Wes' latest CWG post about Dec snow: calls forecast pattern "snow lover's nightmare"

[usedtobe]

A good news bad news type post. As YorkPA pointed out the 06Z GFS does show a really marginal set up for snow in the dc area/ The soundings are isothermal (temps don't vary much with height) and right along the zero C line at 96 to 108 hrs (I don't remember the exact timing). The UKmet like a low with a slightly more northerly track (rain) while the crummy version of the euro makes it look like the system might be sheared enuf to miss us. So snow lovers, there is something to watch though I'm still not that excited about it. That's the good news.

Here's the bad. If we don't see anything from that system the picking might be slim. Here's the superensembles mean centered on day 11.

It spit out 10 dates. of those 10, 70% produced less than one inch during the month. Only 2 gave above normal amounts for the month.

1989 and 1967.

The latest snow in Dec 1989 was dec 13th....after dec 13th there was no snow until march. The date in dec picked was dec 30th so essentially extending dec 30 into Jan that date would also give no snow so essentially 80 percent suggest less than an inch will fall at dca during dec.

1988 had a whopping 1.2 inches of snow (the second largest amount). 1967 ended up with 6.3 inches centered close to the mean date. However, even though it was an analog picked by the computer, it's northeast Atlantic and southeast were markedly different than the map shown above. It's hard for me to see why it was chosen as an analog.

It still looks like it will be hard to get snow unless we get something like what the 06Z gfs is showing. With this type pattern, that's about as good a track as you can hope for.

[winterymix]

Since they both show a la nina like look with a potent positive nao, I'll fall for them until the end of dec, then I have no clue.

These maps look like the complete opposite of the 500 mb composite pattern

that you post frequently, Wes, to remind us of the patterns that have historically

given DC 8 inch snows.

Not complaining, I get get some outdoor running in even during early evening

in this mild pattern.

[Ji]

snow lovers nightmare and we are looking at a snow event a few days after this post was written.Weather is funny

[Fozz]

snow lovers nightmare and we are looking at a snow event a few days after this post was written.Weather is funny

Doesn't change the fact that this is a horrible pattern.

[Ji]

Doesn't change the fact that this is a horrible pattern.

one of the worst patterns i have ever seen but somehow it may produce snow. Gives hope for the rest of the winter

[usedtobe]

one of the worst patterns i have ever seen but somehow it may produce snow. Gives hope for the rest of the winter

Didn't pan out, the horrendous pattern won unless you care about a few flakes right at the end. Don Sutherland posted elsewhere that the AO is likely to stay positive for the foreseeable future. The stratospheric temps at high latitudes reamin well below normal and the ensembles are still forecasting a positive ao through the run which argues that he is right. I'm still on the less snow than average for December as the pattern holds. What would really lead to a terrible period would be the epo going positive with a positive ao. The models are certainly hinting at that. We need a fluke in this pattern or else we get cold shots and then it warms up and rains.

[Ian]

Hopefully we can knock out a big chunk of January at the least. Winter blows.

[mattie g]

Hopefully we can knock out a big chunk of January at the least. Winter blows.

HECS are cool, though.

I just fear a torch through January, then a cold March. That would be miserable.

[Bob Chill]

This may have been touched on somewhere already but one thing that caught my eye was how rare november +ao of at least +1.0 or higher is (at least since 1950 anyway). This past november finsished off @ +1.459. Thee are only 3 other Novembers with +1 or greater.

1978 2.470

1993 1.002

1994 1.779

1994 was the only year that had a positive AO in December too. Dec 1994 came in at .894. This Dec may actually break the monthy record (since 1950) of 2.282 set back in 2006.

A +ao of +1.0 or greater is much more common in December than November. It's happened 11 times in the last 60 years. One thing I don't like about those 11 times is only one year (1979) had a -ao in Jan.

The one thing that stuck in my mind from looking at this data is that a strong +ao in Dec pretty much carries though the following Jan.

