to get more than 1" or so on paved surfaces, especially for any treated/heavily traveled roads.

https://www.weather.gov/phi/




 

RU848789

Heisman
Jul 27, 2001
65,219
44,294
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Still looking pretty minor with both NWS offices in our area reducing the snowfall forecasts a bit vs. yesterday. The NWS-Philly is calling for 1-3" of snow N of 78 and maybe an inch or up to 2" between from 78 southward about 10-20 miles, with 1" or less south of that zone and not much at all south of 276/195 in PA/NJ. They did not post advisories, as they feel accumulations on the roads will be minimal with borderline temps (33-34F at the surface) and warm/wet surfaces before the changeover to snow in the wee hours of Wednesday morning.

The NWS-NYC is calling for a general 2" snowfall for NENJ, NYC Metro, LI and the lower Hudson Valley/CT. See the maps below. However, they have issued advisories, even for less than the usual amount (3" is the normal criterion for an advisory), since the snow will be falling and possibly accumulating from about 3 am through the morning rush hour.

Very tricky forecast, especially with some models still showing 2-4" along and mostly SE of the 95 corridor towards the coast, where the most precip is forecast and assuming enough cold air moves in with the approaching front to turn the rain into snow early enough to accumulate. I think the lower NWS amounts are more likely, though, given the above 32F surface temps and warm/wet ground - maybe there could be 2-4" on grassy surfaces/cartops, but very unlikely to get more than 1" or so on paved surfaces, especially for any treated/heavily traveled roads.

https://www.weather.gov/phi/





Been at our annual work holiday party since about 1 pm, DJ-ing it and eating and drinking copious amounts of stuff, so hadn't had a chance to check the weather until now. Being retired, but still getting to party with all my former coworkers doesn't suck.

Anyway, new snowfall maps are up and they're pretty similar to this morning's with 1-2" expected for most and with advisories only up for NE NJ/NYC/LI/HV from the NWS-NYC (no advisories in the NWS-Philly office's county area). As per before, some models are showing 2-4" of snow and others (including the Euro, still) are showing 1-2" of snow for most and most of the models are showing more precip and more snow along and SE of I-95 towards the shore, but not all are showing that and it'll be slightly warmer towards the shore, so uncertainty on snowfall amounts is greatest there. Also, as per below, most of the accumulation is expected on colder/grassy surfaces, not paved surfaces.

Predicting who might get 1" vs. 3" (in a few places) vs. near 0" is almost impossible right now, as the snowfall amounts will depend on snowfall rates vs. melting rates (on various surfaces, with temps around 33-34F when the changeover occurs), meaning significant melting will occur, especially where snowfall rates are light to moderate. This will be a nowcasting event for the most part.

One will need snowfall rates to exceed about 1/2" per hour to get decent accumulations going (and once a layer of snow is down it's at 32F, meaning the 32F falling snow will then have a much lower melting rate from the 33-34F air, i.e., maybe <1/8" per hour of melting). Also, with this storm, melting rates are greater for warmer paved surfaces, so this is likely to be a storm where snow primarily accumulates on grassy/colder surfaces with little on paved surfaces (unless there are surprisingly high rates in a few locations).

And predicting what locations will get snowfall rates high enough to get accumulating snow, especially on paved surfaces is very difficult, as areas of higher rates will be governed by mesoscale (on the order of tens of miles) processes for this storm, which are beyond the ability of our current models to discern well in advance. Anyway below are the latest maps from the NWS.



 

Knight Shift

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May 19, 2011
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Been at our annual work holiday party since about 1 pm, DJ-ing it and eating and drinking copious amounts of stuff, so hadn't had a chance to check the weather until now. Being retired, but still getting to party with all my former coworkers doesn't suck.

Anyway, new snowfall maps are up and they're pretty similar to this morning's with 1-2" expected for most and with advisories only up for NE NJ/NYC/LI/HV from the NWS-NYC (no advisories in the NWS-Philly office's county area). As per before, some models are showing 2-4" of snow and others (including the Euro, still) are showing 1-2" of snow for most and most of the models are showing more precip and more snow along and SE of I-95 towards the shore, but not all are showing that and it'll be slightly warmer towards the shore, so uncertainty on snowfall amounts is greatest there. Also, as per below, most of the accumulation is expected on colder/grassy surfaces, not paved surfaces.

