December pattern/forecast thread

[radiator]

There was a New England temperature map that I used to refer to as fronts approached from the west, but I have forgotten where I used to get that from.

Any suggestions? 

I'm currently located in the Litchfield Hills in NW CT, and I don't think that it climbed much above 40 here today - would like to follow the progression of temps downward as the big chill sweeps in.

 

 

 

 

[Typhoon Tip]

15 minutes ago, radiator said:

There was a New England temperature map that I used to refer to as fronts approached from the west, but I have forgotten where I used to get that from.

Any suggestions? 

I'm currently located in the Litchfield Hills in NW CT, and I don't think that it climbed much above 40 here today - would like to follow the progression of temps downward as the big chill sweeps in.

 

 

 

 

try this ... it's unofficial.. .http://www.pdfamily.com/weather/mesomap.htm

you could probably do well enough if you just go to google and type in "meso temperature analaysis" or the something like that. 

[weathafella]

Through 12/17:

BOS:  -2.8F

ORH: -3.0F

BDL: -1.8F

PVD: -2.5F

 

 

[Great Snow 1717]

The front has made it to Methuen. The wind has picked up considerably in the last few minutes.

 

And on other note, Cosgrove remains less than optimistic regarding winter along the East Coast.

[Great Snow 1717]

13 minutes ago, weathafella said:

Through 12/17:

BOS:  -2.8F

ORH: -3.0F

BDL: -1.8F

PVD: -2.5F

 

 

I wouldn't be the least bit surprised if all 4 of those locations end up being close to normal or slightly above normal by the end of the month.

[weathafella]

4 minutes ago, Great Snow 1717 said:

I wouldn't be the least bit surprised if all 4 of those locations end up being close to normal or slightly above normal by the end of the month.

It will take a lot.  Today will be muted by 11:59P lows.  The next 2-3 days probably are well below.  It depends on how well we torch but we have 1/3 of the month to erase decent departures.  Even with a hostile pattern there may well be some much below days all the way to the end of the month.

[bobbutts]

Had what must have been the front come through about 45 mins ago with dark skies and gusty winds.. Temp down to 42 now from 45 at that point.

[Hoth]

10 minutes ago, bobbutts said:

Had what must have been the front come through about 45 mins ago with dark skies and gusty winds.. Temp down to 42 now from 45 at that point.

That describes my experience in CT to a T. 

[Typhoon Tip]

temp drop has been decent here... 

53 to 41 across the last hour alone.  we actually had house creek gusts and very loud turbine sounds when that sucker came through Ayer. 

[512high]

Gosh your right on winds, 43F, average winds, 13mph, has a gust 28mph, windchill now 36F, lost a lot of snow,

[radiator]

2 hours ago, Typhoon Tip said:

try this ... it's unofficial.. .http://www.pdfamily.com/weather/mesomap.htm

you could probably do well enough if you just go to google and type in "meso temperature analaysis" or the something like that. 

That looks like the one that I remember, thanks!

 

[CapturedNature]

29 minutes ago, radiator said:

That looks like the one that I remember, thanks!

You can also try this:

http://www.wrh.noaa.gov/map/?&zoom=8&scroll_zoom=true&center=42.08599350447723,-72.08129882812499&basemap=OpenStreetMap&boundaries=true,false,false&obs=true&obs_type=weather&elements=temp,wind,gust&obs_popup=false&obs_density=1

It also gives you winds & direction and you can zoom in for additional stations and pan the map for additional areas.

[40/70 Benchmark]

My idea of a near normal December doesn't look too bad.

[Damage In Tolland]

[Isotherm]

15 minutes ago, 40/70 Benchmark said:

My idea of a near normal December doesn't look too bad.

 

That's what I had as well; liking where we stand at this juncture insofar at the forecast. The last week of December could be quite mild overall w/ lower than normal geopotential heights in all the "wrong" domains hemispherically. Still think Jan/Feb are generally above normal temps, but stormy overall with frequent chances in the interior and occasional opportunities further south/along the coast. The pattern is very hostile for the coast through early January, and will likely improve somewhat thereafter (never a great to excellent pattern though). As I said yesterday, I think the possibility of a protracted -NAO/AO period is contingent upon significant stratospheric alterations. 

