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KA WINTER OUTLOOK


WEATHER53

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I think I omitted an important part of what I was trying to say. The MA lives and dies by storm track more than precip anomalies. We get about 12" of precip a winter and we consider ourselves lucky if just 2 of those inches fall as snow. But looking at those precip anomalies implies to me (and I hope I'm wrong) that the southern storm track is not nearly as prevalent during weak ninos. Pull a composite for mod ninos and it shows a very different story. That's more than what I was getting at. Weak nino's don't seem to correlate nearly as well to a southern storm track as mod ones. 

 

 

I looked at DC snowfall history for all of the years posted above and again, it's just not that encouraging at all. Only 1 winter (77-78) cracked 20" until you go all the way back to 39-40 (25"). 77-78 as saved by a big march so the DJF period only had 14". 1904 was the only blockbuster year and I find it hard to have any confidence in data that old. 

 

Persistence in the MA since 1940 has been to have crappy snowfall totals during weak nino events. It's hard to bet against that at this lead. Our winter here will likely be decided by the AO/NAO behavior moreso than enso imo. Maybe that will become more clear once we enter Nov. 

 

If we get into weak but borderline moderate territory, would that have any influence?

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If we get into weak but borderline moderate territory, would that have any influence?

 

It would mostly likely have some impact on storm track and precip anomalies but that is no guaranty on snowfall. 91-92 & 94-95 were stinkers in that department. Overall, a min of 1.1 and max of 1.8 trimonthly seems to be the magic range for snowfall in our yards but small datasets come with plenty of caveats. I highly doubt we will have a trimonthly of 1.1+. I wouldn't bet a nickel on it. 

 

This composite looks quite a bit different than the weak events. 

 

post-2035-0-47001800-1411419047_thumb.jp

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I remember HM posting a couple of years ago regarding KA. His thought was that KA's "forecast method" was most likely to be successful when global weather patterns are relatively stable. Given the transition from a La Niña /cold PDO to something clearly different this upcoming winter, his forecast may be off. Last year , he went above normal temps and normal to below normal snow for DCA.

MDstorm

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One of the things that kinda sucks about weak or warm neutral enso winters is that they tend to not be wet here very often and even though we associate warm enso to an active southern storm track, the anomalies tell a different story. The deep south, SE and MA were pretty dry during the winters of 79-80, 04-05, 06-07. Of course this is a small dataset and bad practice to draw conclusions on, but it's hard to ignore. I don't really see much evidence showing that weak nino's are favorable for AN precip through the deep south, SE and MA. 

 

This is a composite of warm neutral and weak events since 1950. 

 

 

attachicon.gifweakensoprecip.JPG

 

 

Taking the warm neutrals out looks even worse for the SE. 

 

 

I'm starting to think that hitting AN climo snow this year would be another fluke and that enso may not be as big a driver (in our area) of AN precip and/or snow as some people think (unless we pull off a 4th q comback to mod status). I still don't really know what to think about this winter. It's awfully muddy right now imo.  

But if you look at the years with anomalies of +0.2 to +0.8 there are 11 years and 4 of them ended up with above normal snow.  1979-1980, 1987-1988, 1953-1954, 1977-1978 so not all weak years are stinkers.  We got close to having really big years in 1979-1980 and 1977-1978. 

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But if you look at the years with anomalies of +0.2 to +0.8 there are 11 years and 4 of them ended up with above normal snow.  1979-1980, 1987-1988, 1953-1954, 1977-1978 so not all weak years are stinkers.  We got close to having really big years in 1979-1980 and 1977-1978. 

 

I wonder how the warming of the SST baseline has affected all this...something like 53-54 would have peaked at a +0.3 or so against the current norms...a winter like 09-10 would have had a tri-monthly peak of around +1.9 if it was in the 1950s...I am guessing it is the anomaly that matters most...2004 and 2006 acted like weak ninos, even if they would have been stronger 50 years ago.

 

http://www.cpc.ncep.noaa.gov/data/indices/ersst3b.nino.mth.81-10.ascii

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I wonder how the warming of the SST baseline has affected all this...something like 53-54 would have peaked at a +0.3 or so against the current norms...a winter like 09-10 would have had a tri-monthly peak of around +1.9 if it was in the 1950s...I am guessing it is the anomaly that matters most...2004 and 2006 acted like weak ninos, even if they would have been stronger 50 years ago.

 

http://www.cpc.ncep.noaa.gov/data/indices/ersst3b.nino.mth.81-10.ascii

Good question,  don't know the answer just as it is hard to know whether the baseline from the previous year may have had an impact.  1987-1988 was a horrid year if you take away November so you have to wonder whether there was some hangover from the previous nino year.  That said, I think it more likely that the Veteran's day storm was just a fluke but a fluke can result in a decent year.

