January 2013 mid-long range disco thread

[mitchnick]

Give it another week or two. It's not last year. We don't have a la nina and NAO and AO have had some decent negative spats.

 

DC Can get there seasonal average in one or two storms, not that hard if the pattern turns good for a week in late January and again sometime in mid February. But if  in 10 days models are still hugging the SE ridge for another 10 days, it's time to find a new hobby.

 

about sums it up; little did I know on 2/11/10 that then was the time to start a new hobby

[QVectorman]

Good disco from Buffalo regarding late Jan. for eastern US.

 

000FXUS61 KBUF 080253AFDBUFAREA FORECAST DISCUSSIONNATIONAL WEATHER SERVICE BUFFALO NY953 PM EST MON JAN 7 2013

 

THE SECOND PATTERN CHANGE WILL BEGIN TO SHOW ITS CARDS BY THE MIDDLEOF THE MONTH. A MAJOR SUDDEN STRATOSPHERIC WARMING EVENT IS UNDERWAYAND NEARING COMPLETION. SUDDEN STRATOSPHERIC WARMING EVENTS AREFAVORED TO OCCUR DURING AN EASTERLY PHASE OF THE QUASI-BIENNIALOSCILLATION /QBO/...WHICH IS THE PHASE THE STRATOSPHERE IS IN THISWINTER. THE SUDDEN STRATOSPHERIC WARMING CAUSES A DRAMATICWEAKENING...AND SOMETIMES ENTIRE BREAKDOWN OF THE STRATOSPHERICPOLAR VORTEX...AND A GREAT WEAKENING OR EVEN REVERSAL OF THESTRATOSPHERIC POLAR NIGHT JET. THE GFS FORECASTS THIS TO OCCUR OVERTHE NEXT WEEK AT THE 2MB LEVEL.THE RESULT OF ALL OF THIS IS THE GENERATION OF STRONG HIGH LATITUDEBLOCKING AS THE DRAMATIC CHANGES IN THE STRATOSPHERE FEED DOWN INTOTHE TROPOSPHERE. HIGH LATITUDE BLOCKING FORCES THE COLDEST AIR SOUTHOUT OF THE HIGH ARCTIC AND TOWARDS THE MID LATITUDES...AND ALSOFAVORS LASTING STRONGLY NEGATIVE EPISODES OF ARCTIC OSCILLATION /AO/AND NORTH ATLANTIC OSCILLATION /NAO/. THIS TYPICALLY BEGINS TO TAKEPLACE 10-15 DAYS AFTER THE SUDDEN STRATOSPHERIC WARMING EVENT. HOWLONG IT LASTS CAN VARY...BUT TYPICALLY THE COLD PATTERN LASTS FOR ATLEAST A FEW WEEKS...AND OCCASIONALLY CAN PERSIST THROUGH THE REST OFWINTER.AS ALL OF THIS IS OCCURRING...THE MJO IS FORECAST BY THE GEFSENSEMBLES TO WEAKEN AND FADE AWAY IN ABOUT 10 DAYS. THE PACIFICNORTH AMERICAN PATTERN /PNA/ IS FORECAST TO REMAIN NEGATIVE OVER THENEXT 10 DAYS...WHICH WILL DIRECT THE FIRST BATCHES OF COLD INTO THEWESTERN AND EVENTUALLY CENTRAL UNITED STATES. GEFS ENSEMBLE MEMBERSSUPPORT A TREND TOWARDS A NEUTRAL OR POSITIVE PNA BY THE MIDDLE OFTHE MONTH...WHICH SHOULD ALLOW THE GROWING COLD TO SPREAD EASTWARD.WHAT ALL OF THIS TECHNICAL JARGON MEANS IS THAT THERE IS MODERATE TOHIGH CONFIDENCE IN A PATTERN CHANGE TOWARDS MUCH COLDER WEATHER FORTHE CENTRAL AND EASTERN UNITED STATES STARTING AROUND THE MIDDLE OFJANUARY...WITH COLD LIKELY PEAKING IN LATE JANUARY INTO EARLYFEBRUARY. THERE IS THE POTENTIAL FOR THE COLDEST AIR WE HAVE SEEN INAT LEAST SEVERAL YEARS DURING THIS PERIOD. WHAT SNOW POTENTIAL THISWILL BRING IS MUCH MORE UNCERTAIN DUE TO UNKNOWN DETAILS WITH SYNOPTIC

[H2O]

Thanks for that. It is an awesome explanation of what to expect and or look for as we head to the end of the month. I certainly hope it occurs.

[Wonderdog]

Thanks for that. It is an awesome explanation of what to expect and or look for as we head to the end of the month. I certainly hope it occurs.

