December 2019 Med/Long Range Disco

[Bob Chill]

6 minutes ago, frd said:

I don't recall the exact specifics, ( coffee still kicking in )  but reading over a post at 33 someone noted a similar evolution that did happen and triggered a negative  NAO which was one factor responsible for the Jan 2016 miracle that trended from a rain event many days prior to your victory of the winter.  Is that all true ?  

Excuse my 3rd grade paint skills but this visual is decent. The scand ridge signal is just now showing up but starting to become more prominent. We want it to push all the way into GL and that will force lower heights/confluence/compressed flow in the 50/50 region. That can suppress storm track and allow slower exits of cold highs to our north. 

 

 

I don't remember exactly what happened in 2016 but iirc that was a bootleg/transient west based -NAO block. It could have been at the hands of the scand ridge. I just can't remember. No matter how it shakes out, scand ridging poking poleward is always a net plus in these parts. 

[frd]

 

If, this "colder" risk does indeed verify, it would go counter the recent warm-ups after 12/20 and potentially make many snow weenies happy.

The storm threats look to continue, the more there are the higher the odds we eventually score especially if what Bob mentioned above continues to progress as well. Maybe we eventually progress to a Northern Mid Atlantic SECS pattern. 

 

[Bob Chill]

@frd

Here's the lead up to the Jan 16 event. It was just a perfectly placed/large west based -NAO. It formed at the perfect time but it was not at the hands of scand ridging. 

[jaydreb]

31 minutes ago, Bob Chill said:

@frd

Here's the lead up to the Jan 16 event. It was just a perfectly placed/large west based -NAO. It formed at the perfect time but it was not at the hands of scand ridging. 

Just curious, how do you make these composites?  Is there a website?

[Bob Chill]

Just now, jaydreb said:

Just curious, how do you make these composites?  Is there a website?

There's a couple. Here's the one where you can pull single days (or short periods):

https://www.esrl.noaa.gov/psd/data/composites/day/

Here's the monthly/seasonal composites:

https://www.esrl.noaa.gov/psd/cgi-bin/data/composites/printpage.pl

[snowmagnet]

What did the 13th-15th look like on the overnight models?  I know it’s 7-8 days away, but....

[jaydreb]

9 minutes ago, Bob Chill said:

There's a couple. Here's the one where you can pull single days (or short periods):

https://www.esrl.noaa.gov/psd/data/composites/day/

Here's the monthly/seasonal composites:

https://www.esrl.noaa.gov/psd/cgi-bin/data/composites/printpage.pl

Cool.  Thanks Bob.  

 

[psuhoffman]

58 minutes ago, frd said:

I don't recall the exact specifics, ( coffee still kicking in )  but reading over a post at 33 someone noted a similar evolution that did happen and triggered a negative  NAO which was one factor responsible for the Jan 2016 miracle that trended from a rain event many days prior to your victory of the winter.  Is that all true ?  

The blocking that helped with 2016 did mostly originate from across the pole.  The Kara block was a major player.  I am not sure it was every really rain, but the models did show a very marginal temp setup and some runs had a mix from 10-12 days out. From about day 9 in they started to lock in though.  

[LP08]

Icon looks to be moving closer to the follow up wave for next week.

[LP08]

GFS has "snow" into the cities by 6z Wednesday.  Front has a more E-W orientation.

[Baltimorewx]

1 minute ago, LP08 said:

GFS has "snow" into the cities by 6z Wednesday.  Front has a more E-W orientation.

We know how that plays out though...may we see some white rain? possible. But the chances of accum are slim to none in that kind of set up in my opinion. NW winds usually dry things out enough before cold enough

[WxUSAF]

Gfs soundings on TT look really weird. Somethings not right when the maps say it’s snowing. 20C dewpoint depression at 750mb with precip??

[Steve25]

Does anyone recall a time when a situation like next Tuesday/Wednesday actually worked out to provide accumulating snow? I'm sure it's happened, just can't think of any specific events. 