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But if you look at the years with anomalies of +0.2 to +0.8 there are 11 years and 4 of them ended up with above normal snow.  1979-1980, 1987-1988, 1953-1954, 1977-1978 so not all weak years are stinkers.  We got close to having really big years in 1979-1980 and 1977-1978. 

 

It's interesting that the majority of them "behaved" like a nino and the overall NH height pattern isn't really all that different when you compare the decent/bad against each other. If you take out Dec in the decent set you get a much closer look to the not so good ones. The Aleutian low stands out on all composites. Thankfully, we are seeing that in the means right now. May be a sign of a more typical nino with that feature if it persists. 

 

post-2035-0-83768300-1412172697_thumb.gi

 

 

post-2035-0-87416100-1412172707_thumb.gi

 

 

post-2035-0-17073700-1412172718_thumb.gi

 

 

We're a small piece of real estate anyways. Just because we stunk some years doesn't mean that we couldn't do much better in the same setup. Longwave patterns can't really predict individual storms. Sometimes things don't work out in decent patterns. Things probably don't work out more often then they do in decent patterns. 

 

The only thing about 87-88 that I don't like is the freak November storm. Take that one out and the winter was pretty blah. 

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Good question,  don't know the answer just as it is hard to know whether the baseline from the previous year may have had an impact.  1987-1988 was a horrid year if you take away November so you have to wonder whether there was some hangover from the previous nino year.  That said, I think it more likely that the Veteran's day storm was just a fluke but a fluke can result in a decent year.

 

 

I didn't mind 87-88 because January was so good...the storm on the 7th was a nice one, and a cold one....and snow/ice stuck around for quite a while since the month was so cold..I had several snow days and good sledding...I think we had a few additional smaller events in January...february and december sucked...

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Good question,  don't know the answer just as it is hard to know whether the baseline from the previous year may have had an impact.  1987-1988 was a horrid year if you take away November so you have to wonder whether there was some hangover from the previous nino year.  That said, I think it more likely that the Veteran's day storm was just a fluke but a fluke can result in a decent year.

 

Wes, it's been a while! I did a "Walker Cell Analysis" using post-79' CHI for Sep-Dec (but supplemented with other things like omega/surface wind/pressure) to rank neutral/Nino years. 1987-88 had the strongest WC by far since 1979. Strong in this case means, the cell was more "Nina-like" than the rest. It seems like the atmosphere was giving us a clue about its eventual demise. 2009-10 also had a stronger WC. The early 90s and the two strongest Nino years of course had the weakest cells, overall.

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It's interesting that the majority of them "behaved" like a nino and the overall NH height pattern isn't really all that different when you compare the decent/bad against each other. If you take out Dec in the decent set you get a much closer look to the not so good ones. The Aleutian low stands out on all composites. Thankfully, we are seeing that in the means right now. May be a sign of a more typical nino with that feature if it persists. 

 

attachicon.gifweak ninos aob climo.GIF

 

 

attachicon.gifweak ninos below climo.GIF

 

 

attachicon.gifweak nino jan feb decent.GIF

 

 

We're a small piece of real estate anyways. Just because we stunk some years doesn't mean that we couldn't do much better in the same setup. Longwave patterns can't really predict individual storms. Sometimes things don't work out in decent patterns. Things probably don't work out more often then they do in decent patterns. 

 

The only thing about 87-88 that I don't like is the freak November storm. Take that one out and the winter was pretty blah. 

 

The variations in the STJ and its behavior near/toward us might be worth looking at the differenes too since the NH heights are comparable. A lot of great snow events in close-Nino/weak Nino years are like the mod-strong Nino storms...overrunning moisture bombs.

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The variations in the STJ and its behavior near/toward us might be worth looking at the differenes too since the NH heights are comparable. A lot of great snow events in close-Nino/weak Nino years are like the mod-strong Nino storms...overrunning moisture bombs.

 

problem is we are capped down here in a weak/borderline event...places well north and west can do ok, but we don't get big storms...6" is about our cap...maybe 8" in a rare situation...these overrunners thump us and then change over or we dryslot...if we aren't going to get a formidable nino (and it looks like we won't), I'd rather have a negative neutral/borderline nina...weak nino events can be productive but 10-15" is probably the best range for an outlook..so slightly above median...

