December Medium/Long Range Discussion

[Heisy]

CMC ensembles agree with the OP, alright back to work!

[stormy]

7 minutes ago, Wentzadelphia said:

12z JMA for ji of course. The LP doesn’t come from the best spot, but the signal is there. HP showing up in SE Canada is of course a big deal for us.

That 1040 HP just north of Ogdensburg is definitely a "big deal" if the LP tracks through southeast Va..

[psuhoffman]

MJO plots are all over the place because there are multiple waves sending conflicting signals...but it seems day 10-16 the wave out near the dateline becomes more prominent on the GEFS.  That would be helpful tropical forcing for a change.  The mean plot shows phase 6 because a wave back near the MC and the one near the dateline are battling each other in the means.  But if the forcing near the dateline is dominant that may explain the change to a more favorable look.  Or it's just a coincidence.  

[frd]

 

Interesting to see how this evolves in the time period  of interest near mid-month.  Continued signs of HL  blocking persist.

 

 

 

 

[H2O]

3 minutes ago, stormy said:

That 1040 HP just north of Ogdensburg is definitely a "big deal" if the LP tracks through southeast Va..

I prefer Massena but its splitting hairs

[frd]

@psuhoffman Liking the AAM tendencies and what they portend.

I  feel we can get a rather robust - NAO in the weeks ahead.  Might coincide with an improving Pac and a growing cold air source to our NW. 

 

 

 

 

[JakkelWx]

1 hour ago, psuhoffman said:

that's legit...not some bootleg transient ridge...straight -NAO...no chaser.   And it really starts to build in the short range not some unicorn long range fantasy.  

At least a moderately strong -AO is already building in now so it'll greatly increase the chances of a stable NAO block verifying.

[MJO812]

Nice signal on the eps

[Ralph Wiggum]

Approaching the make or break period IMHO. Past few winters (or lack of), when model mahem appeared in December the final result sort of dictated the base state the rest of the winter. I know things can turn on a dime at any point but generally we establish things in the period approaching. If we can actually get some of these ull tellie looks to pan out and not be a tease, we should be in businesses this season with ample chances. We know what happened with these teaser looks past years. Fingers crossed.

[Maestrobjwa]

57 minutes ago, psuhoffman said:

I wouldn't automatically attribute anything to just one factor without a lot more research and data.  It could be the solar minimum.  Or maybe its something else and its just a coincidence.  Or maybe the solar minimum is just a part of the equation and there are other factors contributing also.  There are way too many variables to just pin it on one thing.  If it was that easy forecasting wouldn't be so difficult.  

Yeah I can understand that perspective...on the other hand, IF the -NAO is true, I find it mighty strange how we haven't had winter one for almost a decade (basically since the 2009-10 with only maybe one other case)...and then all of the sudden we get one after a minimum.

[frd]

This look towards the end of December has changed for the better during the past 5 day period. Have not seen today's though. 

 

 

[Ji]

thats the other thing with fantasy snow....we can never get it to show up for 2 runs in a row

 

[MJO812]

2 minutes ago, Ji said:

thats the other thing with fantasy snow....we can never get it to show up for 2 runs in a row

 

Check the eps

[CAPE]

1 hour ago, LP08 said:

Xmas Eve storm?  LOCK IT UP almost @CAPE avatar lol

 

December 2009!

2020 redux, Nina style? 

[psuhoffman]

14 minutes ago, Maestrobjwa said:

Yeah I can understand that perspective...on the other hand, IF the -NAO is true, I find it mighty strange how we haven't had winter one for almost a decade (basically since the 2009-10 with only maybe one other case)...and then all of the sudden we get one after a minimum.

We had a period of NAO blocking in 2013. Didn’t do is much good. Also a pretty good period in 2016 but it was cancelled in the means by extreme +NAO periods. Also March 2018. Blocking has been rare lately yes. But there are enough examples not to automatically assume its solar. I’m not saying it’s not. Just that we can’t say for sure. 

[Maestrobjwa]

1 hour ago, psuhoffman said:

If you get just enough blocking it sets off a chain reaction that reconfigured a Nina look into a workable one. What I found was we actually do ok in a Nina if we have a cooperative AO/NAO. Problem is that’s not all that common. Nina tropical forcing tends to favor a +NAM state more often then not. But in cases where we do get help up top it can snow in a Nina. 

Two questions:

1) What other examples outside of 1995-96 where we did okay in a nina because of what you just mentioned?

2) Speaking of 95/96...was some record -AO/-NAO the reason why it worked?

[Eskimo Joe]

Eric Webb is a pretty big warminsta:

 

[WxUSAF]

34 minutes ago, MJO812 said:

Nice signal on the eps

Details or pics?

[WxUSAF]

42 minutes ago, MJO812 said:

Nice signal on the eps

 

6 minutes ago, WxUSAF said:

Details or pics?

Lol it’s a Miller B signal. Congrats Bahstan. 
 

Maybe there are some nice hits in the individual members, not sure. 

[Paleocene]

Not bad

[nj2va]

15 minutes ago, Paleocene said:

Not bad

 

Would that be a clipper/NS dominated pattern if that verifies verbatim?

[WxUSAF]

Summarizing the Eps snow maps for the midweek storm next week: 3 ggem like monsters, 5-6 modest events. A few suppressed solutions which I don’t mind at D7. More chances interior unsurprisingly. 
 