 

0z GFS Model has been hinting at an east coast storm around the 17th for a few runs now. EURO has a storm around then on the east coast also (at least up the coast anyway).

[ORH_wxman]

yes..I think for a DC specific forecast getting involved with too many indices creates a mess...I am not as sure about other locations...I do think other indices help round out an outlook and some are quite important as well....I think the conventional wisdom that neutral ENSO is not as much of a player is in error....

 

The ENSO dependency in DC is enormous compared to other regions on the E Coast when it comes to snowfall. It really is basically in the bullseye for that. The Carolinas have less ENSO dependency than DC. Then once you get up into New England, there is almost no ENSO signal at all.

 

The combo of being far enough north in snow climo that one single moderate snow event won't make a season and the longitude being a little further west probably helps make that bullseye for ENSO dependency.  

 

I think the idea about neutral ENSO not being much of a player pertains more to the high latitude pattern rather than snowfall for DC specifically. Neutral ENSO is a big deal for DC because neutral ENSO generally means you have a lack of a STJ, and DC is highly dependent on that for big snowfall winters. Its more about what neutral ENSO lacks, rather than what it provides when it comes to snowfall in that region.

[Deck Pic]

The ENSO dependency in DC is enormous compared to other regions on the E Coast when it comes to snowfall. It really is basically in the bullseye for that. The Carolinas have less ENSO dependency than DC. Then once you get up into New England, there is almost no ENSO signal at all.

 

The combo of being far enough north in snow climo that one single moderate snow event won't make a season and the longitude being a little further west probably helps make that bullseye for ENSO dependency.  

 

I think the idea about neutral ENSO not being much of a player pertains more to the high latitude pattern rather than snowfall for DC specifically. Neutral ENSO is a big deal for DC because neutral ENSO generally means you have a lack of a STJ, and DC is highly dependent on that for big snowfall winters. Its more about what neutral ENSO lacks, rather than what it provides when it comes to snowfall in that region.

 

yes...I think there is a common fallacy and I have bought into it before as well that when ENSO is neutral it gets overwhelmed by other factors and is less of a player....which logically doesnt really make sense...a gigantic body of water that is a significant global factor isn't suddenly going to be muted or neutered because it is 27C instead of 25 or 29....Once it became apparent that NINO would be super weak or nonexistent the die was cast here...the fact that we are currently in a NINA state (3.4 is freezing) hasn't helped matters...either way, having the NINA stink from the last 2 winters especially in a -PDO state kills us....to get big snow winters here we need either a Nino or the remnants of one....95-96 was an exception but it is pretty clear that 8 years of Nino or neutral preceding it kept it from acting very Nina-like..fortunately there is a pretty good chance there will be a Nino next winter

[Ji]

check out the 1064 High on the GFS

 

[mitchnick]

check out the 1064 High on the GFS

 

 

 

while we're at 40 degrees and rain....yeah, it's great 

[Ji]

while we're at 40 degrees and rain....yeah, it's great 

 

ya that part sucks but if if you want cold..go to NW canada!

[BristowWx]

ya that part sucks but if if you want cold..go to NW canada!

what about in the 200hrs-300hrs timeframe? Doesn't look that bad.

[RIC_WX]

Also, reading what the Richmond area folks have been saying for years now, something has definitely happened with their snow climatology that's substantial and decades-long. Without getting into a climate change debate, I do want to note that Richmond's decline might be significant for the DC area considering their metropolitan area is our neighbor to the south. 2009-2010 couldn't possibly have been less than average for even Richmond, but they way underperformed compared to our area. Is it getting harder to stay all snow in the lower Mid-Atlantic? If so, is that trend creeping north?  

 

Richmond had around 50% of the snow DC measured in 2009-10.  However, the metro area still recorded 200%-300% of what would typically be considered normal.  Not sure I would agree Richmond underperformed much relative to averages.

 

At the peak of seasonal inflection (think height of winter or summer) there is little variation in weather between the Richmond and DC area.  However, on the fringes of any season, there can be substantial differences in temperature as per climo...fronts tend to set up and sometimes stall across VA leaving northern areas relatively colder / southern areas warmer.  This is most observable in the period from early spring to early summer.  For snowfall specifically, the best recent example came in 2007, where DC had many late season snow events that eluded the Richmond are entirely.

 

It's somewhat less common for a snow event to impact DC and Richmond equally.  Typically, DC is on the southern most end of events focused further north the same way Richmond gets in on the northern most end of Carolina focused events that miss DC and points north entirely.  See December 2010 for recent examples here, where Richmond outperformed DC for snow, and DC was too far south to get in meaningfully on the events focused on the NYC area north.

