Jump to content
  • Member Statistics

    17,612
    Total Members
    7,904
    Most Online
    Vesuvius
    Newest Member
    Vesuvius
    Joined

December 2019


NYCweatherNOW
 Share

Recommended Posts

1 hour ago, David-LI said:

We do care about non snow events. The forum is pretty active in the summer.

 

For me I care about extreme weather events. In the summer I am discussing thunderstorms and tornadoes. In the winter I mainly hope for Blizzards. So maybe that's why folks right now are not too interested in non snow events since that's what we discuss most months. The next 2-3 months is our best chance for that epic Blizzard.

it's even more active when a historic heatwave is ongoing.  I almost get the same rush when it hits 100 degrees at the coast as I do when we have 20 inches of snow!

 

  • Like 1
Link to comment
Share on other sites

1 hour ago, bluewave said:

The December temperature departure may come down to what happens during the last week of the month. But you can see how the fast Pacific flow has kept much of the CONUS mild this month. A small pocket of cold has managed to hold on over the GL and NE. Next 10 days look like more of the same.

0642F006-B01B-4C2B-A335-27488DEF8082.thumb.png.05ccd473819e04f4a4f60c3e2c046412.png

B4F3067F-8E72-4804-B631-F37ADF5242CC.thumb.png.51ae88aa3e3e32fe46cdb0c79c725027.png

04C848E8-6B99-4672-B97E-BC2867311020.thumb.png.73a3117ad4ad43647307a79e7d569998.png

 

 

 

But Chris, does the departure even matter in this kind of a pattern?  We've seen plenty of so-called "cold" months that were predominantly rainy.

Link to comment
Share on other sites

1 hour ago, LibertyBell said:

we've let it go to waste many times before..... if we capitalized on every -NAO/-AO then NYC would average like 80 inches of snow a year lol.  An east-based -NAO and/or a bad PAC make snow much less likely.  I wish there were graphs that depicted exactly what type of neg NAO this would be.

 

It would be good to have the NYC annual snow fall totals for the 1600s and 1700s,  as that covers the 'Little Ice Age' interval. My guess is that snow totals were above the recent 50" averages, but surely there is some historical record somewhere.

 

  • Like 1
Link to comment
Share on other sites

1 hour ago, etudiant said:

It would be good to have the NYC annual snow fall totals for the 1600s and 1700s,  as that covers the 'Little Ice Age' interval. My guess is that snow totals were above the recent 50" averages, but surely there is some historical record somewhere.

 

That is an interesting question. While it was much colder back then, it was also drier than the modern era. There have been tree ring studies from NY that showed significant droughts during those years.Our precipitation has been increasing as the climate has warmed. So perhaps the last 25 years had more 50” seasons around NYC and Long Island than any peak 25 year LIA period. 

Link to comment
Share on other sites

A soaking rain is drenching the region. Some interior sections were experiencing some mixed precipitation this evening. By the time the storm departs, the northern Mid-Atlantic and southern New England regions will have picked up 1.00"-2.00" of precipitation. Locally higher amounts near or even in excess of 2.50" are possible.

As of 9 pm, New York City had received 0.37" rain. That brings the 2019 total to 49.39", which ranks 2019 as New York City's 37th wettest year on record just ahead of 2010 when 49.37" precipitation was recorded.

Over the next 1-2 weeks, variability will likely continue to define to weather. As a result, much of the region could see additional snowfall through December 26. Whether the major cities see a 6" or greater snowstorm could depend, in large part, on the state of the teleconnections at the time of any storminess.

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 -0.23°C and the ENSO Region 3.4 anomaly has averaged +0.67°C. These recent conditions are consistent with a weak El Niño. Nevertheless, a neutral ENSO remains the base case for Winter 2019-20 and the recent cooling in Region 3.4 suggests that the base case remains viable.

The SOI was -3.79 today.

Today, the preliminary Arctic Oscillation (AO) figure was +2.024. The AO has averaged +1.737 through the first 13 days of December.

Since 1950, 13 years saw the AO average +1.000 or above for the first 15 days of December, which is very likely this year. Only 3 (23%) wound up with a colder than normal December in New York City (which appears likely at present). The most recent such case was December 1988 when New York City had a mean December temperature of 35.9°.

No significant stratospheric warming event appears likely through December 22. However, a brief period of warming could commence late in the period at 2 mb and above. Wave 2 activity is forecast to remain relatively weak. Overall, the stratosphere is forecast to remain cold through the third week of December on the EPS.

On December 12, the MJO was in Phase 2 at an amplitude of 1.124 (RMM). The December 11-adjusted amplitude was 0.960.

Large differences between the EPS and GEFS persist beyond Day 10. The GEFS is notably colder than the EPS with much of North America covered by cold anomalies. To date, the colder idea has more often than not prevailed since late autumn.

When it comes to New York City's 4" or greater snowstorms during the second half of December, the AO is highly important. Since 1950, December 16-31 has seen 15 storms bring 4.0" or more snow to New York City. 73% occurred with an AO-. Further, 80% of the 6" or greater snowstorms during this timeframe occurred when the AO was negative. Even as the PNA and NAO had a lesser impact on the 4" or greater snowstorms, an NAO- was present in 70% of the 6" or greater snowstorms during that timeframe and a PNA+ was also present during 70% of the 6" or greater snowstorms.

Based on sensitivity analysis applied to the latest guidance, there is an implied 62% probability that December will wind up colder than normal in New York City.

 

 

  • Like 2
Link to comment
Share on other sites

Through 10 pm, New York City had picked up 0.49" rain. That brings year-to-date precipitation to 49.51". As a result, 2019 is the 37th wettest year on record.

With a 1.00"-2.00" storm total rainfall likely, with a possible figure as high as 2.50", New York City is now on the brink of reaching 50.00" precipitation for the second consecutive year. Since daily records were recorded starting in 1869, 33 prior years have seen 50.00" or more precipitation in New York City. 21/33 (64%) of those years occurred after 1970.

  • Like 3
Link to comment
Share on other sites

1 hour ago, David-LI said:

We are due for a big blizzard and I believe this is the winter it will happen

The metro has had several massive blizzards/storms in the last few years, 2015/2016/2018.  Granted I know not everyone cashed in on all three, but we've become so accustomed to big storms nowadays.  What we are really due for is a more front-loaded winter that has multiple smaller events and then by April we turn the switch to Spring and never look back.

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...