[marked8]

Joe Lundberg said this depressing bit a little while ago:

but the sense I get is that with absolutely NO sign of any kind of blocking downstream over the North Atlantic, and a high probability for upper-level ridging east of Hawaii, we ought to see some sort of trough in the West or over the Rockies, which should also correspond to some signs of upper-level ridging farther east over the Gulf of Mexico and Florida. And if that happens, there will likely be another surge of pretty mild air coming up through the South and into the East late next week or early next weekend.

[mattie g]

SE Ridge = better fishing and golf weather on Hilton Head at Christmas.

[usedtobe]

The Euro ens mean has a rather warm look on day 10 but the GefS ens mean looks on the cool side. I don't see this as a pattern change. Both models have below normal heights over greenland giving this a strong positive nao look. Even if the gfs pacific pattern pans out we'll still have trouble getting snow unless some supervort digs southward far enough to track south of us, that's not likely. The euro ridge is still in the pacific putting the trough in the west. I guess I'm saying my call still looks pretty safe for the next 10 days. This still remains a crappy pattern.

Euro

gefs

I don't know which is more correct. much might depend on what the MJO does, whether it marches east or dies in the circle of death as some models are forecasting. The euro ensemble mean is probably a little more skillful but it seems to have liked retrograding the ridge more than it actually has.

[H2O]

Good stuff, wes, and I agree. There are a lot more people on the social media who are calling this the real deal pattern change. I still think that until the Atlantic gets its act together it will be very difficult to get a white rain event here anytime soon.

[usedtobe]

Good stuff, wes, and I agree. There are a lot more people on the social media who are calling this the real deal pattern change. I still think that until the Atlantic gets its act together it will be very difficult to get a white rain event here anytime soon.

I looked at the D+11 super ens mean analogs and 2 of the 10 did have snow in the period.....1 inch and 2.5 inches at DCA. The others didn't have snow for 11 or more days after the D+11 centered mean so it's not impossible to get snow by the end of the month but the odds still are against it.

[nw baltimore wx]

I looked at the D+11 super ens mean analogs and 2 of the 10 did have snow in the period.....1 inch and 2.5 inches at DCA. The others didn't have snow for 11 or more days after the D+11 centered mean so it's not impossible to get snow by the end of the month but the odds still are against it.

Although things don't sound good, they also don't sound entirely bleak either. Maybe boring is the word to use? And maybe this slow period is the beginning of a slow transition to something different. Hopefully, that's a better pattern for January, but there's no convincing evidence of that.

By the way, I'm a little late reading it, but I really like the article on CWG regarding snowstorm forecasts going wrong. Good stuff and thanks.

[usedtobe]

Good stuff, wes, and I agree. There are a lot more people on the social media who are calling this the real deal pattern change. I still think that until the Atlantic gets its act together it will be very difficult to get a white rain event here anytime soon.

The ridging in western canada does mean that the first arctic outbreak may occur into the plains and great lakes region and some of that air probably get to us but it will still be trasnitory but may end up being the coldest air so far this year with the air arriving somewhere around xmas. I still think the probably is below normal for snow (an inch or more event) during xmas week but that's a wag. We look to be trended to the higher amplitude nina pattern with a strongly positive nao.

[Deck Pic]

The ridging in western canada does mean that the first arctic outbreak may occur into the plains and great lakes region and some of that air probably get to us but it will still be trasnitory but may end up being the coldest air so far this year with the air arriving somewhere around xmas. I still think the probably is below normal for snow (an inch or more event) during xmas week but that's a wag. We look to be trended to the higher amplitude nina pattern with a strongly positive nao.

Just looked at the 12z Euro and it is advertising a pretty interesting Pacific pattern....but the Atlantic still looks awful and still a nasty PV well to our NW....and of course it is day 10...lol....still, I think being later in December, and a better PAC at least would give us a fighting chance at small events versus what we had, which was almost no chance....I'm not aiming high....but I wouldn't mind a 1-3" event....

[HM]

Just looked at the 12z Euro and it is advertising a pretty interesting Pacific pattern....but the Atlantic still looks awful and still a nasty PV well to our NW....and of course it is day 10...lol....still, I think being later in December, and a better PAC at least would give us a fighting chance at small events versus what we had, which was almost no chance....I'm not aiming high....but I wouldn't mind a 1-3" event....

