November Medium/Long Range Discussion

[Solution Man]

48 minutes ago, bncho said:

that's a LOT better than i'd expect

Anybody wanna sign, I can work up a memo

[WxUSAF]

Those MJO analogs are variable based on ENSO and they’re not always high correlation. But if a wave moves into Phase 8 strongly in mid December, that should be supportive of cold and snow chances.

[frd]

1 hour ago, leo2000 said:

Yes, nothing awful about MJO phase 6 in December so of course phase 7 would be even better. 

 

 

Phase 6, La Nina DEC

 

Thats does not seem to match what I am looking at. There are many MJO models and many possible outcomes. As @psuhoffman mentioned a couple days ago, having a great Pac in December, versus a - NAO is a more realistic path to cold and snow in our area, and I totally agree.

The Pac has screwed us several times in recent years and the - NAO is hard to predict. Its occurrence ( -NAO )  does not in any way guarantee snow. The block one year dived far to the SW that we warmed up and Texas had a blizzard. Another year it linked with the SER, and yet another year Canada was so warm the -NAO was useless. 

I would say a lot in December depends on the Pac. If things fall apart there then the hopes of a wintry December will not happen. 

   

[leo2000]

1 hour ago, frd said:

 

Thats does not seem to match what I am looking at. There are many MJO models and many possible outcomes. As @psuhoffman mentioned a couple days ago, having a great Pac in December, versus a - NAO is a more realistic path to cold and snow in our area, and I totally agree.

The Pac has screwed us several times in recent years and the - NAO is hard to predict. Its occurrence ( -NAO )  does not in any way guarantee snow. The block one year dived far to the SW that we warmed up and Texas had a blizzard. Another year it linked with the SER, and yet another year Canada was so warm the -NAO was useless. 

I would say a lot in December depends on the Pac. If things fall apart there then the hopes of a wintry December will not happen. 

   

I got this from Grace over in wx sphere she seems pretty knowledgeable about the weather. Of course the Pacific is the driver it can make make or break Winter. I would not worry though we are going to have a strong negative EPO and a positive Pna or negative Pna. 

[Eskimo Joe]

Some of the short term guidance is trying to hint at a sneaky cold Monday morning for the NW suburbs...perhaps even down to the upper 20s.

[Eskimo Joe]

 

[Jebman]

Sorry guys. Off topic. I deleted it. I am VERY sorry.

[WxUSAF]

Obviously all the details TBD, but it seems like every operational run the last couple days has some big Arctic outbreak happening or on the way Thanksgiving weekend. Out west and Plains favored, but plausible some cold gets to us behind a rainy cutter.

[leo2000]

1 hour ago, WxUSAF said:

Obviously all the details TBD, but it seems like every operational run the last couple days has some big Arctic outbreak happening or on the way Thanksgiving weekend. Out west and Plains favored, but plausible some cold gets to us behind a rainy cutter.

Some of the operational runs bring it more out east. We will have to see. 

[Eskimo Joe]

**inhales deeply**

 

 

[Weather Will]

Latest WB EPS weeklies 30 day period ending Dec. 31.

[bncho]

17 minutes ago, Weather Will said:

Latest WB EPS weeklies 30 day period ending Dec. 31.

5 inches of snow in DC, about 2.5x of climo. that's great! but like @WxUSAF implies sometimes, i'd rather get that 2.5x climo in january or february (which is 12.5" instead of 5")

[CAPE]

3 minutes ago, bncho said:

5 inches of snow in DC, about 2.5x of climo. that's great! but like @WxUSAF implies sometimes, i'd rather get that 2.5x climo in january or february (which is 12.5" instead of 5")

A 7 day snow map is barely worth a piss lol. These maps are nothing more than a wild ass guess. Posting them is silly, but I guess it's fun?

[NorthArlington101]

3 minutes ago, CAPE said:

A 7 day snow map is barely worth a piss lol. These maps are nothing more than a wild ass guess. Posting them is silly, but I guess it's fun?

I feel like some years the weeklies show jack squat in December. My only takeaway is that we’ll probably have an opportunity or two  

[CAPE]

6 minutes ago, NorthArlington101 said:

I feel like some years the weeklies show jack squat in December. My only takeaway is that we’ll probably have an opportunity or two  

Well yeah, in general the extended products suggest we may have a shot at seeing actual flakes in Dec. A rarity lately. Hopefully it will at least be on the cold side.

[Ji]

A 7 day snow map is barely worth a piss lol. These maps are nothing more than a wild ass guess. Posting them is silly, but I guess it's fun?

lol. You are in. Midseason form. Relax. When do weeklies ever show this on Nov 17

[CAPE]

5 minutes ago, Ji said:

lol. You are in. Midseason form. Relax. When do weeklies ever show this on Nov 17

No idea. I never look at 45 day snow maps lol.

[psuhoffman]

On 11/15/2025 at 11:21 AM, frd said:

 

Thats does not seem to match what I am looking at. There are many MJO models and many possible outcomes. As @psuhoffman mentioned a couple days ago, having a great Pac in December, versus a - NAO is a more realistic path to cold and snow in our area, and I totally agree.

The Pac has screwed us several times in recent years and the - NAO is hard to predict. Its occurrence ( -NAO )  does not in any way guarantee snow. The block one year dived far to the SW that we warmed up and Texas had a blizzard. Another year it linked with the SER, and yet another year Canada was so warm the -NAO was useless. 

I would say a lot in December depends on the Pac. If things fall apart there then the hopes of a wintry December will not happen. 

   

When I isolated all our December snowfalls and looked at what factors seemed to be most common by far the PNA and EPO had to be favorable.  With the caveat that the AO is still the most common indicator.  But that is universal across every possible pattern and time of year.  If the AO is positive it's just hard for the jet stream to be suppressed enough to get a system to stay under us.  But in terms of the pacific (EPO/PNA) v atlantic (NAO) the pacific was definitely more important.  Not necessarily both but it was almost unheard of to get a snowfall early in the season if both the EPO and PNA were unfavorable.  Having the NAO also certainly helps...but the NAO alone without any help from the PNA/EPO doesn't do us much good in December.