[CAPE]

5 minutes ago, Baltimorewx said:

We know how that plays out though...may we see some white rain? possible. But the chances of accum are slim to none in that kind of set up in my opinion. NW winds usually dry things out enough before cold enough

I thought that nice little shortwave along the Texas Gulf Coast might get involved with the NS, but it gets left behind. Unless we see a legit sw moving along the boundary, I agree this is just typical model depiction of cold chasing rain at range.

[Bob Chill]

2 minutes ago, Steve25 said:

Does anyone recall a time when a situation like next Tuesday/Wednesday actually worked out to provide accumulating snow? I'm sure it's happened, just can't think of any specific events. 

2013/14 had like 6 of them. Maybe more. 2014/15 had another streak of them. These are "staple events" in a progressive -EPO regime. The margins are razor thin and the bust risk is there right up until close to game time but don't view this "event" as anything "unusual" or "not possible". 

[LP08]

1 minute ago, C.A.P.E. said:

I thought that nice little shortwave along the Texas Gulf Coast might get involved with the NS, but it gets left behind. Unless we see a legit sw moving along the boundary, I agree this is just typical model depiction of cold chasing rain at range.

Yeah, I saw that as well as a better front orientation before checking the surface.  Hence why I put "Snow" in quotes.  It's more than likely the "precip depiction" maps doing their normal thing showing snow once the front clears.

[Steve25]

1 minute ago, Bob Chill said:

2013/14 had like 6 of them. Maybe more. 2014/15 has another streak of them. These are "staple events" in a progressive -EPO regime. The margins are razor thin and the bust risk is there right up until close to game time but don't view this event as anything "unusual" or "not possible". 

Thanks! I just have an awful memory. 

[WxUSAF]

More and more looks like northern stream shenanigans want to mess up next weekend. Also means things are really complicated and we won’t have anything certain for awhile.

[psuhoffman]

1 hour ago, Bob Chill said:

@frd

Here's the lead up to the Jan 16 event. It was just a perfectly placed/large west based -NAO. It formed at the perfect time but it was not at the hands of scand ridging. 

The immediate lead up was classic but I was referring to the pattern progression weeks before.  There bears some similarities to this coming situation.

We were coming off of this torchmass crap pattern.  Couldnt get any worse.  

But the eventual flip started with scand ridging that built over the top.

Because all of north america was void of any cold at all we then wasted about 10 days of a pretty good pattern and a couple perfect track storms. Even up here I remember getting heavy rain with some slush bombs mixed in from a perfect track coastal in January and was like come on man!  We finally built up just enough mid latitude cold under the blocking to get that one big hit. But the high latitudes stayed favorable the rest of winter and we had another 3-4 storms that without the super nino wrecking the mid latitude temperature profile across the CONUS would have been snow.  

But we can hope for a similar type of progression up top and with a less hostile temperature profile this time.  

[Bob Chill]

9 minutes ago, Steve25 said:

Thanks! I just have an awful memory. 

Here's the event list for my yard in 2013/14:

11/27: T
12/08: 1.5" snow .25" sleet .20 Ice
12/10: 2.0" 
12/14: .25" 
01/02: 4.5"
01/21: 6.75"
01/28: .5"
02/09: .5"
02/13: 16.25" (13 front / 3.25 ull)
02/18: 1.0"
02/25: 1.25"

02/26: 2.50"

03/03: 5.50"

03/16: 9.50"

03/25: 3.00" (worst measuring event by me. Two closest trained spotters had 3.6 & 3.8)

03/30: .7"

55.70" 

 

Nearly every event on this list is either a clipper type deal or a wave on a front except for 2/13 as that was an organized coastal. Most of the events over 2" were frontal waves with the notables being 12/8, 12/10, 1/2, 1/21, 3/3, 3/16 (not sure about this one). The whole season was mostly progressive waves on fronts. For reasons we'll never fully understand, our area had a bullseye on it from start to finish. I'm not expecting a seasonal repeat of that year again before I'm dead. lol

[Wonderdog]

That lp in the nw has come out of no where on this run. Lots of moving parts and the storm has sped up it appears.