[40/70 Benchmark]

14 minutes ago, Isotherm said:

 

That's what I had as well; liking where we stand at this juncture insofar at the forecast. The last week of December could be quite mild overall w/ lower than normal geopotential heights in all the "wrong" domains hemispherically. Still think Jan/Feb are generally above normal temps, but stormy overall with frequent chances in the interior and occasional opportunities further south/along the coast. The pattern is very hostile for the coast through early January, and will likely improve somewhat thereafter (never a great to excellent pattern though). As I said yesterday, I think the possibility of a protracted -NAO/AO period is contingent upon significant stratospheric alterations. 

March stands out as a potential period of NAO assist from what I have looked at (maybe latter Feb?); I think January will see some PAC help, and while it should not be overly cold, as the season will not, it should NOT be boring.

I think Feb may blow, though...before the NAO kicks in.

[Isotherm]

3 hours ago, 40/70 Benchmark said:

March stands out as a potential period of NAO assist from what I have looked at (maybe latter Feb?); I think January will see some PAC help, and while it should not be overly cold, as the season will not, it should NOT be boring.

I think Feb may blow, though...before the NAO kicks in.

 

Things are pretty much going as planned on the NAO/AO fronts thus far from my point of view. Precursor signals I examined were suggestive of a hostile to very hostile NAO and neutral to positive AO in the means. Certainly, not looking good for Dr. Cohen's SAI right now, although it is still early. 

Going forward, we see rapid intensification of 10hpa zonal winds with contemporaneous cooling of temperatures to record/near record levels in the upper levels of the stratosphere. This all implicates a tight / symmetrical vortex, almost insurmountably strong like last winter. However, there should be some wave-2 attacks down the road (2-3 weeks), but I don't think they'll be sufficiently potent to induce anything more than perturbation / elongation. Pacific chi 200hpa will largely remain unfavorable for high latitude blocking as well. We may achieve interludes of dateline poleward ridging, but I'm skeptical those interludes will be quite protracted. Will have to monitor potential rossby trains and wave breaks. We will enter a largely low AAM regime which is also generally unfavorable for wave-1/2 amplification on the Pacific side. Right now, in the near term, the best opportunity for a pattern shake-up is likely contingent upon MJO/forcing progression. In the longer term, the stratosphere will likely be the primary determinant of significant NAM alterations [which, at this juncture, I'm not optimistic about, given precursor and current background conditions).  

I actually think Feb might hold better potential for the coast than Jan insofar as -NAO potential. If we can achieve a stratospheric shake-up, it would typically begin to occur in early February if this year paralleled its analogs in terms of vortex strength (at the same time, I wouldn't be surprised if the AO/NAO remained positive through the entire winter).  Strongly positive NAO/AO's in late December tend to persist in the means for January. As I said, interior New England can still do fine, but I'm focusing my discussion mostly for the I-95 corridor. With the Pacific as is, we'd need Arctic/Atl cooperation in some form. A more eastward displaced poleward Pacific ridge can work w/o the Atlantic, but the chances of that occurring are rather low in my opinion.

[SnowGoose69]

4 hours ago, Isotherm said:

 

Things are pretty much going as planned on the NAO/AO fronts thus far from my point of view. Precursor signals I examined were suggestive of a hostile to very hostile NAO and neutral to positive AO in the means. Certainly, not looking good for Dr. Cohen's SAI right now, although it is still early. 

Going forward, we see rapid intensification of 10hpa zonal winds with contemporaneous cooling of temperatures to record/near record levels in the upper levels of the stratosphere. This all implicates a tight / symmetrical vortex, almost insurmountably strong like last winter. However, there should be some wave-2 attacks down the road (2-3 weeks), but I don't think they'll be sufficiently potent to induce anything more than perturbation / elongation. Pacific chi 200hpa will largely remain unfavorable for high latitude blocking as well. We may achieve interludes of dateline poleward ridging, but I'm skeptical those interludes will be quite protracted. Will have to monitor potential rossby trains and wave breaks. We will enter a largely low AAM regime which is also generally unfavorable for wave-1/2 amplification on the Pacific side. Right now, in the near term, the best opportunity for a pattern shake-up is likely contingent upon MJO/forcing progression. In the longer term, the stratosphere will likely be the primary determinant of significant NAM alterations [which, at this juncture, I'm not optimistic about, given precursor and current background conditions).  

