January 2019 General Discussion & Observations

[weathermedic]

I know what they are banking on but lots of dry air to overcome with very light precip rates (if any) from staying virga. 

[Brasiluvsnow]

1 minute ago, Snow88 said:

They are banking on some overrunning precip with the very cold temps for ratios.

Quite possible

Its a pretty sorry state of affairs when we are hoping / begging for an inch or possibly 2 but thats where we are at thus far this season.

[NJwx85]

We could see a brief burst of snow very late Saturday night while the surface low is developing off OBX.

[SnoSki14]

I do not see cold & dry at all. Pattern looks very active, we may see several gradient type events. 

Very cold air nearby. I think a heavy snowfall event or two is highly likely before the month ends. It'll get even better in Feb. 

[LongBeachSurfFreak]

27 minutes ago, SnoSki14 said:

I do not see cold & dry at all. Pattern looks very active, we may see several gradient type events. 

Very cold air nearby. I think a heavy snowfall event or two is highly likely before the month ends. It'll get even better in Feb. 

I agree plenty of cold air and there will be moisture. The question at this range is where does the gradient set up. If we can move what Maine has been seeing down to our latitude we are in the goods. Obviously in a gradient pattern you want to be on the edge. Too far north and it’s fridged and sunny, south and it’s rain and mild. 

[RU848789]

Keep in mind that those NWS graphics were only through 7 am on Sunday.  New OKX map shows through 1 pm and haven't seen a new PHI map.  Not that it made much difference, since <1" is still the general forecast for all of the NYC region; for the Philly region we should still expect a few inches south of about Wilmington to AC...

[NycStormChaser]

6 minutes ago, RU848789 said:

Keep in mind that those NWS graphics were only through 7 am on Sunday.  New OKX map shows through 1 pm and haven't seen a new PHI map.  Not that it made much difference, since <1" is still the general forecast for all of the NYC region; for the Philly region we should still expect a few inches south of about Wilmington to AC...

FYI this still says through 7am but agreed about the new one being the same. 

[RU848789]

14 minutes ago, NycStormChaser said:

FYI this still says through 7am but agreed about the new one being the same. 

Fixed it - no idea why it didn't paste correctly before (cache issue maybe - had to paste to FB, then paste here to get the right graphic here)...

[weatherpruf]

3 hours ago, RU848789 said:

We don't need a met for this discussion - this is purely a stats discussion and there aren't enough data points to be making conclusions or even correlations between many of the things being posited around here, like a big storm in Nov and snowfall outcome after that - typically one needs a few dozen data points.  The stats rule of thumb has always been that one needs 30 data points to ensure statistical significance - that truly depends on the system and the data, but it's still a decent rule of thumb, and there's no question that <10 and especially <5 data points is not statistically significant for establishing correlations.  

https://statswithcats.wordpress.com/2010/07/11/30-samples-standard-suggestion-or-superstition/

There is too small a sample for Nov, but I'm not so sure about December; while I am not a scientist, I will never make things up out of whole cloth ( former journalist, from an era when that meant you didn't present both sides of an issue if one of the sides was malarkey, think climate change "debate" ) I first learned of the association between low snow Decembers and low snow winters from a Rutgers meteorologist. Specifically, he cited New Brunswick patterns. He was quoted in the Star Ledger IIRC; this was a long time ago, but has generally been true as long as I've lived in the area, with a few exceptions, like 2015, and 2016 ( though we got most if not all of the seasonal average in one big storm ). But even then I wonder how robust that is; sounds more like a rule of thumb than a hard and fast rule. Most weather pros will tell you one can never rule out a big snow in any winter, even a mild one. 

[RU848789]

9 minutes ago, weatherpruf said:

There is too small a sample for Nov, but I'm not so sure about December; while I am not a scientist, I will never make things up out of whole cloth ( former journalist, from an era when that meant you didn't present both sides of an issue if one of the sides was malarkey, think climate change "debate" ) I first learned of the association between low snow Decembers and low snow winters from a Rutgers meteorologist. Specifically, he cited New Brunswick patterns. He was quoted in the Star Ledger IIRC; this was a long time ago, but has generally been true as long as I've lived in the area, with a few exceptions, like 2015, and 2016 ( though we got most if not all of the seasonal average in one big storm ). But even then I wonder how robust that is; sounds more like a rule of thumb than a hard and fast rule. Most weather pros will tell you one can never rule out a big snow in any winter, even a mild one. 