[WxUSAF]

13 minutes ago, LP08 said:

Yeah, I saw that as well as a better front orientation before checking the surface.  Hence why I put "Snow" in quotes.  It's more than likely the "precip depiction" maps doing their normal thing showing snow once the front clears.

No, gfs shows snow for us. Issues with the soundings and maps not jiving pending. How much accumulates is another question. For now let’s focus on getting that front through with enough energy hanging back to generate some more precip.

[psuhoffman]

10 minutes ago, WxUSAF said:

More and more looks like northern stream shenanigans want to mess up next weekend. Also means things are really complicated and we won’t have anything certain for awhile.

A lot of time to change but yea it's going the wrong way.  I am starting to get interested in the look after that.  And this is certainly an interesting development.  Yea its just an op run but its only 8-9 days out not day 15 and we know things can flip pretty suddenly without much warning up top sometimes.  But this look is certainly "interesting".  

[Chris78]

19 minutes ago, C.A.P.E. said:

I thought that nice little shortwave along the Texas Gulf Coast might get involved with the NS, but it gets left behind. Unless we see a legit sw moving along the boundary, I agree this is just typical model depiction of cold chasing rain at range.

I think more seperation would be helpful.  Whatever ripple forms along the front is too close the the main energy. Another 12 hours slower would be good.

[Bob Chill]

1 minute ago, Wonderdog said:

That lp in the nw has come out of no where on this run. Lots of moving parts and the storm has sped up it appears.

That's the tricky part about split/progressive flow. Two streams are burping shortwaves into fast flow. How each piece plays together is rarely if ever nailed down until inside of 4 days and even that is a stretch.

What if the northern stream wave ends up being faster and drags the boundary south as the lagging southern shortwave makes a move? What if the northern stream wave doesn't exist at all? Don't overthink ops outside of 4 days unless a block forms. This is a terrible pattern for medium/long range skill. It's bringing back memories of the 2013-15 stretch where our medium/long range chances vanished regularly but things popped up seemingly out of nowhere in the short/medium range. 

[psuhoffman]

obvious disclaimer that this is all for "fun" but come on its holiday season we can dream.

I could envision that energy crashing out west in this look arriving just in time for a merry Christmas!

[WxUSAF]

@Bob Chill and @psuhoffman agree strongly with both your last posts. Looks like we’ll have chances after next weekend if it doesn’t work out, but the fast flow doesn’t encourage long track storms.

[psuhoffman]

@mappy

incoming...

its just 24 hours too fast with the timing...plenty of time to correct

[Steve25]

13 minutes ago, Bob Chill said:

Here's the event list for my yard in 2013/14:

11/27: T
12/08: 1.5" snow .25" sleet .20 Ice
12/10: 2.0" 
12/14: .25" 
01/02: 4.5"
01/21: 6.75"
01/28: .5"
02/09: .5"
02/13: 16.25" (13 front / 3.25 ull)
02/18: 1.0"
02/25: 1.25"

02/26: 2.50"

03/03: 5.50"

03/16: 9.50"

03/25: 3.00" (worst measuring event by me. Two closest trained spotters had 3.6 & 3.8)

03/30: .7"

55.70" 

 

Nearly every event on this list is either a clipper type deal or a wave on a front except for 2/13 as that was an organized coastal. Most of the events over 2" we're frontal waves with the notables being 12/8, 12/10, 1/2, 1/21, 3/3, 3/16 (not sure about this one). The whole season was mostly progressive waves on fronts. For reasons we'll never fully understand, our area had a bullseye on it from start to finish. I'm not expecting a seasonal repeat of that year again before I'm dead. lol

Awesome information! Now I'm dying to go back and see radar from some of those events but I can't seem to find any ways to get that. I have a source that I can see the precipitation, but it doesn't show precipitation type or temperatures. I swear Wunderground used to provide that, but they don't seem to anymore. 

[WxUSAF]

GGEM’s got the frontal wave snow and a clipper a day later too! Wes jackpot! Hoffman fringed