Matt, I think this cold plunge is legit. The East Pacific Ridge, as Jorge pointed out, has been semi-permanent because of the stratospheric circulation. Let's face it, the North Pacific circulation is not 100% La Niña/-PDO-like with an Aleutian Low. As the waves elongate to more winter-like in length toward xmas, this E PAC ridge will become more PNA. Now, this may not mean -NAO quite yet, but it certainly brings the cold down into America (setting up a more classic La Nina type of temp departure).

Looks like a Midwest low of significance Dec 18-20 and then perhaps an East Coast low Dec 21-24 as the baroclinic zone arrives. Will there be another fast moving coastal before xmas?

[stormman]

HM, We need you to give us some positive hope for january and feb, its been getting very negative on this forum lately with everyone basically cancelling winter. Everyone calling for another 2001-2002

Matt, I think this cold plunge is legit. The East Pacific Ridge, as Jorge pointed out, has been semi-permanent because of the stratospheric circulation. Let's face it, the North Pacific circulation is not 100% La Niña/-PDO-like with an Aleutian Low. As the waves elongate to more winter-like in length toward xmas, this E PAC ridge will become more PNA. Now, this may not mean -NAO quite yet, but it certainly brings the cold down into America (setting up a more classic La Nina type of temp departure).

Looks like a Midwest low of significance Dec 18-20 and then perhaps an East Coast low Dec 21-24 as the baroclinic zone arrives. Will there be another fast moving coastal before xmas?

[Deck Pic]

HM, We need you to give us some positive hope for january and feb, its been getting very negative on this forum lately with everyone basically cancelling winter. Everyone calling for another 2001-2002

go away

[Deck Pic]

Matt, I think this cold plunge is legit. The East Pacific Ridge, as Jorge pointed out, has been semi-permanent because of the stratospheric circulation. Let's face it, the North Pacific circulation is not 100% La Niña/-PDO-like with an Aleutian Low. As the waves elongate to more winter-like in length toward xmas, this E PAC ridge will become more PNA. Now, this may not mean -NAO quite yet, but it certainly brings the cold down into America (setting up a more classic La Nina type of temp departure).

Looks like a Midwest low of significance Dec 18-20 and then perhaps an East Coast low Dec 21-24 as the baroclinic zone arrives. Will there be another fast moving coastal before xmas?

i like the progression into an increasingly better pattern, if not great, coinciding with more favorable climo....Oct 29th f-ucked everyone up....Other than Ji, I don't remember so many people worried about a block in the middle of November.....all the time we have "wasted" has mostly been time that yields very little...Obviously New England is different...it hurts them more to punt 11/15-12/15

[HM]

i like the progression into an increasingly better pattern, if not great, coinciding with more favorable climo....Oct 29th f-ucked everyone up....Other than Ji, I don't remember so many people worried about a block in the middle of November.....all the time we have "wasted" has mostly been time that yields very little...Obviously New England is different...it hurts them more to punt 11/15-12/15

Excellent point. In my view, obviously yours too, this year has always been about January and possibly February (like any year really). The favorable jet positioning and introduction of Arctic Air 12/20 is the first step. I still think January has some pretty good snow events for the Mid-Atlantic, starting with something near New Years (obviously not a major / KU event given the NAO state).

[usedtobe]

go away

I wonder who everyone is. Not you, not me, certainly not Mitchnick.

[mattie g]

I wonder who everyone is. Not you, not me, certainly not Mitchnick.

I suppose realism about a bad pattern can be construed as negativity, although everyone is still trying to find the positives despite the obvious crap we've been dealt so far.

[Bob Chill]

I think most of us in the MA are realistic about the upcoming winter. No one ever expected it to be a good one. Going in, we were all just hoping to hit climo or slightly above climo snow.

The one thing that appears to have caught most of us by surprise is a warm Dec. I think the majority expected Dec to be cold and have a -nao but not looking to be in the cards. That's ok though. Warmer than average overall appears a bit more likely now but I think most of us think we do ok in the snow department. Even if the good pattern(s) this winter are brief, they'll probably be productive. Heck, last winter has a rockin NAO and we struggled the entire winter.

