December 2024

[SnoSki14]

4 hours ago, MJO812 said:

Bamwx snowfall outlook for January and February.

Lol sure Jan

[Stormlover74]

4 hours ago, MJO812 said:

Bamwx snowfall outlook for January and February.

Damn and I was going to head to San Francisco for snow

[donsutherland1]

New York City, Philadelphia, and Washington, DC have seen their coldest December 1-15 period since 2010. Boston has seen its coldest such period since 2013. Baltimore saw its coldest since 2017. Despite the cold, snowfall has been lacking. As a result, Boston has now gone 1,024 consecutive days without a 4" or greater daily snowfall (old record: 711 days). Richmond has gone 1,064 days without a 1" or above daily snowfall (old record: 725 days). Significant snowfall remains unlikely in this region for the foreseeable future.

Much milder air will return starting tomorrow. It will be unseasonably mild tomorrow and Tuesday. Additional rain is likely, as well. Following the rain, it will again turn somewhat colder before a much sharper shot of cold arrives for during or after the next weekend. The potential exists for the temperature to fall into the teens for the first time this season in New York City.

Beyond that, the pattern will likely remain changeable through much of the rest of the month on account of a fast jet stream.  The probability of a mild end to the month and mild start for the first few days of January has increased.

In recent days, an occasional run of the operational GFS showed a significant snowstorm from Washington, DC to New York City. However, the pattern makes such an event very unlikely for this region. Since 1950, there were 5 December snowstorms that brought 6" or more snow to all three of these cities. Four (80%) occurred with a PNA+/NAO- pattern. The NAO is forecast to be positive. In addition, three (60%) occurred when the MJO was in Phase 8, which is not likely over the next 10 days. Only the December 23-25, 1966 event produced 6" or more snow in all three cities with a positive NAO, but the AO was strongly negative (< -2.000), which is not likely during the next 10 days. In sum, the interior sections will be far more favored for an appreciable or perhaps greater snowfall than the Washington-Baltimore-Philadelphia-New York City area over the next 10 days. A smaller snowfall is plausible.

The NAO fell to a preliminary -2.751 on September 24th (all-time September record: -2.371, September 12, 1971). That was the 9th lowest value on record. La Niña winters following September cases where the NAO fell to -1.900 or below featured a predominantly positive NAO. The most recent such winters were 2016-2017 and 2022-2023. The mean temperatures for those winters in New York City were 39.3° and 41.0° respectively. The 1991-2020 normal value is 36.2°. A warmer to much warmer than normal outcome is favored by the November run of the ECMWF for Winter 2024-2025.

The ENSO Region 1+2 anomaly was +0.1°C and the Region 3.4 anomaly was -0.3°C for the week centered around December 4. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.12°C and the ENSO Region 3.4 anomaly has averaged -0.20°C. Neutral ENSO conditions may still evolve into a La Niña event during the winter. Uncertainty as to whether a La Niña will actually develop continues to increase. Currently, 47% of dynamical models and 22% of the statistical models forecast the development of a La Niña.

The SOI was +0.52 today.

The preliminary Arctic Oscillation (AO) was +1.573 today.

Based on sensitivity analysis applied to the latest guidance, there is an implied 83% probability that New York City will have a colder than normal December (1991-2020 normal). December will likely finish with a mean temperature near 36.9° (2.2° below normal).

 

[snowman19]

2 hours ago, Wxoutlooksblog said:

During 2010 we were saying the same thing two days before the storm. This is 7-8 days ahead. I also do not think the La Ninas or the overall weather regimes are comparable.

WX/PT

The fantasy on twitter is that Saturday is going to somehow miraculously, magically turn into some massive KU for the I-95 corridor and all the models are somehow missing it. This isn’t 2004, technology and the models are way advanced from the days when a massive snowstorm would just “pop up” out of nowhere 48 hours before an event. If this was actually going to be a big coastal snowstorm, one of the models would be showing that by now, which NONE of them are. And most importantly, the pattern in no way, shape or form supports such a scenario and no amount of wishcasting is going to change that

[bluewave]

Top 5 warmest last week of December possible for North America.

 

[vegan_edible]

3 minutes ago, snowman19 said:

The fantasy on twitter is that Saturday is going to somehow miraculously, magically turn into some massive KU for the I-95 corridor and all the models are somehow missing it. This isn’t 2004, technology and the models are way advanced from the days when a massive snowstorm would just “pop up” out of nowhere 48 hours before an event. If this was actually going to be a big coastal snowstorm, one of the models would be showing that by now, which NONE of them are. And most importantly, the pattern in no way, shape or form supports such a scenario and no amount of wishcasting is going to change that

3 years with no huge storms have some folks in a full-on delusional state 

[bluewave]

39 minutes ago, donsutherland1 said:

Based on sensitivity analysis applied to the latest guidance, there is an implied 83% probability that New York City will have a colder than normal December (1991-2020 normal). December will likely finish with a mean temperature near 36.9° (2.2° below normal).

That would be very close to average as recently as the 81-10 climate normals which was 37.5° in NYC.

https://www.ncei.noaa.gov/access/us-climate-normals/#dataset=normals-monthly&timeframe=81&location=NY&station=USW00094728

 

[donsutherland1]

6 minutes ago, bluewave said:

That would be very close to average as recently as the 81-10 climate normals which was 37.5° in NYC.

https://www.ncei.noaa.gov/access/us-climate-normals/#dataset=normals-monthly&timeframe=81&location=NY&station=USW00094728

 

Yes. The 1991-20 baseline is quite a bit warmer than the 1981-10 one.

