December Medium/ Long Range

[midatlanticweather]

Swing and a miss on 18z GFS 

 

[TSSN+]

Here comes gfs with another run sponsored by medical mushrooms.

[rjvanals]

18z GFS would be annoying 

[TSSN+]

1 minute ago, midatlanticweather said:

Swing and a miss on 18z GFS 

 

Not exactly. Just a odd solution but it has potential with that vort. Still snows in the area 

[ChillinIt]

NE MD Pummeled!!!! LOL

[midatlanticweather]

1 minute ago, TSSN+ said:

Not exactly. Just a odd solution but it has potential with that vort. Still snows in the area 

NE Maryland, pummeled! LOL!

This solution was nice. I would enjoy it. 

 

[Heisy]

Euro AI was more of a late blooming miller B. 18z gfs likely a step towards a more realistic solution like that. The 12z H5 run as absurd. 1/10000 type look. It’s a Miller b setup, we know how these go…


.

[TSSN+]

2 minutes ago, Heisy said:

Euro AI was more of a late blooming miller B. 18z gfs likely a step towards a more realistic solution like that. The 12z H5 run as absurd. 1/10000 type look. It’s a Miller b setup, we know how these go…


.

We don’t know how anything goes at 196hrs. For all we know storm could move 500 miles north or south in the next 1-2 days 

[CAPE]

Another wacky solution from the GFS at HH. Plenty of cold coming in from the NW with the amped western ridge and digging shortwave energy, but the Gulf is closed for business. Baroclinic boundary is pushed offshore where the low develops, and the moisture feed comes from the Atlantic- part of our region just gets in on it this run via an inverted trough(that always works lol). This sort of evolution would favor places further NE.

 

[stormy]

2 hours ago, winter_warlock said:

   Below  normal temps  in next 2 weeks

 

If this verifies, both the GEFS extended and Weeklies were incorrect 3 weeks ago.

[stormy]

7 minutes ago, CAPE said:

Another wacky solution from the GFS at HH. Plenty of cold coming in from the NW with the amped western ridge and digging shortwave energy, but the Gulf is closed for business. Baroclinic boundary is pushed offshore where the low develops, and the moisture feed comes from the Atlantic- part of our region just gets in on it this run via an inverted trough(that always works lol). This sort of evolution would favor places further NE.

 

When the "Gulf is closed for business" that is not good.

[Heisy]

We don’t know how anything goes at 196hrs. For all we know storm could move 500 miles north or south in the next 1-2 days 

Right, but as cape just alluded this overall setup favors NE. We’ll see how it goes, just making an observation


.

[poolz1]

The spacing looked better to me than 12z.  The dive out of Can was just a bit further east and did not dig as much.  Subtle variations to the ridge out west.  

[CAPE]

The advertised h5 pattern is amplified and progressive. We can get the southward dig with NS energy in this setup. With no help in the NA however (+NAO), the tendency will be for later/offshore development as cold comes southeastward with any significant shortwave energy. Probably need a little more luck than usual with wave timing.

[midatlanticweather]

Some snowflakes in the air and cold for Christmas are all good to me! If it can be more... cool! I will watch and hope, but I will not count on anything!  

 

[WxUSAF]

Happy hour is fun but that has “last 48 hour heartbreak” written  all over it. Would be nice if we could get a solution like the 12z euro from yesterday. Simple easy 3-6”. 
 

eta…gfs kinda leaves some energy along the front late Thursday and flips us to white rain. If that front wave can amp up more and also get more trailing energy, that could turn into something.

[clskinsfan]

18z RGEM with a pretty nice 2-4 thump out here on Sunday. I81 special. But we would take it. 

[WxUSAF]

26 minutes ago, clskinsfan said:

18z RGEM with a pretty nice 2-4 thump out here on Sunday. I81 special. But we would take it. 

If you or anyone else want a thread for this, I’d say go for it. Only 48 hours out.

[stormy]

The 18z GFS says the DROUGHT continues thru December 29 with no real relief in sight.

[CAPE]

1 hour ago, CAPE said:

The advertised h5 pattern is amplified and progressive. We can get the southward dig with NS energy in this setup. With no help in the NA however (+NAO), the tendency will be for later/offshore development as cold comes southeastward with any significant shortwave energy. Probably need a little more luck than usual with wave timing.

HH GEFS

[psuhoffman]

2 hours ago, rjvanals said:

18z GFS would be annoying 

Looks a lot like a typical cold enso HECS 

[Eskimo Joe]

2 hours ago, rjvanals said:

18z GFS would be annoying 

On brand for this area.