I've been doing chemical eng'g science, including tons of statistical analyses for 35+ years.  I can assure you that the biggest reason low snow Decembers lead to low snow winters is because of low snow Decembers.  I'm being a little tongue in cheek here.  The point is, if you start off 4-5" behind where climo (4.8" normally in Dec, which is almost 20% of the 25" seasonal avg) would normally put you at the end of Dec and you assume that, on average the rest of winter is average, then all of those winters would be 4-5" behind climo for the whole winter.  People try way too hard to find correlations and causations that aren't there or that are far more complex than needed.  Occam's Razor usually applies.  

[Gravity Wave]

18z GFS is back to the big bomb for the 20th.

 

E: And it follows it up with a redeveloping clipper on the 22nd and another big coastal for the 26th. Active, to say the least.

[MJO812]

Weeklies are great moving forward

Gefs looks great for the 20th

Winter is coming

[sussexcountyobs]

Ahhh yes. The elusive hr 240 big snowstorm.....

[NycStormChaser]

3 minutes ago, sussexcountyobs said:

Ahhh yes. The elusive hr 240 big snowstorm.....

Where have I heard that before 

[MJO812]

3 minutes ago, sussexcountyobs said:

Ahhh yes. The elusive hr 240 big snowstorm.....

Every op and ensemble have it.

[Ericjcrash]

Starting to tick NW on guidance, to bad its ticking back from Bermuda.

[MJO812]

1 minute ago, NycStormChaser said:

Where have I heard that before 

There is a difference between a pattern that supports a storm and a pattern that doesn't.

Remember , we had a lag with the ssw and the time is coming up shortly.

Buckle up

[sussexcountyobs]

6 minutes ago, Snow88 said:

Every op and ensemble have it.

Believe me, I hope your right Ant, but how many times over the years have we been let down on these 10 day out model runs.

[donsutherland1]

The current cold shot will see temperatures fall to perhaps their coldest levels since November 23 tonight. Readings outside New York City will likely bottom out in the teens. The low temperature Saturday morning could even fall below 20° in New York City.

The SOI was -7.30 today. It has now been negative for 10 out of the last 11 days.

The AO was -1.914. That is the lowest figure so far during the current meteorological winter and the 5th consecutive day the AO has been negative. The preliminary average for meteorological winter has now fallen to +0.035.

On January 9, the MJO was in Phase 8 with an amplitude of 2.056 (RMM). That amplitude was somewhat lower than the January 8-adjusted figure of 2.333.

Considerable uncertainty exists for the MJO's medium-term forecast. Both the GEFS and EPS forecast the MJO to move to low amplitude values through Phase 8. The Canadian ensembles bring it to Phase 5 with an amplitude of 1.000 or above. For now, with the MJO only slowly losing amplitude and the greater consistency of the statistical guidance, the baseline scenario remains the MJO's gradually moving through Phase 8 at a high but lowering amplitude. It would then move into Phase 1 and probably into a low amplitude shortly afterward. As that happens, the AO could have some positive fluctuations before it returns to mainly negative values.

Baltimore and Washington, DC could have their biggest snowfall so far this season. To date, the biggest snowfall at both locations occurred during the November 15-16, 2018 snowstorm. That storm's accumulations were:

Baltimore: 1.7"
Washington, DC: 1.4"

The potential exists for 3"-6" in Washington, DC and possibly Baltimore. 2"-4" with locally higher amounts appears likely across southeastern Pennsylvania and southern New Jersey. Lesser amounts appear likely north of there, especially from central New Jersey northward across New York City and Long Island. Central Park could pick up a small accumulation of snow.

Since 1950, 32% of January storms that brought 3"-6" snow to Washington, DC saw less than 2" fall in New York City. 86% of those storms occurred when the ENSO Region 3.4 anomaly was > 0°C. In contrast, 43% of the storms that saw 3"-6" snow in Washington, DC and 2" or more in New York City occurred with a positive ENSO Region 3.4 anomaly. In short, the kind of storm that appears likely given the guidance has been more common with positive ENSO Region 3.4 anomalies as is currently the case.