[Jebman]

What is going to be positively agonizing about this winter is going to be nights like tonight getting down to 20 degrees, and cold days like Sunday barely eking out 40 degrees, only to see a return flow of warm mild air followed by heavy rainfall, then more bone chilling cold (without snow of course).

This nightmare will stretch on unrelieved for at least another three interminable months.

Already I am crying for spring.

La Nina with a -pdo and a monster heat ridge is hell on earth. I hate this place.

[NeedaSnowday]

What is going to be positively agonizing about this winter is going to be nights like tonight getting down to 20 degrees, and cold days like Sunday barely eking out 40 degrees, only to see a return flow of warm mild air followed by heavy rainfall, then more bone chilling cold (without snow of course).

This nightmare will stretch on unrelieved for at least another three interminable months.

Already I am crying for spring.

La Nina with a -pdo and a monster heat ridge is hell on earth. I hate this place.

I must admit I got a chuckle out of this post... <sigh> but the reality of what you said isnt so funny... I'd rather read about Jebwalks

[usedtobe]

Last night's runs took away some of the cross polar look that the day run had and the models look like there could be quite warm anomalies at around 216 hrs (dec 21).

Of course there is always a chance that the models have the pattern wrong but with both the gefs and euro putting a trough in the west there should be a warmer than normal stretch coming prior to the next cool down and the euro and euro ensemble mean suggest maybe not a torch but we could have a day well above normal.

The 240 hr still has a nice strong positive ao and nao and also has sort of a positive epo look with low heights over Ak and high heights north of Hawaii.

That agrees with the ncep ens mean forecast which switches from what has been a chilly pattern. The ESRL ensembles are more a mixed bag but they usually are not quite as good (I think but have no stats to prove it).

The bottom line is we're probably going to see more warmer than normal temps prior to the next cool down and the period jsut prior to xmas is not looking quite as nice as on yesterday's runs. Does that mean xmas is lost for snow, no, but the pattern needs to improve on the next several model runs. This is probalby my last long post until Tuesday when I plan on doing another CWG piece.

[Jebman]

It speaks VOLUMES about this winter here in the southern Mid Atlantic when we had that front with all the torrential, flooding rainfall a few days ago, replete with STRONG north winds, cold air advection featuring northerly wind gusts to over 40 MPH!!!! that brought the ambient air temps at the 2 meter level to 34 degrees yet FAILED to change us over to a BRIEF burst of snow or even effin SLEET for goodness sake!!!!!!!!!!!!!!!!

Yeah.

It sucks HUGE hairy goat balls to live where I live. I hate this place. I hate my life. I wish I had never even been born. This forum would a lot better off, and posts would be readable for a change. This is going to be a long terrible winter in DC. It is going to be freezing cold, so cold that I'm not even going to be able to jebwalk, yet we will break 300 year old records for rainfall and have floods throughout the low sun period thanks to a relentless heat ridge straight out of hell and a pacific jet high on steroids and drunk with Red Bull and meth.

This has got to be the WORST place on earth to live.

Unless you get a hardon from bein' fricken' MISERABLE

[CoastalWx]

It speaks VOLUMES about this winter here in the southern Mid Atlantic when we had that front with all the torrential, flooding rainfall a few days ago, replete with STRONG north winds, cold air advection featuring northerly wind gusts to over 40 MPH!!!! that brought the ambient air temps at the 2 meter level to 34 degrees yet FAILED to change us over to a BRIEF burst of snow or even effin SLEET for goodness sake!!!!!!!!!!!!!!!!

Yeah.

It sucks HUGE hairy goat balls to live where I live. I hate this place. I hate my life. I wish I had never even been born. This forum would a lot better off, and posts would be readable for a change. This is going to be a long terrible winter in DC. It is going to be freezing cold, so cold that I'm not even going to be able to jebwalk, yet we will break 300 year old records for rainfall and have floods throughout the low sun period thanks to a relentless heat ridge straight out of hell and a pacific jet high on steroids and drunk with Red Bull and meth.

This has got to be the WORST place on earth to live.

Unless you get a hardon from bein' fricken' MISERABLE

Is this the MA version of snowNH??