 

In practice, DC gets in on the southern fringe of snow events far more often than the Richmond area gets in on northern fringe events, hence DC's greater overall snow climate.

[Deck Pic]

ya that part sucks but if if you want cold..go to NW canada!

 

the blocking pattern by the end of the run is sick...not sure if it is being rushed or not....the good storm track will probably lag it by 1-2 weeks...2/5 - 3/5?...that is a good month to capitalize..

[BristowWx]

the blocking pattern by the end of the run is sick...not sure if it is being rushed or not....the good storm track will probably lag it by 1-2 weeks...2/5 - 3/5?...that is a good month to capitalize..

312 hr is the first time I have seen the third blue -20C 850 line cross into the area...I know it won't happen but sure is nice to see it...can't remember the last time I saw it...

[Bob Chill]

There is a pretty damn big wall to our north and as you click the panels you can see the ridging poking into gl and also through AK towards the poles. THAT is a major squeeze and would push a ton of cold air into at least canada. 

 

Flow doesn't have much amplification late in the run but who cares. Just give me a general 500 setup like this and we can worry about the details later. I still think our first shot at area wide accum snow is going to be a clipper event. NS only. But maybe a potent little vort with cold air at its disposal. I was hoping that there would be hints at something leftover at the tail of the front next week that could ride up the boundary but the setup is just not there at all. Rainy frontal passage and some really cold/dry winds for a couple days and then maybe something dives out of canada? I'm reaching here....

 

[mitchnick]

312 hr is the first time I have seen the third blue -20C 850 line cross into the area...I know it won't happen but sure is nice to see it...can't remember the last time I saw it...

 

I can; earlier this year but it never happened

I feel confident it will be cold 2 weeks from today, but that doesn't guarantee snowfall/chances as we all know

[yoda]

It does seem that the 12z run dumps some serious cold (well, compared to what we have seen here the past 2 winters temp-wise) for a few days... but I agree with Zwyts that it would appear that the GFS is signaling a good pattern by the end of the month... hopefully its not one of those usual things where once we get closer the GFS taketh away

[ORH_wxman]

yes...I think there is a common fallacy and I have bought into it before as well that when ENSO is neutral it gets overwhelmed by other factors and is less of a player....which logically doesnt really make sense...a gigantic body of water that is a significant global factor isn't suddenly going to be muted or neutered because it is 27C instead of 25 or 29....Once it became apparent that NINO would be super weak or nonexistent the die was cast here...the fact that we are currently in a NINA state (3.4 is freezing) hasn't helped matters...either way, having the NINA stink from the last 2 winters especially in a -PDO state kills us....to get big snow winters here we need either a Nino or the remnants of one....95-96 was an exception but it is pretty clear that 8 years of Nino or neutral preceding it kept it from acting very Nina-like..fortunately there is a pretty good chance there will be a Nino next winter

 

Agreed. '95-'96 also had a decent STJ in February that winter which certainly was out of character for a typical Nina. Perhaps the +PDO regime and lasting effects from the previous several years of warm ENSO were a factor, I'm not sure. Combine that with happening to hit one out of the park on a split flow polar jet pattern in early January, and you get a historic winter.

 

But even if you whiffed on the blizzard, it still would have been a solid winter in DC with that STJ-infused February..and it carried over into early March...esp for the suburbs.

[Deck Pic]

Agreed. '95-'96 also had a decent STJ in February that winter which certainly was out of character for a typical Nina. Perhaps the +PDO regime and lasting effects from the previous several years of warm ENSO were a factor, I'm not sure. Combine that with happening to hit one out of the park on a split flow polar jet pattern in early January, and you get a historic winter.

 

But even if you whiffed on the blizzard, it still would have been a solid winter in DC with that STJ-infused February..and it carried over into early March...esp for the suburbs.

 

I think a blocking pattern at the end of January even with a -PNA will be much more fruitful than one in DEC....I don't know if it is wavelengths or climo or both....but a -NAO in DEC is not great down here with a bad PAC

[gymengineer]

Richmond had around 50% of the snow DC measured in 2009-10.  However, the metro area still recorded 200%-300% of what would typically be considered normal.  Not sure I would agree Richmond underperformed much relative to averages.

 

At the peak of seasonal inflection (think height of winter or summer) there is little variation in weather between the Richmond and DC area.  However, on the fringes of any season, there can be substantial differences in temperature as per climo...fronts tend to set up and sometimes stall across VA leaving northern areas relatively colder / southern areas warmer.  This is most observable in the period from early spring to early summer.  For snowfall specifically, the best recent example came in 2007, where DC had many late season snow events that eluded the Richmond are entirely.