Nevertheless, the prospects for snowfall in and around the New York City area will likely remain above climatology for at least the next two weeks, if not longer given the expected evolution of the teleconnections.

A predominant AO-/PNA+ combination is likely after mid-month. Some of the guidance has hinted at the development of strong to perhaps severe blocking. An AO-/PNA+ combination has been present for most of the region's big January snowstorms. Since 1950, 68% of New York City's and 69% of Philadelphia's 6" or greater January snowfalls occurred with a AO-/PNA+ combination.

All said, the potential for above normal monthly snowfall remains on the table for such cities as Washington, Baltimore, Harrisburg, Philadelphia, Allentown, New York, Islip, and possibly Providence and Boston (where 0.2" snow has fallen to date, 2nd lowest such figure since winter 1999-00 when no measurable snow had fallen through January 10).

[MJO812]

10 minutes ago, sussexcountyobs said:

Believe me, I hope your right Ant, but how many times over the years have we been let down on these 10 day out model runs.

I'm not predicting anything but giving up on winter this early is foolish.

4 minutes ago, donsutherland1 said:

The current cold shot will see temperatures fall to perhaps their coldest levels since November 23 tonight. Readings outside New York City will likely bottom out in the teens. The low temperature Saturday morning could even fall below 20° in New York City.

The SOI was -7.30 today. It has now been negative for 10 out of the last 11 days.

The AO was -1.914. That is the lowest figure so far during the current meteorological winter and the 5th consecutive day the AO has been negative. The preliminary average for meteorological winter has now fallen to +0.035.

On January 9, the MJO was in Phase 8 with an amplitude of 2.056 (RMM). That amplitude was somewhat lower than the January 8-adjusted figure of 2.333.

Considerable uncertainty exists for the MJO's medium-term forecast. Both the GEFS and EPS forecast the MJO to move to low amplitude values through Phase 8. The Canadian ensembles bring it to Phase 5 with an amplitude of 1.000 or above. For now, with the MJO only slowly losing amplitude and the greater consistency of the statistical guidance, the baseline scenario remains the MJO's gradually moving through Phase 8 at a high but lowering amplitude. It would then move into Phase 1 and probably into a low amplitude shortly afterward. As that happens, the AO could have some positive fluctuations before it returns to mainly negative values.

Baltimore and Washington, DC could have their biggest snowfall so far this season. To date, the biggest snowfall at both locations occurred during the November 15-16, 2018 snowstorm. That storm's accumulations were:

Baltimore: 1.7"
Washington, DC: 1.4"

The potential exists for 3"-6" in Washington, DC and possibly Baltimore. 2"-4" with locally higher amounts appears likely across southeastern Pennsylvania and southern New Jersey. Lesser amounts appear likely north of there, especially from central New Jersey northward across New York City and Long Island. Central Park could pick up a small accumulation of snow.

Since 1950, 32% of January storms that brought 3"-6" snow to Washington, DC saw less than 2" fall in New York City. 86% of those storms occurred when the ENSO Region 3.4 anomaly was > 0°C. In contrast, 43% of the storms that saw 3"-6" snow in Washington, DC and 2" or more in New York City occurred with a positive ENSO Region 3.4 anomaly. In short, the kind of storm that appears likely given the guidance has been more common with positive ENSO Region 3.4 anomalies as is currently the case.

Nevertheless, the prospects for snowfall in and around the New York City area will likely remain above climatology for at least the next two weeks, if not longer given the expected evolution of the teleconnections.

A predominant AO-/PNA+ combination is likely after mid-month. Some of the guidance has hinted at the development of strong to perhaps severe blocking. An AO-/PNA+ combination has been present for most of the region's big January snowstorms. Since 1950, 68% of New York City's and 69% of Philadelphia's 6" or greater January snowfalls occurred with a AO-/PNA+ combination.

All said, the potential for above normal monthly snowfall remains on the table for such cities as Washington, Baltimore, Harrisburg, Philadelphia, Allentown, New York, Islip, and possibly Providence and Boston (where 0.2" snow has fallen to date, 2nd lowest such figure since winter 1999-00 when no measurable snow had fallen through January 10).