[psuhoffman]

1 hour ago, Eskimo Joe said:

On brand for this area.

Just so everyone knows I'm not just being a deb... there have been 35 NESIS events during a -ENSO including cold neutrals since 2000.  And full discloser I did include 2014 in this, even though you all know how much of an outlier I think that season was...if I excluded it these numbers would be a LOT worse!

Of the 35 NESIS events the average snowfall at BWI was 2.8"

71% were 3" or less

29% were 4"

17% were 6"

9% were 10"

The max was 15"

By far the highest probability of how an NESIS level storm will affect our area during a cold enso is with less than 4" of snow and that its VERY likely the heavy snow will miss us to the north or east.  That is just the probabilities based on the records.  

I am NOT saying it cannot snow or that we can't get a good snowstorm, just that the odds are against it and so I am not getting my hopes up by long range HECS type setups because history says those storms are very likely to miss us.  

Just for comparison there have been 25 NESIS events in warm enso years since 2000

The avg at BWI is 7.4"

only 40% were less than 4"

60% were 4" plus

44% were 6" plus

20% were 10" plus

The max was 29"

My advice is in a cold enso when we are tracking a major snowstorm at range...expect it to miss us to the north or east and to get a very minor event because that is what the probabilities say are by far the greatest odds...then be happy if it turns out to be the very rare fluke where we get a major event.  

Even in a warm enso our odds from range at a major threat being a BIG snow are below 50% but they are over double the chances in a cold enso.  

 

[mattie g]

Cool story, bro.

[T. August]

Informative post, psu. I do think you underestimate how many people just want to see accumulating snow at this point, HECS or not

[psuhoffman]

Lastly, 1 of the 4 storms that ended up a big cold enso snowstorm was maybe the biggest surprise snow ever but 3/4 were storms many on here identified as legit threats well in advance. One was that WAG I got right from 10 days out in 2011.  But what all 4 had in common was a trough diving well to our southwest with an amplified wave digging into the TN valley to our southwest. 3/4 also featured a rarity for a Nino which was a mature STJ moisture feed to our southwest.  
 

If we see those things it’s ok to think this could be one of the exceptions. And the day 8-9 thing is way too far out to put to bed yet, but runs that show some NS dominant event with a SW that barely digs to our latitude and has to stall and bomb to get us don’t excite me.  We all know how those actually play out. 

[psuhoffman]

5 minutes ago, T. August said:

Informative post, psu. I do think you underestimate how many people just want to see accumulating snow at this point, HECS or not

I predicted we will get snow this winter. Just not a lot and unlikely a big storm.  And I see posts that show us getting 1-3” saying “that would be frustrating” because it has northeast of us getting 20”.  That was what the impetus of my post was. For those that would be totally happy to get 1-2” of snow from a storm that crushes somewhere north or east of us with big snow they are being totally realistic and that’s healthy. Expecting is go get big snow then being upset when it hits the places climo favored in cold enso is not. That’s all. Everyone is different. 

[JenkinsJinkies]

48 minutes ago, psuhoffman said:

My advice is in a cold enso when we are tracking a major snowstorm at range...expect it to miss us to the north or east and to get a very minor event because that is what the probabilities say are by far the greatest odds...then be happy if it turns out to be the very rare fluke where we get a major event.  

Even in a warm enso our odds from range at a major threat being a BIG snow are below 50% but they are over double the chances in a cold enso.  

 

How would you feel if snow misses us to the south like in 2017-2018? The Capital Weather Gang even wrote an article back then that said something along the lines of "the number of southern cities that have more snow than DC this winter is embarassing".

[CAPE]

9 minutes ago, JenkinsJinkies said:

How would you feel if snow misses us to the south like in 2017-2018? The Capital Weather Gang even wrote an article back then that said something along the lines of "the number of southern cities that have more snow than DC this winter is embarassing".

It happens. Snow can fall to the south of us too. Always has. If that stops occurring, we are truly fucked.

[psuhoffman]

17 minutes ago, JenkinsJinkies said:

How would you feel if snow misses us to the south like in 2017-2018? The Capital Weather Gang even wrote an article back then that said something along the lines of "the number of southern cities that have more snow than DC this winter is embarassing".

There was a storm that winter with a distribution similar to Boxing Day. It didn’t miss south as much as east. There were some minor events that missed south. But that’s also Nina climo. The worst negative snow anomaly is right over the DC Balt area in cold enso. You’re more likely to get more snow wrt average in every direction.