 

It's somewhat less common for a snow event to impact DC and Richmond equally.  Typically, DC is on the southern most end of events focused further north the same way Richmond gets in on the northern most end of Carolina focused events that miss DC and points north entirely.  See December 2010 for recent examples here, where Richmond outperformed DC for snow, and DC was too far south to get in meaningfully on the events focused on the NYC area north.

 

In practice, DC gets in on the southern fringe of snow events far more often than the Richmond area gets in on northern fringe events, hence DC's greater overall snow climate.

You all had another brutal stretch from 96/97 through 98/99 where the DC area was ok for one of those seasons.

 

Yes, 09/10 was well above average for Richmond, but not well over 300% seasonal snowfall (closer to 400% at DCA).You're right that underperforming was the wrong term.

 

The main point is that your 30-year avg snowfall has dropped by 10-15% (almost two inches) because of the most recent two decades, while the average actually went up a bit for DC. While we got two top five seasons with one of them being the snowiest ever in the 1981-2010 period, along with one more top ten season, Richmond didn't do as well compared to their own records. You had two top ten seasons (95/96 and 82/83), none in the top five. But you also experienced also six (!!) out of the top ten smallest totals ever recorded for Richmond (compared to 4 for DC).  

 

I'm not trying to suggest DC is "better" or anything like that.. I'm just saying that for whatever reason, random or not, Richmond has not seen a top-3 type snow season in the recent decades while it also had to suffer through a whole bunch of historically awful snow seasons. And I wonder if DC is next for that-- so instead of us always talking about "Feast or famine," we would change to talk about "big dinner vs. famine."  

[WinterWxLuvr]

312 hr is the first time I have seen the third blue -20C 850 line cross into the area...I know it won't happen but sure is nice to see it...can't remember the last time I saw it...

 

I doubt the -20 850 line and snow would be dance partners in our area.  I'll take the -5 line and snow.

[mitchnick]

I know, I know, 10 day Euro BUT.....looks interesting with plenty of cold

we just need that trough to open back up

could still yield a snow to mix/rain

http://www.ecmwf.int/products/forecasts/d/charts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!240!North%20America!pop!od!oper!public_plots!2013010812!!/

 

precip maps are freebies today

this is the 228 hr map (for some reason, 240 map is blank)

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_24h_cumulated_precipitations!228!North%20America!msl!pop!od!oper!w_mslrain!2013010812!!/

[usedtobe]

I know, I know, 10 day Euro BUT.....looks interesting with plenty of cold

we just need that trough to open back up

could still yield a snow to mix/rain

http://www.ecmwf.int/products/forecasts/d/charts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!240!North%20America!pop!od!oper!public_plots!2013010812!!/

 

precip maps are freebies today

this is the 228 hr map (for some reason, 240 map is blank)

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_24h_cumulated_precipitations!228!North%20America!msl!pop!od!oper!w_mslrain!2013010812!!/

Mitch if that were to verify it would be a clear snow to snow. Unfortunately getting heights that low south of Nova Scotia is rare sO i suspect it is an outlier. However, the GEFS ensemble mean from last night was showing blocking in the same region (Greenland/Nova Scotia) so the pattern is for sure looking more interesting. If the Euro still looks like that on a day 5 forecast, I'd start being excited.

[H2O]

I know, I know, 10 day Euro BUT.....looks interesting with plenty of cold

we just need that trough to open back up

could still yield a snow to mix/rain

http://www.ecmwf.int/products/forecasts/d/charts/medium/deterministic/msl_uv850_z500!Geopotential%20500%20hPa%20and%20Temperature%20at%20850%20hPa!240!North%20America!pop!od!oper!public_plots!2013010812!!/

 

precip maps are freebies today

this is the 228 hr map (for some reason, 240 map is blank)

http://www.ecmwf.int/samples/d/inspect/catalog/samplers/banner/mean_sea_level_pressure_and_24h_cumulated_precipitations!228!North%20America!msl!pop!od!oper!w_mslrain!2013010812!!/

 

the 228 precip map looks like it would really be for the 240 based on low location.  weird.

[NJwinter23]

You got it.  Some of these guys are like doctors writing prescriptions, They seek for their message to be clouded in language (or in this case methodology) that is moslty understandable and applicable to them alone.

 

Over and over again we get that "it's just a tool".  Tool for what?-incongruity.

Put it simple and decades of observation confirm it.  Get some strong high pressure over of within 1-200 miles of Mongolia and that is the cold air mass, for whatever reason, that has a high propensity to end up over the mid atlantic.  Show me that, I can get excited. Show me how a+b+c+d=e is going to happen in 10-15 days and if all of it does happen then we can get cold then I am unexicted and there is a good reason for that-Analgos far trump indexes.