 

None of our big events (below) happened in weak/borderline nino events...we've had maybe 1-2 events over 6"...that's it

 

Feb 58 - Mod Nino

Jan 66 - Mod nino

Feb 67 - negative neutral

Pd1 - Negative neutral

Feb 83 - Strong Nino

Jan/Feb 87 - Mod Nino

Jan 96 - weak Nina

PD2 - Mod Nino

Feb 2006 - weak nina

09-10 - Mod Nino

Feb 14 - negative neutral

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problem is we are capped down here in a weak/borderline event...places well north and west can do ok, but we don't get big storms...6" is about our cap...maybe 8" in a rare situation...these overrunners thump us and then change over or we dryslot...if we aren't going to get a formidable nino (and it looks like we won't), I'd rather have a negative neutral/borderline nina...weak nino events can be productive but 10-15" is probably the best range for an outlook..so slightly above median...

 

None of our big events (below) happened in weak/borderline nino events...we've had maybe 1-2 events over 6"...that's it

 

Feb 58 - Mod Nino

Jan 66 - Mod nino

Feb 67 - negative neutral

Pd1 - Negative neutral

Feb 83 - Strong Nino

Jan/Feb 87 - Mod Nino

Jan 96 - weak Nina

PD2 - Mod Nino

Feb 2006 - weak nina

09-10 - Mod Nino

Feb 14 - negative neutral

 

If issues truly exist with changing background normals, perhaps you should do a comparison analysis with the MEI instead of the traditional metrics for ENSO.

 

My own observations so far this year show times when the atmosphere is extremely Nino (very weak Walker Cell, narrow Hadley Cell, westerly flows into 30N, Atlantic shear/tropical activity in Pacific), despite the struggling 3.4 number.

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If issues truly exist with changing background normals, perhaps you should do a comparison analysis with the MEI instead of the traditional metrics for ENSO.

 

My own observations so far this year show times when the atmosphere is extremely Nino (very weak Walker Cell, narrow Hadley Cell, westerly flows into 30N, Atlantic shear/tropical activity in Pacific), despite the struggling 3.4 number.

 

yeah..I'll check out MEI...been a while...I don't doubt we can get a big storm in a weak event..it just hasn't happened..maybe we are due..I'm moving away from relying too much on statistical analyses..my approach to this winter outlook is evolving and being reworked...I have to get this one right...more fail in weaker events below that crushed somebody, including the coastal plain in several

 

Lindsay - screwed

Late Feb 69 - interior

March 93 - interior (though close for the cities)

Feb/March 94 - screwed or ice or interior

Feb 95 - interior

Dec 2003 - interior

January 2005 - epic screwjob

Feb 2007 - interior

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If issues truly exist with changing background normals, perhaps you should do a comparison analysis with the MEI instead of the traditional metrics for ENSO.

 

My own observations so far this year show times when the atmosphere is extremely Nino (very weak Walker Cell, narrow Hadley Cell, westerly flows into 30N, Atlantic shear/tropical activity in Pacific), despite the struggling 3.4 number.

That's certainly my observations.  I'm a little confused why 2009-2010 would have had a stronger WC and why with a stronger one,  the winter season was so active. 

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That's certainly my observations.  I'm a little confused why 2009-2010 would have had a stronger WC and why with a stronger one,  the winter season was so active. 

 

It wasn't as active as it seemed...certainly not like this year...the big KU in December and the big stretch  from 1/30 - 2/10, and that was it ...the rest of the events were tiny....we were virtually shut out from 12/20 to 1/30 and then winter ended for us after 2/10...I do realize you aren't talking specifically about DC and there was a big event on 2/26 that screwed us

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That's certainly my observations.  I'm a little confused why 2009-2010 would have had a stronger WC and why with a stronger one,  the winter season was so active. 

 

Keep in mind, I calculated it for SOND only. I wanted a lead signal for winter and wanted to capture a strengthening to peaking event. It is also a relative thing, too, where I am only comparing to other neutral/nino years.

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Keep in mind, I calculated it for SOND only. I wanted a lead signal for winter and wanted to capture a strengthening to peaking event. It is also a relative thing, too, where I am only comparing to other neutral/nino years.

 

2009-10 during DJFM had more divergence over Dateline than the rest...surprise, surprise. ;)

post-176-0-00119500-1412177063_thumb.jpg

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As an example, here is the CHI comparisons for 1994 (left) and 2009 (right) for Sep-Dec. Despite both being carelessly called "modoki," 1994's Walker Cell was extremely weakened (like many were in the 90s). 2009, on the other hand, was much stronger with plenty of W PAC lift (ultimately it progressed to Dateline in winter).

post-176-0-12949700-1412177439_thumb.jpg

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The better longer-tem (since development in early spring) MEI progression analogs are extreme with results right now:

 

58-59: 4.9"

80-81: 4.5"

91-92: 6.6"

94-95: 10.1"

12-13: 3.1"

 

....OR....

 

57-58: 40.4"

02-03: 40.3"

09-10: 56.1"

 

The first group had many that started rapidly declining around this time of year. The new Aug/Sep number will be telling. 91-92 was of course Pinatubo-altered.

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