[bluewave]

19 minutes ago, the_other_guy said:

stop being a raindrop on a barbecue dude. Seriously… I love your information…but lighten up with the doom and gloom a bit. Gonna be in the 40s.

We’ll have a shot at 50s to around 60 at some point during the last week of December. Many outside this forum don’t consider milder weather this time of year doom and gloom since it helps lower their winter heating bills. But it isn’t the greatest if you are running a ski resort during the holiday period.

[NEG NAO]

Even though its going to be above normal for a few days after the holidays IF todays model runs are accurate the cold will return right after the 1st of the new year and might stick around for a longer period of time as the MJO is progged to go into phase 8 too

[North and West]

Top 5 warmest last week of December possible for North America.


 

.

[qg_omega]

Only chance of snow this month is tonight, do we have an obs thread

[lee59]

4 minutes ago, North and West said:

.

Looks like all the cold air is in Greenland and stops pretty much at the border.

[qg_omega]

4 hours ago, sussexcountyobs said:

3,4,5 degrees above normal for the date, is not a massive torch.

Huh?  Looks record warmth, 15 to 20 above normal

[NEG NAO]

2 minutes ago, qg_omega said:

Huh?  Looks record warmth, 15 to 20 above normal

IMO its too far out to determine how much above normal........

[lee59]

3 minutes ago, qg_omega said:

Huh?  Looks record warmth, 15 to 20 above normal

I will take it more seriously a week from now.

[Wxoutlooksblog]

2 hours ago, snowman19 said:

The fantasy on twitter is that Saturday is going to somehow miraculously, magically turn into some massive KU for the I-95 corridor and all the models are somehow missing it. This isn’t 2004, technology and the models are way advanced from the days when a massive snowstorm would just “pop up” out of nowhere 48 hours before an event. If this was actually going to be a big coastal snowstorm, one of the models would be showing that by now, which NONE of them are. And most importantly, the pattern in no way, shape or form supports such a scenario and no amount of wishcasting is going to change that

I totally agree with what you say. While the above fantasy is possible and we cannot completely write off anything 6-7 days ahead, it is an extremely remote chance. 

WX/PT

[wdrag]

SB in Wantage NJ around 730P.. 30.0/23.

 

No obs thread from me since not a big deal for NYC but it will be slippery untreated pavements overnight not too far w-n of of NYC-frozen ground. 

[MJO812]

3 hours ago, SnoSki14 said:

Lol sure Jan

Another doom and gloom poster. You do know we get snow here right? It will eventually snow.

[sussexcountyobs]

Light snow falling . Whitening car and driveway. 31.9°

[Dark Star]

2 hours ago, snowman19 said:

The fantasy on twitter is that Saturday is going to somehow miraculously, magically turn into some massive KU for the I-95 corridor and all the models are somehow missing it. This isn’t 2004, technology and the models are way advanced from the days when a massive snowstorm would just “pop up” out of nowhere 48 hours before an event. If this was actually going to be a big coastal snowstorm, one of the models would be showing that by now, which NONE of them are. And most importantly, the pattern in no way, shape or form supports such a scenario and no amount of wishcasting is going to change that

Models are certainly improved since I was banging in 1981, but they have gotten dramatically better since 2004?  I've seen some > 5 day models actually get worse in the last few years...

[ForestHillWx]

Light snow in Chester; 3 stationary drones looking over the valley towards the Basking Ridge/Far Hills area. 

[ForestHillWx]

43 minutes ago, the_other_guy said:

I love how that moderator (who calls himself a professional :)) deleted my post but it lives on in your thread.

Hey Forky 

 

Back to weather, you and QQ skew too warm and run with any warm solution you see weeks out.

 

I have no doubt it will be a mild week. 

 

Too far out to declare it a Top 5 anything. 

 

Just like you didnt jump on a winter storm 10 days out

Bluewave/Forky are solid but I thought we leaned against taking 384 hour runs as gospel?

[eduggs]

17 minutes ago, Dark Star said:

Models are certainly improved since I was banging in 1981, but they have gotten dramatically better since 2004?  I've seen some > 5 day models actually get worse in the last few years...

Weather model improve every year. Verification is significantly improved since 2004. Regional synoptics are well resolved out to 5 days, whereas 20 years ago that was fantasyland territory. Surprise storms are a rarity these days.

Here are a couple of graphs of two verification parameters for the ECMWF. Other models may have improved more or less than these scored parameters indicate.

 

[Tatamy]

34 minutes ago, sussexcountyobs said:

Light snow falling . Whitening car and driveway. 31.9°

Have the same happening here.

[Stormlover74]

51 minutes ago, MJO812 said:

Another doom and gloom poster. You do know we get snow here right? It will eventually snow.

Why would Jan and Feb be above normal in snowfall? What is he basing that on?

[snywx]

29F w/ lgt snow falling

coating on all surfaces

[the_other_guy]

25 minutes ago, Stormlover74 said:

Why would Jan and Feb be above normal in snowfall? What is he basing that on?

I mean around here you get 1-10 inch storm in each and you are above normal right?

Not hard to bet the over if you want to make a headline. Especially if we keep getting these cold shots. Eventually something will click

[Stormlover74]

7 minutes ago, the_other_guy said:

I mean around here you get 1-10 inch storm in each and you are above normal right?

Not hard to bet the over if you want to make a headline. Especially if we keep getting these cold shots. Eventually something will click

True but out of our last 20 winter months only 4 have been above average. Dec 20, Feb 21, Jan 22 and Feb 24

[Tatamy]

46 minutes ago, snywx said:

29F w/ lgt snow falling

coating on all surfaces

Mix of Snow/sleet.  33F