January 2022

[crossbowftw3]

1 minute ago, lee59 said:

If it becomes clear and the wind dies down, this could be the coldest night of the season in many suburbs.

From single digits and negatives to 30s and 40s within roughly 36 hours, pretty impressive swing overall 

[EasternLI]

Well if a very deep western trough shows up, there's going to be no shot at snow. So patterns are discussed. Rightfully so. None of those fine details would matter one bit. See December. Option B is zero discussion, which seems a bit odd on a discussion board. Or we can discuss shoes. 

[EastonSN+]

3 minutes ago, EasternLI said:

Well if a very deep western trough shows up, there's going to be no shot at snow. So patterns are discussed. Rightfully so. None of those fine details would matter one bit. See December. Option B is zero discussion, which seems a bit odd on a discussion board. Or we can discuss shoes. 

Agreed. Will be fun to see if it's a record trough again or something manageable. 

Personally I think we do fine in Feb. And great in March.

We shall see, part of the fun!

[eduggs]

31 minutes ago, bluewave said:

The long range pattern discussions have been doing very well this winter so far. Models were indicating a very warm and snowless December from as early as late November. This month we got a 6-10” snowstorm as soon as the Pacific flipped. While the 500 mb height anomalies for this last week were indicating cold, they never had the big classic snowstorm look for us. The PNA ridge was centered too far to the east indicating suppression potential for the ocean storm. The Monday cutter emerged due to the lack of blocking to hold the Canadian high in place over New England. 

That's all tainted with the benefit of hindsight. None of that was clear at the time. The fluke 0.4" liquid equivalent snowstorm occurring near the time the PNA was changing sign was a coincidence. The Pacific is still flipped right now - no snowstorm. And the recent anomaly maps have looked pretty classic for a big east coast snowstorm. 

[EasternLI]

2 minutes ago, EastonSN+ said:

Agreed. Will be fun to see if it's a record trough again or something manageable. 

Personally I think we do fine in Feb. And great in March.

We shall see, part of the fun!

I appreciate your thinking. My only real hope moving forward is that we do not see some late season SSW. Which would just mean an utterly lousy spring at that point. I'll pass on that. Otherwise, I'm not overly sure how things unfold exactly yet. It's a fascinating year, even though snow totals have been lousy so far. 

[bluewave]

1 minute ago, eduggs said:

That's all tainted with the benefit of hindsight. None of that was clear at the time. The fluke 0.4" liquid equivalent snowstorm occurring near the time the PNA was changing sign was a coincidence. The Pacific is still flipped right now - no snowstorm. And the recent anomaly maps have looked pretty classic for a big east coast snowstorm. 

Sure it was. But people that pointed it out in these threads were labeled as being anti snow or overly pessimistic. The PNA flip snowstorm potential was being discussed as far back as December. This matched past climo when long  -PNA or Western Trough intervals relaxed. As for this last week, that ocean storm was reliably modeled OTS. The trailing storm system to impact the area on Monday was too amped up with no blocking to hold the high pressure in place. So the OP runs did a great job indicating the cutter track. The GEFS low resolution showing a more easterly track were never designed to handle situations like this. So its always a matter of choosing the right forecast tool for the situation. 

[eduggs]

2 minutes ago, bluewave said:

Sure it was. But people that pointed it out in these threads were labeled as being anti snow or overly pessimistic. The PNA flip snowstorm potential was being discussed as far back as December. This matched past climo when long  -PNA or Western Trough intervals relaxed. As for this last week, that ocean storm was reliably modeled OTS. The trailing storm system to impact the area on Monday was too amped up with no blocking to hold the high pressure in place. So the OP runs did a great job indicating the cutter track. The GEFS low resolution showing a more easterly track were never designed to handle situations like this. So its always a matter of choosing the right forecast tool for the situation. 