I actually think Feb might hold better potential for the coast than Jan insofar as -NAO potential. If we can achieve a stratospheric shake-up, it would typically begin to occur in early February if this year paralleled its analogs in terms of vortex strength (at the same time, I wouldn't be surprised if the AO/NAO remained positive through the entire winter).  Strongly positive NAO/AO's in late December tend to persist in the means for January. As I said, interior New England can still do fine, but I'm focusing my discussion mostly for the I-95 corridor. With the Pacific as is, we'd need Arctic/Atl cooperation in some form. A more eastward displaced poleward Pacific ridge can work w/o the Atlantic, but the chances of that occurring are rather low in my opinion.

There is some reason the AO/NAO have been averaging so positive the last 5 years or so.  I'm no sure what it is or how many more winters it may occur for either.  Its totally not following the Siberian snow rule at all

[qg_omega]

4 hours ago, SnowGoose69 said:

There is some reason the AO/NAO have been averaging so positive the last 5 years or so.  I'm no sure what it is or how many more winters it may occur for either.  Its totally not following the Siberian snow rule at all

Nor is the AO...Much more work needs to be done on Cohen's theory

[Isotherm]

6 hours ago, SnowGoose69 said:

There is some reason the AO/NAO have been averaging so positive the last 5 years or so.  I'm no sure what it is or how many more winters it may occur for either.  Its totally not following the Siberian snow rule at all

 

I have a personal hypothesis which includes the synergistic effect of some key variables. Still testing it but it has seemed to work very well retrospectively. The problem with the snow advance in my opinion is it's too myopic. The polar indices are modulated by a number of factors and I think the most prudent manner to approach it is a weighting type analysis, whereby the factors (either favorable or unfavorable) are examined in totality. It is extremely early but my  guess is that this positive AO/NAO cycle will reverse in the means beginning next year.

 

[40/70 Benchmark]

10 minutes ago, Isotherm said:

 

I have a personal hypothesis which includes the synergistic effect of some key variables. Still testing it but it has seemed to work very well retrospectively. The problem with the snow advance in my opinion is it's too myopic. The polar indices are modulated by a number of factors and I think the most prudent manner to approach it is a weighting type analysis, whereby the factors (either favorable or unfavorable) are examined in totality. It is extremely early but my  guess is that this positive AO/NAO cycle will reverse in the means beginning next year.

 

Totally agreed.

[Typhoon Tip]

1 hour ago, Isotherm said:

 

I have a personal hypothesis which includes the synergistic effect of some key variables. Still testing it but it has seemed to work very well retrospectively. The problem with the snow advance in my opinion is it's too myopic. The polar indices are modulated by a number of factors and I think the most prudent manner to approach it is a weighting type analysis, whereby the factors (either favorable or unfavorable) are examined in totality. It is extremely early but my  guess is that this positive AO/NAO cycle will reverse in the means beginning next year.

 

the pot calling the kettle black here:  all that is code for, there are a lot of factors involved that influence the winter time polar vortex - got it.   

ha ha. J/k...  seriously though, from the literature I encountered in the early days of the cryosphere correlation to modulating the PV (in mid winter) it spoke mostly of the correlation its self and only hypothesized the actual reasons.  

meanwhile, i've often thought that the correlation was more symptomatic than causation - like, there may be a reality where whatever it is that is truly the force(s) in modulating the PV, it's also causing enhanced snow fall in the mid to late autumn.  it could all just be wave harmonics in the atmosphere.. rolling around the higher latitudes and when a couple of time-dependent wave types happen to super-impose, they both cause snow and the PV stuff... 

that said, the hypothesis with cryosphere goes like this:  more snow means more albedo means proficient long night and/or daylight termination cold production in the lower troposphere.  this cold then instantiates a medium wide tendency of downward vertical motion, and then physically ...that requires height rises at mid levels...  blocking erupts, -AO... i haven't heard since weather any of that 'causal' stuff has been researched further. 

as far as the AO/NAO in general... be leery of sudden warm events - i believe (though correct me if i am wrong) the QBO is in phase state that correlates with the occurrence of SSWs... plus, the weak solar correlation too -

[nzucker]

1 hour ago, Isotherm said:

 It is extremely early but my  guess is that this positive AO/NAO cycle will reverse in the means beginning next year.