Predicting who might get 1" vs. 3" (in a few places) vs. near 0" is almost impossible right now, as the snowfall amounts will depend on snowfall rates vs. melting rates (on various surfaces, with temps around 33-34F when the changeover occurs), meaning significant melting will occur, especially where snowfall rates are light to moderate. This will be a nowcasting event for the most part.

One will need snowfall rates to exceed about 1/2" per hour to get decent accumulations going (and once a layer of snow is down it's at 32F, meaning the 32F falling snow will then have a much lower melting rate from the 33-34F air, i.e., maybe <1/8" per hour of melting). Also, with this storm, melting rates are greater for warmer paved surfaces, so this is likely to be a storm where snow primarily accumulates on grassy/colder surfaces with little on paved surfaces (unless there are surprisingly high rates in a few locations).

And predicting what locations will get snowfall rates high enough to get accumulating snow, especially on paved surfaces is very difficult, as areas of higher rates will be governed by mesoscale (on the order of tens of miles) processes for this storm, which are beyond the ability of our current models to discern well in advance. Anyway below are the latest maps from the NWS.



This is the Mt Holly prediction for 08736--Wall/Manasquan--It was near 60 degrees late into this evening. The temperature is not predicted to drop below 33 Degrees. How can there be a snow accumulation prediction?

 

RU848789

Heisman
Jul 27, 2001
65,219
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This is the Mt Holly prediction for 08736--Wall/Manasquan--It was near 60 degrees late into this evening. The temperature is not predicted to drop below 33 Degrees. How can there be a snow accumulation prediction?


It would be easier to show in equations, but I doubt most people will get that, so here are a lot of words I just posted on FB on the NWS page in answer to the same question...

Yes, snow can accumulate with surface temps at 33-34F or even higher. The governing equation for snowfall accumulation is simple: if the snowfall rate (in inches per hour, e.g.) exceeds the melting rate (in inches per hour), then snow will accumulate. It's that simple. Now, determining the melting rate is not simple at all, as that's a function of the surface temp (which is different for paved surfaces vs. grassy/colder surfaces), which is influenced by the ground temp underneath, the air temp, the degree of indirect sunlight reaching the ground (during daylight), whether salt is present, etc.

Having said that, though, a good rule of thumb based on experience and crude calculations, is that one needs snowfall rates of 1/2"/hr or more when the surface temp is 33-34F and with a high sun angle (like in March), but only about 1/4" or so when it's 33-34F at the surface at night. Keep in mind that even if the surface temp is 50F 8 hours before snow starts, the falling/melting snow will cool the surface down quickly into the mid-30s as energy is transferred from the warm ground to the snow to effect melting (which requires energy input).

Finally, one very important factor in any borderline situation, like this one. If the snowfall rate becomes heavy (like 1" per hour rates), the snow will accumulate in broad daylight at 35F in April, let alone at night at 34F in December. And once a layer of snow is established on the ground, that snow is, by definition, at 32F, meaning subsequent snow that falls will no longer melt at anywhere near the rate it would on bare ground, as one has 32F snow falling on 32F snow on the ground. So if a foothold can be gained where snow accumulates, subsequent snow that falls will only be subject to melting from the 33-34F air temp, which would only lead to melting rates in the 1/8" per hour range. Hope that helps.
 
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e5fdny

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Nov 11, 2002
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It would be easier to show in equations, but I doubt most people will get that, so here are a lot of words I just posted on FB on the NWS page in answer to the same question...

Yes, snow can accumulate with surface temps at 33-34F or even higher. The governing equation for snowfall accumulation is simple: if the snowfall rate (in inches per hour, e.g.) exceeds the melting rate (in inches per hour), then snow will accumulate. It's that simple. Now, determining the melting rate is not simple at all, as that's a function of the surface temp (which is different for paved surfaces vs. grassy/colder surfaces), which is influenced by the ground temp underneath, the air temp, the degree of indirect sunlight reaching the ground (during daylight), whether salt is present, etc.

