December 2024

[MJO812]

6 minutes ago, David-LI said:

That's a short range model. At hour 69 it's not too accurate. 

Next run it will have nothing 

[the_other_guy]

4 hours ago, Allsnow said:

Congrats @MJO812

Don’t be a dick guys! he saw it and you guys kept saying nothing was happening

 

If we get a flake of snow, he was more accurate than most of you on here… a week out

[MJO812]

3 minutes ago, the_other_guy said:

Don’t be a dick guys! he saw it and you guys kept saying nothing was happening

 

If we get a flake of snow, he was more accurate than most of you on here… a week out

Let them troll me. It's all good.

[donsutherland1]

A cooling trend is getting underway. That trend will culminate with a sharp shot of cold will during the weekend. The temperature will likely fall into the teens for the first time this season in New York City and Philadelphia. Many areas outside those cities will likely experience single-digit lows.

Before that, a system will bring some periods of rain tonight into tomorrow. Afterward, another system will likely bring some periods of light snow to the region late Friday into early Saturday morning. A minor accumulation is possible in the Philadelphia to New York City region. Boston will likely pick up 1"-3" of snow.

Beyond that, the cold will recede beginning around the middle of next week.  December will likely close with above normal temperatures. The opening days of January will likely also begin with above normal temperatures. Snowfall prospects will remain limited.

On account of a lack of snowfall, 2023-2024 will likely set a new records for the lowest snowfall over a two-year period for Boston and New York City.

Boston: 2023-2024 Total to Date: 21.5"; Record: 38.2", 1979-1980
New York City: 2023-2024 Total to Date: 9.8"; Record: 17.4:, 1997-1998

In past 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 remains plausible. One example will be the upcoming Friday-Saturday snowfall in parts of the region.

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 -0.2°C and the Region 3.4 anomaly was -0.6°C for the week centered around December 11. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.17°C and the ENSO Region 3.4 anomaly has averaged -0.27°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 +17.33 today.

The preliminary Arctic Oscillation (AO) was -0.109 today.

Based on sensitivity analysis applied to the latest guidance, there is an implied 79% probability that New York City will have a colder than normal December (1991-2020 normal). December will likely finish with a mean temperature near 37.3° (1.8° below normal).

 

[bluewave]

12 minutes ago, the_other_guy said:

Don’t be a dick guys! he saw it and you guys kept saying nothing was happening

 

If we get a flake of snow, he was more accurate than most of you on here… a week out

Getting 3” or more is all that most of us care about in NYC. So far that doesn’t look like it’s in the cards. But a light accumulation or no accumulation seems to be what’s on the menu now. 

[MJO812]

Gfs is alot flatter and colder with the Christmas wave.

[psv88]

55 today. Beautiful 

[Brian5671]

1 minute ago, psv88 said:

55 today. Beautiful 

warmer and sunnier than expected

[the_other_guy]

Belleayre today. snow after 3pm

[SnoSki14]

1 hour ago, Brian5671 said:

warmer and sunnier than expected

If it's not gonna snow then I'll take that everyday this winter

[North and West]

That's a short range model. At hour 69 it's not too accurate. 

.