It's ridiculously early to say this, but I think our best winter might be 2020-21, which is when the solar cycle should bottom out. That solar minimum may induce stronger blocking patterns, resulting in a -NAO/-AO. Global temperatures should also be colder than this year, as we are just starting to lose the heat generated by the 2015 Super El Niño. We will also be into a -AMO at that point. 

The bottom of last solar cycle was in 2008. New England/Upstate NY had a great winter in 2008-2009, with Big Black River, Maine setting a record low at -50F in Jan 2009. We all know 09-10 was an historic winter for the mid-Atlantic/NYC with four huge snowstorms: 12/19, 2/5, 2/10, 2/26. December 2010 also began with record NAO blocking before yielding to the low blocking pattern we've seen prevail since then. The shift essentially occurred as the solar cycle began its upswing in 2011, and since then we have not had sustained NAO blocking. Any high heights over Greenland have been transient, and it was entirely the favorable Pacific that propelled us to excellent winters in 13-14 (58" of snow in Bay Ridge, Brooklyn) and 14-15 (coldest Feb since 1934).

Coincidences? I think not. 

[Isotherm]

55 minutes ago, Typhoon Tip said:

the pot calling the kettle black here:  all that is code for, there are a lot of factors involved that influence the winter time polar vortex - got it.   

ha ha. J/k...  seriously though, from the literature I encountered in the early days of the cryosphere correlation to modulating the PV (in mid winter) it spoke mostly of the correlation its self and only hypothesized the actual reasons.  

meanwhile, i've often thought that the correlation was more symptomatic than causation - like, there may be a reality where whatever it is that is truly the force(s) in modulating the PV, it's also causing enhanced snow fall in the mid to late autumn.  it could all just be wave harmonics in the atmosphere.. rolling around the higher latitudes and when a couple of time-dependent wave types happen to super-impose, they both cause snow and the PV stuff... 

that said, the hypothesis with cryosphere goes like this:  more snow means more albedo means proficient long night and/or daylight termination cold production in the lower troposphere.  this cold then instantiates a medium wide tendency of downward vertical motion, and then physically ...that requires height rises at mid levels...  blocking erupts, -AO... i haven't heard since weather any of that 'causal' stuff has been researched further. 

as far as the AO/NAO in general... be leery of sudden warm events - i believe (though correct me if i am wrong) the QBO is in phase state that correlates with the occurrence of SSWs... plus, the weak solar correlation too -

 

I certainly agree regarding the potential for the autumn snow pattern to be more symptomatic rather than causative. I do think it has an effect, but like I mentioned with the weighting, if one has other important variables (in unfavorable states) which may account for circa 60% of the vortex variability, it would be more difficult for the snow advance to force a favorable NAM. 

[Isotherm]

22 minutes ago, nzucker said:

It's ridiculously early to say this, but I think our best winter might be 2020-21, which is when the solar cycle should bottom out. That solar minimum may induce stronger blocking patterns, resulting in a -NAO/-AO. Global temperatures should also be colder than this year, as we are just starting to lose the heat generated by the 2015 Super El Niño. We will also be into a -AMO at that point. 

The bottom of last solar cycle was in 2008. New England/Upstate NY had a great winter in 2008-2009, with Big Black River, Maine setting a record low at -50F in Jan 2009. We all know 09-10 was an historic winter for the mid-Atlantic/NYC with four huge snowstorms: 12/19, 2/5, 2/10, 2/26. December 2010 also began with record NAO blocking before yielding to the low blocking pattern we've seen prevail since then. The shift essentially occurred as the solar cycle began its upswing in 2011, and since then we have not had sustained NAO blocking. Any high heights over Greenland have been transient, and it was entirely the favorable Pacific that propelled us to excellent winters in 13-14 (58" of snow in Bay Ridge, Brooklyn) and 14-15 (coldest Feb since 1934).

Coincidences? I think not. 

 

Strongly agree. Solar cycle modulation is a major factor in my opinion. 

Dr. Landscheidt researched solar modulation of ENSO quite heavily. I think the sun has more influence than most realize, in both weather and climate.

[nzucker]

Just now, Isotherm said:

 

Strongly agree. Solar cycle modulation is a major factor in my opinion. 