Having said that, though, a good rule of thumb based on experience and crude calculations, is that one needs snowfall rates of 1/2"/hr or more when the surface temp is 33-34F and with a high sun angle (like in March), but only about 1/4" or so when it's 33-34F at the surface at night. Keep in mind that even if the surface temp is 50F 8 hours before snow starts, the falling/melting snow will cool the surface down quickly into the mid-30s as energy is transferred from the warm ground to the snow to effect melting (which requires energy input).

Finally, one very important factor in any borderline situation, like this one. If the snowfall rate becomes heavy (like 1" per hour rates), the snow will accumulate in broad daylight at 35F in April, let alone at night at 34F in December. And once a layer of snow is established on the ground, that snow is, by definition, at 32F, meaning subsequent snow that falls will no longer melt at anywhere near the rate it would on bare ground, as one has 32F snow falling on 32F snow on the ground. So if a foothold can be gained where snow accumulates, subsequent snow that falls will only be subject to melting from the 33-34F air temp, which would only lead to melting rates in the 1/8" per hour range. Hope that helps.
That's what you do...help.

Much appreciated as always.
 

newell138

Heisman
Aug 1, 2001
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sleet and icy mix down here in Ocean City. Always love a Wednesday snow since thats the one day I have to drive into the office, it gives me an excuse to not drive in.
 

RU848789

Heisman
Jul 27, 2001
65,219
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Been at our annual work holiday party since about 1 pm, DJ-ing it and eating and drinking copious amounts of stuff, so hadn't had a chance to check the weather until now. Being retired, but still getting to party with all my former coworkers doesn't suck.

Anyway, new snowfall maps are up and they're pretty similar to this morning's with 1-2" expected for most and with advisories only up for NE NJ/NYC/LI/HV from the NWS-NYC (no advisories in the NWS-Philly office's county area). As per before, some models are showing 2-4" of snow and others (including the Euro, still) are showing 1-2" of snow for most and most of the models are showing more precip and more snow along and SE of I-95 towards the shore, but not all are showing that and it'll be slightly warmer towards the shore, so uncertainty on snowfall amounts is greatest there. Also, as per below, most of the accumulation is expected on colder/grassy surfaces, not paved surfaces.

Predicting who might get 1" vs. 3" (in a few places) vs. near 0" is almost impossible right now, as the snowfall amounts will depend on snowfall rates vs. melting rates (on various surfaces, with temps around 33-34F when the changeover occurs), meaning significant melting will occur, especially where snowfall rates are light to moderate. This will be a nowcasting event for the most part.

One will need snowfall rates to exceed about 1/2" per hour to get decent accumulations going (and once a layer of snow is down it's at 32F, meaning the 32F falling snow will then have a much lower melting rate from the 33-34F air, i.e., maybe <1/8" per hour of melting). Also, with this storm, melting rates are greater for warmer paved surfaces, so this is likely to be a storm where snow primarily accumulates on grassy/colder surfaces with little on paved surfaces (unless there are surprisingly high rates in a few locations).

And predicting what locations will get snowfall rates high enough to get accumulating snow, especially on paved surfaces is very difficult, as areas of higher rates will be governed by mesoscale (on the order of tens of miles) processes for this storm, which are beyond the ability of our current models to discern well in advance. Anyway below are the latest maps from the NWS.




Ok kids, it's snowing! It's 32F with 1.25" of new snow on the ground on colder surfaces with a little slush in spots on paved surfaces, which is not surprising, so on the whole, this should generally be a nuisance snowfall, with regard to travel impacts. Judging by the radar, it turned to snow around 3 am along most of the 95 corridor, while I was sleeping and snowed at a decent clip until about 5:30 am, a little after I woke up.

Snowfall rate has lightened up a bit since then, but could still fill back in, although the 95 corridor does look to be on the NW side of the heavier bands. NWS forecast hasn't really changed much with 1-2" generally expected for most of the area. However, judging by the radar history, it looks like not much snow has fallen more than about 10-20 miles NW of the Route 1 from Philly to NYC. Could definitely see localized 3" amounts east of about a Hammonton to Hazlet line, where banding looks to be heaviest, although with temps slightly warmer there, wouldn't expect to see much on paved surfaces.