Did you see the weeklies and gefs? 

Non stop cold and snow

[donsutherland1]

Just now, Snow88 said:

 

Did you see the weeklies and gefs? 

Non stop cold and snow

Not yet. That's encouraging to hear.

[snowheavyattimes]

11 minutes ago, sussexcountyobs said:

Believe me, I hope your right Ant, but how many times over the years have we been let down on these 10 day out model runs.

I’m not buying until we’re within 72 hours, maybe even 48.

[MJO812]

Just now, snowheavyattimes said:

I’m not buying until we’re within 72 hours, maybe even 48.

Models shouldn't even go out past 120 hours

[NEG NAO]

1 minute ago, snowheavyattimes said:

I’m not buying until we’re within 72 hours, maybe even 48.

I agree - we have been sent so many false signals the last month - everthing10days away - its time to curb the enthusiasm - what happens if the MJO goes into the warm phase 5 as advertised by the Canadian ? Could be a relatively short cold spell ………..

[JustinRP37]

8 minutes ago, NEG NAO said:

I agree - we have been sent so many false signals the last month - everthing10days away - its time to curb the enthusiasm - what happens if the MJO goes into the warm phase 5 as advertised by the Canadian ? Could be a relatively short cold spell ………..

Unfortunately if there was one giant 36 incher and then back to the upper 40s and 50s, many would say wow look I predicted a ton of snow and we got it! I know I have said it many times, but snowfall is just one part of a 'good' winter. The other is days with snow cover and finally number of nights that snow can be made at the local ski areas. I am hopeful based on current guidance that we are through the roughest part. Many local ski areas should be at or near 100% open by this weekend (late, but thankfully we had that November cold snap). 

[sussexcountyobs]

19 minutes ago, Snow88 said:

I'm not predicting anything but giving up on winter this early is foolish.

Did you see the weeklies and gefs? 

Non stop cold and snow

I never give up.

[MJO812]

Just now, sussexcountyobs said:

I never give up.

That's the spirit =)

[sussexcountyobs]

That's how I roll. Don't know where to get weeklies and models and all that crap. I just go by my experience here in Sussex county.  We usually always do good.  And I'm confident we'll get close to our average snowfall. Around 55"

[weatherpruf]

1 hour ago, RU848789 said:

I've been doing chemical eng'g science, including tons of statistical analyses for 35+ years.  I can assure you that the biggest reason low snow Decembers lead to low snow winters is because of low snow Decembers.  I'm being a little tongue in cheek here.  The point is, if you start off 4-5" behind where climo (4.8" normally in Dec, which is almost 20% of the 25" seasonal avg) would normally put you at the end of Dec and you assume that, on average the rest of winter is average, then all of those winters would be 4-5" behind climo for the whole winter.  People try way too hard to find correlations and causations that aren't there or that are far more complex than needed.  Occam's Razor usually applies.  

Interesting. A short piece in a newspaper wouldn't go into that kind of explanation, but it makes perfect sense. But it is human nature to try to find a reason for things, even when our ability to draw conclusions is limited. The article IIRC was also during a period of time that wasn't particularly snowy, possibly early 90's. My wife is in the sciences and my son is studying ecology at Rutgers, so they have a better grip on stats than I do, although we use them extensively in the social sciences to measure program effectiveness. But it ain't quite the same. Really appreciate your input over the years here. I pretty much rely on your reports to figure how much snow is out there, although on a few occasions there's some differences. Cheers.

[wdrag]

Posting results of long term guidance in the Dec 26-31 range: In a nutshell, the low pressure winter event of Jan 8 was not as anticipated via modeling in late December. The low was split into two events in 24 hours-further north and therefore warmer. The attendant snows and wake CAA lake effect beneath the deep trough aloft resulted in decent snows.  I even heard of plowing/salting w school delays in Pike County ne PA this Thursday morning (higher terrain of Dingmans and Milford PA), which is adjacent Sussex County NJ.  So it wasn't as much as anticipated but without decent extended modeling (1960's-1980s versions), we wouldn't have had much of an idea, including specific dates for cold outbreak, and specific dates of the events as poor mans ensembled in the Dec 26-31 notes.  I'll add this image below to that verification on p2, by Jan 12.   Posted 736P 1/10/19