Do you see the potential for a blockbuster winter in 19-20/20-21? Any particular year that sticks out to you when solar, QBO, PDO, AMO all align to give us another 09-10 or 95-96? Are you eyeing next year (Winter 17-18) since we may have a weak El Nino with a -QBO? 

To be honest though, most winters have been excellent lately without much Atlantic or Arctic blocking. Dobbs Ferry had 74" of snow in 13-14, which is only 16" less than our record snowfall of 90" from 1961 and even surpasses "good years" such as 93-94 and 02-03. I was in Putnam County for Feb 2015, and we had one night when it was -11F...there was ice across the Hudson River and even on the East River along the FDR Drive. NYC's snow pack reached 20" in early March 2015, and most of the suburban, wooded areas retained snow until at least March 20th, with shoveled piles left well into April. 

Last year was kind of disappointing, and this year may have some rough periods, but overall we've been seeing above average snowfall and some of our colder months relative to average during the Nov-Mar period. 

[tamarack]

21 hours ago, weathafella said:

Through 12/17:

BOS:  -2.8F

ORH: -3.0F

BDL: -1.8F

PVD: -2.5F

 

 

Thru 12/18: 

PWM:    -3.2

CAR:     -6.2

I'm at -6.1 thru the 18th (was at +7.7 same time last year), and today/tomorrow look to be 10-12F BN.  I'd need about +12 for 21-31 to reach avg temp.  I'd guess a finish closer to -4 is reasonable, and could make 2016 the 2nd coldest of 19 Decembers here.  (2013 with -6.3 is probably out of play, though the cold has overperformed thus far.)

[SnowGoose69]

1 hour ago, nzucker said:

It's ridiculously early to say this, but I think our best winter might be 2020-21, which is when the solar cycle should bottom out. That solar minimum may induce stronger blocking patterns, resulting in a -NAO/-AO. Global temperatures should also be colder than this year, as we are just starting to lose the heat generated by the 2015 Super El Niño. We will also be into a -AMO at that point. 

The bottom of last solar cycle was in 2008. New England/Upstate NY had a great winter in 2008-2009, with Big Black River, Maine setting a record low at -50F in Jan 2009. We all know 09-10 was an historic winter for the mid-Atlantic/NYC with four huge snowstorms: 12/19, 2/5, 2/10, 2/26. December 2010 also began with record NAO blocking before yielding to the low blocking pattern we've seen prevail since then. The shift essentially occurred as the solar cycle began its upswing in 2011, and since then we have not had sustained NAO blocking. Any high heights over Greenland have been transient, and it was entirely the favorable Pacific that propelled us to excellent winters in 13-14 (58" of snow in Bay Ridge, Brooklyn) and 14-15 (coldest Feb since 1934).

Coincidences? I think not. 

This is such a putrid solar max though compared to most in the recent past.  I've said before that it's possible the atmosphere responds to all mins and maxes in a similar way regardless of how weak they are relative to normal 

[40/70 Benchmark]

1 hour ago, nzucker said:

It's ridiculously early to say this, but I think our best winter might be 2020-21, which is when the solar cycle should bottom out. That solar minimum may induce stronger blocking patterns, resulting in a -NAO/-AO. Global temperatures should also be colder than this year, as we are just starting to lose the heat generated by the 2015 Super El Niño. We will also be into a -AMO at that point. 

The bottom of last solar cycle was in 2008. New England/Upstate NY had a great winter in 2008-2009, with Big Black River, Maine setting a record low at -50F in Jan 2009. We all know 09-10 was an historic winter for the mid-Atlantic/NYC with four huge snowstorms: 12/19, 2/5, 2/10, 2/26. December 2010 also began with record NAO blocking before yielding to the low blocking pattern we've seen prevail since then. The shift essentially occurred as the solar cycle began its upswing in 2011, and since then we have not had sustained NAO blocking. Any high heights over Greenland have been transient, and it was entirely the favorable Pacific that propelled us to excellent winters in 13-14 (58" of snow in Bay Ridge, Brooklyn) and 14-15 (coldest Feb since 1934).

Coincidences? I think not. 

Hopefully that will make turning 40 more palatable.

[JC-CT]

Hopefully that will make turning 40 more palatable.

Old man winter in training