I have no problem with using the models - both OP and ensembles - to forecast snowstorms in the extended medium range. I'm a vocal supporter of modeling and I believe guidance is clearly better than ever. My problem is using LR indices and anomaly charts to hunt for snowstorms. It's fine if you're an energy trader, but it works poorly for local weather forecasting.

[Allsnow]

The gfs now showing the potential snowstorm Friday night 

[Jt17]

Lol at gfs next weekend 

[Allsnow]

CCB Ownage for 95…

 

only 7 days to go 

[Jt17]

1 minute ago, Allsnow said:

CCB Ownage for 95…

 

only 7 days to go 

Looks like 20+ hours of snow 

[Allsnow]

Just now, Jt17 said:

Looks like 20+ hours of snow 

 

[Allsnow]

The next two weeks will determine if nyc finishes close to normal snowfall this winter IMO 

[donsutherland1]

Clouds will increase tomorrow. After a cold start, temperatures will rise through the 20s into the 30s.

A strong storm could bring snow changing to rain to much of the region late tomorrow night into Monday. A moderate to significant snowfall is likely across central and upstate New York into central and northern New England. Western and Upstate New York into Quebec could see a significant snowfall. Parts of those areas could pick up a foot or more of snow. Eastern New England and much of Long Island will likely experience mostly or all rain. High winds could produce coastal flooding especially during high tide on Monday morning.

Initial snowfall estimates:
Allentown: 1"-3"
Baltimore: 1"-3"
Bridgeport: 1" or less
New York City: 0.5" or less
Newark: 1" or less
Philadelphia: 1" or less
Poughkeepsie: 2"-4"
Washington, DC: 1"-3"

January commenced with an AO-/PNA- pattern. That typically favors somewhat cooler than normal readings in the East. For NYC, the January 1-10, 1991-2020 mean temperature for such cases was 33.5° (normal: 34.8°). The cold pattern developed during the opening week of the month. In New York City, the January 1-15 mean temperature was 32.9°. Based on the latest guidance, it appears that the colder pattern that is now in place could last until late in the month.

The PNA is positive and is likely to remain positive through at least January 24th. A positive PNA is associated with more frequent snowfalls in the Middle Atlantic region. However, big snowfalls typically occur when the AO is negative. Some of the guidance suggests that the AO could go negative around or just after January 18th for a time.

The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -1.1°C for the week centered around January 5. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -1.32°C and the ENSO Region 3.4 anomaly has averaged -1.05°C. La Niña conditions will likely persist through meteorological winter.

The SOI was -24.40 today.

The preliminary Arctic Oscillation (AO) was +1.087.

On January 13 the MJO was in Phase 8 at an amplitude of 1.698 (RMM). The January 12-adjusted amplitude was 2.069 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 90% probability that New York City will have a colder than normal January (1991-2020 normal). January will likely finish with a mean temperature near 31.1° (2.6° below normal).

 

[Rjay]

After a low of 9 I made it up to 17 today. 

[bluewave]

14 minutes ago, eduggs said:

I have no problem with using the models - both OP and ensembles - to forecast snowstorms in the extended medium range. I'm a vocal supporter of modeling and I believe guidance is clearly better than ever. My problem is using LR indices and anomaly charts to hunt for snowstorms. It's fine if you're an energy trader, but it works poorly for local weather forecasting.

While the long range 500 mb anomaly charts can identify patterns favorable for snow, it’s always better to wait until we get to within the 5 day window before getting overly invested in any individual snowfall opportunity. 

[EasternLI]

18z GFS is like a carbon copy setup of Monday for next weekend 

Like almost identical at H5 LOL

Trailing vort diving in at just the right time this run. If this ends up the same way.... 

 

 

[Rjay]

Just now, EasternLI said:

18z GFS is like a carbon copy setup of Monday for next weekend 

Like almost identical at H5 LOL

Trailing vort diving in at just the right time this run. If this ends up the same way.... 

 

 

I don't see a reason why it couldn't trend that way but we'll see.  