Looking at MSLP, can’t tell if the Miller B look is from 2 camps (one cutter and one coastal) or if these are doublebarreled lows which would scorch our BL temps. 

[Ji]

i feel like we keep driving the ball to the 35 yard line and keep missing 52 yard field goals

[WxUSAF]

Just now, Ji said:

i feel like we keep driving the ball to the 35 yard line and keep missing 52 yard field goals

Thankfully still got 7 minutes left in the first quarter. 

[DTWXRISK]

48 minutes ago, WxUSAF said:

 

Lol it’s a Miller B signal. Congrats Bahstan. 
 

Maybe there are some nice hits in the individual members, not sure. 

  YES  DEF MILLER B

 

[DTWXRISK]

58 minutes ago, Eskimo Joe said:

Eric Webb is a pretty big warminsta:

 

  HUGE DEVELOPMENT IF  THIS VERIFIES 

[clskinsfan]

 

36 minutes ago, Paleocene said:

Not bad

GEFS for the same timeframe. Look awfully similar from a week out.

[psuhoffman]

21 minutes ago, Maestrobjwa said:

Two questions:

1) What other examples outside of 1995-96 where we did okay in a nina because of what you just mentioned?

2) Speaking of 95/96...was some record -AO/-NAO the reason why it worked?

Well 1995/6 was the only example where we had a blockbuster winter on the whole...because it was the only nina where we had persistent blocking all winter long.   So you have to judge things in proportion...if we only get a 10 day blocking period you can't expect to get 50" in that 10 day period.  But if you get 10" of snow during that 10 day period...that was a productive period.  But if you end up with only that 10" all winter the winter as a whole seems bad, but that blocking period wasn't the reason.  The problem in a nina is we tend to do REALLY bad without blocking.  So the whole rest of winter is often a barren wasteland outside those blocking episodes.  Especially in a moderate or stronger nina.  We can sometimes get lucky with some smaller snows in a weaker nina without blocking.  

So with that out of the way...limiting this to more recent 1980 onward ninas for Baltimore...and looking at periods of prolonged blocking...we had some very transient blocks that lead to an isolated minor event over the years...but lets look at just longer periods of blocking during moderate or stronger ninas.  Links to the H5

January 1985 there was a major blocking period in January that lead to 2 snowfalls 2.5" and 3.7".  This one you could argue underproduced...it was a pretty darn good looking pattern that only produced 2 storms and pretty minor.  But it wasn't totally wasted it did snow twice during the 4 weeks of major blocking.  But this was probably the biggest underproducing blocking period of the list I looked at.  It was brutally cold at times though.  

https://imgur.com/Mwy5pwN

the blocking broke down in February and a more typical nina pattern took over and that was winter over.  

March 99 really produced with several snow events in our area over a 2 week period.  

https://imgur.com/GVgexww

We wasted most of the rest of that winter with a +NAO

January 2000: this was probably the biggest over performer.  We only had about a 10 day favorable blocking pattern that whole winter and we hit big time with 3 snowfall events across the area and 1 HECS.  

https://imgur.com/OexbcZJ

December/January 2010-11:  This one underperformed.  A lot of bad luck.  Somehow missed a miller a that took a weird curve and had a messy phase that screwed us over.  We did get 2 snowfalls in January out of it, one advisory and one warning level event.  So it wasn't a totally wasted period but we did miss out on the one HECS level event during this period...hit on that and it goes from slightly disappointing to epic.  Oh well.   Also...we tend to waste NAO blocking in December more then any other month...if you get blocking you would rather it later then earlier in winter.  

https://imgur.com/N8eM9FS

Some notable weaker nina blocking periods that produced recently

February 2006:  lead to that one big storm...the pac ridge was REALLY flexing though and limited our ability to get anything more out of that period. 

March 2018: shame that block didn't come a month earlier but we did get one minor and one significant snowfall out of it even in March.  

The problem in those years wasn't that it didnt snow when there was blocking...it was mostly that it didnt snow much at all the rest of the winter when there wasn't blocking.

As for 1996...There were 2 periods of extreme blocking that set off what happened.  The first was early in the winter.  It was actually fading by the time we got the HECS in January but the pattern was set in motion.  We got several minor snows in December during the height of the block.

This in Dec set everything in motion. 

But the second half of January the blocking faded and this was the only period where a typical nina pattern took hold and lead to our torch/melt/flood period. 

Then the blocking reloaded in late January/February and set off the second half of winter.  That blocking would reload several times the rest of winter into April.  

If we were to get a repeat of that level of blocking that repeated multiple times all winter like 1996 we would likely end up with a very good winter again, nina or not.  Not saying we necessarily do as well as 1996..there might have been some luck in there too...but we would snow quite a bit given the number of chances we would get with that kind of blocking all winter long (with the exception of 2 weeks in January).  

 

 

[WxUSAF]

Eps and GEFS have -3SD AO next week. That alone is a snow signal. Fingers crossed we can take advantage of a good long wave pattern.

[psuhoffman]

10 minutes ago, WxUSAF said:

Eps and GEFS have -3SD AO next week. That alone is a snow signal. Fingers crossed we can take advantage of a good long wave pattern.

Or it could go down like the EPS control and the reaper will be busy. Suppressed, miller b split, huge suppressed storm just to our south, and the grand finale a perfect track perfect h5 huge rainstorm on Xmas eve as the cold gets too stale.