 

Sounds like you have it all figured out..       3 jeers

[RIC_WX]

You all had another brutal stretch from 96/97 through 98/99 where the DC area was ok for one of those seasons.

 

Yes, 09/10 was well above average for Richmond, but not well over 300% seasonal snowfall (closer to 400% at DCA).You're right that underperforming was the wrong term.

 

The main point is that your 30-year avg snowfall has dropped by 10-15% (almost two inches) because of the most recent two decades, while the average actually went up a bit for DC. While we got two top five seasons with one of them being the snowiest ever in the 1981-2010 period, along with one more top ten season, Richmond didn't do as well compared to their own records. You had two top ten seasons (95/96 and 82/83), none in the top five. But you also experienced also six (!!) out of the top ten smallest totals ever recorded for Richmond (compared to 4 for DC).  

 

I'm not trying to suggest DC is "better" or anything like that.. I'm just saying that for whatever reason, random or not, Richmond has not seen a top-3 type snow season in the recent decades while it also had to suffer through a whole bunch of historically awful snow seasons. And I wonder if DC is next for that-- so instead of us always talking about "Feast or famine," we would change to talk about "big dinner vs. famine."  

Maybe not for the RIC airport.  The 1995-96 and 2009-10 seasons were still epic.  OFP (OFP to RIC is like JYO to DCA) recorded north of 50" in 95-96.  I measured between 14"-15" for the January 30, 2010 event, surface temps of 18*F during the duration of the storm...yet just SE of RIC there was sleet mixing in at the height of the storm, suppressing airport totals considerably.

 

From the late 1950's through late 1980's, RIC was closer to 15" annually.  Since 1990, more like 10" and maybe a little less as you point out.  Which period represents the anomaly?

 

The same N and W phenomenon that impacts DC is ever present in Richmond too.  March 1993 was almost no snow at the RIC airport, a mixed bag for the immediate metro area, and NWS documented 9" for central Powhatan county, 30 nautical miles W of RIC airport.

 

The blockbuster events for DC - think 2/2003, 2/2010...almost always mix for RIC...except for the late season events which will be primarily rain wire to wire.  I don't think this is a change, pretty much always been this way, at least for the 32 years I lived in Richmond and was paying attention.  2/2003 was forecast the day of to be 24"+ for RIC and it was 4" IP.  So, if someone could explain why big snow for DC and points north always means significant IP for RIC, maybe we would have a better explanation for their lousy snowfall climo.

[mitchnick]

Mitch if that were to verify it would be a clear snow to snow. Unfortunately getting heights that low south of Nova Scotia is rare sO i suspect it is an outlier. However, the GEFS ensemble mean from last night was showing blocking in the same region (Greenland/Nova Scotia) so the pattern is for sure looking more interesting. If the Euro still looks like that on a day 5 forecast, I'd start being excited.

 

wooo-hoooo!!!

 

be nice if the ensembles showed something similar just for the excitement factor, albeit subdued

 

as an aside, I wish those d@mn Europeans would put US state borders on their freebie maps (because I have to complain about something)

[Bob Chill]

wooo-hoooo!!!

 

be nice if the ensembles showed something similar just for the excitement factor, albeit subdued

 

as an aside, I wish those d@mn Europeans would put US state borders on their freebie maps (because I have to complain about something)

 

lol- mitch? seriously? state borders? how many times have you stared at a map of the us just on eastern and amwx alone?

 

GFS ens mean looks fine. I really like the squeeze between ridging up through AK and also into GL. Really helps me believe in the pv asserting itself southward and kinda getting stuck with a nice blocking look. I suppose the next thing to freak out on is lack of precip but hey, it hasn't been cold here since early 2011. Gotta start somewhere.  

[SNO]

I am liking the January 24-27 time period this year for a SNO storm.

[WinterWxLuvr]

wooo-hoooo!!!

 

be nice if the ensembles showed something similar just for the excitement factor, albeit subdued

 

as an aside, I wish those d@mn Europeans would put US state borders on their freebie maps (because I have to complain about something)

 

The Euro day 10 setup looks like the late Jan 2010 setup, just a little east of what that one was.

[stormtracker]

wooo-hoooo!!!

 

be nice if the ensembles showed something similar just for the excitement factor, albeit subdued

 

as an aside, I wish those d@mn Europeans would put US state borders on their freebie maps (because I have to complain about something)

 

You'll get your snowstorm by next weekend.  I'm in Vegas.