[binbisso]

moderate la nina  With above normal snowfall from DC through the Southeast, northern Gulf coast  Tennessee, Kentucky.  well below average snowfall for northern New England england  I guess Snowman 19 would have predicted that

[EasternLI]

3 minutes ago, Rjay said:

I don't see a reason why it couldn't trend that way but we'll see.  

Not a fan of how far west that ridge is on that run. Hopefully that adjusts some. Leaves too much room to amplify west of us. Or that trailing shortwave evaporates. 

[Rjay]

3 minutes ago, EasternLI said:

Not a fan of how far west that ridge is on that run. Hopefully that adjusts some. Leaves too much room to amplify west of us. Or that trailing shortwave evaporates. 

Yup.  No real block.  Ridge too far west.  We'll see.  

[HVSnowLover]

As many predicted GFS way west looks great verbatim but hope we don't get dejavu to this weekend.  

[HVSnowLover]

48 minutes ago, Allsnow said:

 

It honestly looks more long duration than tomorrows storm so if we get a hit out of this it could be a homerun but not getting my hopes up yet. 

[eduggs]

40 minutes ago, bluewave said:

While the long range 500 mb anomaly charts can identify patterns favorable for snow, it’s always better to wait until we get to within the 5 day window before getting overly invested in any individual snowfall opportunity. 

The LR anomaly charts identify fantasy patterns that might allow a potential threat to materialize. And sometimes those patterns turn out to have been fantasy (i.e,., model errors). Other times the potential threats do appear, but they affect Nashville or Cleveland. So the success ratio of snowstorm hunting is very very low. So I don't look out past day 10 at all because I think the guidance is almost as likely to give a head fake in the wrong direction as it is to correctly signal something favorable. The error bars associated with any metric out beyond day 10 are huge.

[EastonSN+]

I feel like we have to wait until the PNA starts to go negative to get our next big snow event. We do well when PNA starts to fall (pattern change storm).

[eduggs]

46 minutes ago, EasternLI said:

18z GFS is like a carbon copy setup of Monday for next weekend 

Like almost identical at H5 LOL

Trailing vort diving in at just the right time this run. If this ends up the same way.... 

 

 

It is eerily similar  Almost a perfect overlay if you match up the right time frames. In fact, at quick glance it almost looks like next weekend's storm would be more likely to cut. But most of the vorticity for next weekend is modeled upstream with PVA heading east or southeast. Today the vortmax has rounded the bend and PVA is moving northeastward. Such a subtle difference.

[MJO812]

It's funny how people are now worried about the next storm. Can we at least be happy the models are showing storm threats?

[EastonSN+]

I know I know Op. Run long range. Not saying this image will happen but just using for illustration purposes only!

This ends up sliding off the southeast coast BUT the PNA is starting to drop which should pump up SE ride and help get something like this to us.

[MJO812]

Hopefully the Volcano helped us and will turned the pattern cold until April.

[bluewave]

4 minutes ago, eduggs said:

The LR anomaly charts identify fantasy patterns that might allow a potential threat to materialize. And sometimes those patterns turn out to have been fantasy (i.e,., model errors). Other times the potential threats do appear, but they affect Nashville or Cleveland. So the success ratio of snowstorm hunting is very very low. So I don't look out past day 10 at all because I think the guidance is almost as likely to give a head fake in the wrong direction as it is to correctly signal something favorable. The error bars associated with any metric out beyond day 10 are huge.

Sometimes a 15 day ensemble teleconnection forecast will do better than an operational run for a snowstorm from 5 days. But you need to check which 500 mb parameters the ensemble is showing compared to past snowstorms. It’s easier to nail a KU event from weeks out when we get a verified SSW event in progress that results in strong blocking near Greenland. We got this last winter ahead of the SSW in January and also in February 2018 for the epic March. The historic January KU pattern in 2016 became more obvious when the KB block built back across the pole early in the month.