December 2025 OBS and Discussion

[NEG NAO]

6 minutes ago, MJO812 said:

So you are believing the guidance as it is on right now ? We are in phase 8. Some of you are gloom and doom all the time. 

How many times have the models showed nothing until it got closer ? Phase 8 promotes storming.

Our time is coming 

first of all you know for a fact I am not gloom and doom all the time as we have agreed many times on here. Secondly the only guidance I can believe right now is what is being produced as of today - of course with borderline temps shown today can trend colder in coming days. And of course our time is probably coming as seasonal trends begin to favor more frozen solutions as we get deeper into the winter season.

[NEG NAO]

4 minutes ago, anthonymm said:

Cold dry warm wet. If we don't have HP the north then Dec 12 will be rain for the city. If we do it'll suppress south to Virginia. NYC metro is a really unlucky spot now for snow. Too south for the marginal/interior tracks, too north for the supressively cold tracks. Only way to get snow now is with benchmark tracks, which not even the fantasy GFS is showing. Likely <3" December---> low snow winter #4 of the 2020s.

How you can predict total monthly snowfall on December 6th is beyond me............

[Roger Smith]

1 hour ago, Dark Star said:

I never did learn how to read these things...

Presumably the tracked component began on Oct 27 and its motion is prograde at low latitudes so the closer it gets to the center of the circle, the closer to the equator it has tracked. The current location is where the red portion of the track begins (on Dec 5 as posted). The labels around the outside of the graph show that the frame of reference is as follows ... left is around 60 deg W longitude (tropical N Atlantic near Trinidad), bottom is around 30 deg east (east Africa), right is 120 deg E (w Indonesia) and the top of the square is 150 W (south of Hawaii). 

The component being tracked (almost always a generally prograde motion from west to east, you can see one brief retrograde period labelled early Nov) is anomalous tropical convection. The MJO assumption is that this will anchor the dynamics of the higher latitude ridge-trough pattern that drives the jet stream in the mid-latitudes. 

So to sum up, the diagram tracks the motion of this forcing over about two months with 45 past days and 15 future days projected. In this case the feature has crossed the equatorial Pacific and moved across at least part of central America where it has begun to drift closer to the equator. It is progged to continue that motion for 2-3 days and then slowly reverse back towards the subtropics. There is no longer-range projection shown but one could assume the later December into January track would take it across Africa into the Indian Ocean. But I don't follow it myself, just aware of what others think it may mean to long-range prospects. 

Because it's not my main focus I may have some of these details wrong, so perhaps somebody more familiar with the diagram can set us straight. I think the phrase Maritime Continent is a reference to the many islands of Indonesia and the Philippines as well as Australia and New Zealand in general terms. What I would not swear to is that the diagram is meant to convey equal differentials of longitude, it may be somewhat schematic on that, and the scale of the latitude range is not really clear but I assume the circle is the tropic of Cancer and the center of the diagram is the equator. It would probably be rare for the tracked component to get to any latitude much greater than 25 N. 

[jm1220]

11 minutes ago, NEG NAO said:

first of all you know for a fact I am not gloom and doom all the time as we have agreed many times on here. Secondly the only guidance I can believe right now is what is being produced as of today - of course with borderline temps shown today can trend colder in coming days. And of course our time is probably coming as seasonal trends begin to favor more frozen solutions as we get deeper into the winter season.

Doesn’t matter what any of us think-it’s what the pattern supports and how any storm evolves. Hopefully we can get an outcome where the S/W can dig and amplify close SE of us and there’s some blocking, so any high pressure isn’t booted east, and the storm will develop offshore and keep winds out of the north. We’ve seen that fast zonal flow either brings what we saw yesterday with suppression, or inland tracks/unfavorable lead up to the storm like early in the week. Could we see a good outcome on 12/13 or later in the month? Definitely and I hope so, but we need pretty significant mid latitude pattern changes to what we have now. Those are just facts and it doesn’t matter much whether the MJO is officially Phase 8 or whatever when other factors override it. 

[EastonSN+]

Plenty of extinct clippers on the guidance. If one digs enough we can get a light event.

[brooklynwx99]

12-13th might be an actual window to watch. nice to see the ridge out west trend taller, which helps shift the trough west as well

[NorthShoreWx]

Driving home around 9PM last night on the LIE in eastern Nassau County we encountered a blizzard of salt.  It continued until we passed the spreader which was salting the highway for some unknown reason.  This was traditional rock salt, not brine.

[bluewave]

10 minutes ago, NorthShoreWx said:

Driving home around 9PM last night on the LIE in eastern Nassau County we encountered a blizzard of salt.  It continued until we passed the spreader which was salting the highway for some unknown reason.  This was traditional rock salt, not brine.

Has been a common theme in recent years with the heavy road salting especially behind the 18-wheelers.