December Forecast Discussion

[REDMK6GLI]

Only a week away from december and the start of meteorlogical winter. Lets discuss here the month of december, many signs pointing to a backended winter and hints that the pattern may start to lock in towards the end of the month. -NAO is yet to set up shop and has been one of the teleconnectors lacking thus far.

[SnoSki14]

Probably not much to talk about for the first 10 days at least of December to perhaps longer if you're looking for winter weather.

The biggest things to look for in a mild pattern is how that pattern will or can progress beyond that. As far as I know many of the METS are convinced we turn the corner post 15th so we shall see.

[REDMK6GLI]

Probably not much to talk about for the first 10 days at least of December to perhaps longer if you're looking for winter weather.

The biggest things to look for in a mild pattern is how that pattern will or can progress beyond that. As far as I know many of the METS are convinced we turn the corner post 15th so we shall see.

Agreed first half of december will be quite tame with normal to slightly above normal temp anomolies. Mid month is when we should start seeing changes that will increase our snow chances again

[CIK62]

The CFS weeklies all show above normal heights in the northeast through December 26.    Of course they showed this for November too but were wrong.    So the question is what is happening in the atmosphere, stratosphere and the Pacific/Atlantic that the weekly analogs are not picking up on and why aren't they doing so.   Seems the cold stays near Hudson Bay all month.

[PB GFI]

The Euro control shows how Canada will be seeded as we warm over the CONUS from about the 1st thru the 10th .

But this is what is waiting to swing back through around the 11th or 12ths time frame .

 

Look at the ensembles at day 15 . That ridge off the WC starts to set back up and the correction east of the rockies should mean a deeper trough into the east . That cold air should slide back in for a mid month chill down . 

[CIK62]

Probably not much to talk about for the first 10 days at least of December to perhaps longer if you're looking for winter weather.

The biggest things to look for in a mild pattern is how that pattern will or can progress beyond that. As far as I know many of the METS are convinced we turn the corner post 15th so we shall see.

The 'perhaps longer' is probably right.   Those hoping for a better week 2 in December ought to know the CFS weeklies go off their regular scale on the high end at that time.   In fact as of today no below normal 2mT are indicated anywhere in the USA for the duration of this analog's range which is through next summer!   Only some near normal periods.    I have screen captured these maps for what it is worth and will monitor for real non-imagined changes that I can compare them with.

[KEITH L.I]

The 'perhaps longer' is probably right.   Those hoping for a better week 2 in December ought to know the CFS weeklies go off their regular scale on the high end at that time.   In fact as of today no below normal 2mT are indicated anywhere in the USA for the duration of this analog's range which is through next summer!   Only some near normal periods.    I have screen captured these maps for what it is worth and will monitor for real non-imagined changes that I can compare them with.

CFS had a blowtorch nationwide for November..that should tell you something about the CFS..it has very little skill,and pass two weeks most LR forecasting is like flipping a coin..MJO is basically controlling the next few weeks..afterwards we will go into a more favorable phase 

[REDMK6GLI]

CFS had a blowtorch nationwide for November..that should tell you something about the CFS..it has very little skill,and pass two weeks most LR forecasting is like flipping a coin..MJO is basically controlling the next few weeks..afterwards we will go into a more favorable phase

Indeed the CFS failed miserably for november with its nationwide blowtorch, when in actuality we had cold comparable to 76-77

[Eduardo]

The strong MJO pulse going into 3-4-5 is what shifted the forecasts milder during the

first week of December. Otherwise, the strong +PDO signature with an El Nino

would have kept the the PNA positive instead of dipping negative to neutral.

 

ECMF_phase_51m_full.gif

 

combined_image.png

 

Awesome post from bluewave, as usual.  I think that's right on the money.  Seems like once the MJO either moves towards Phase 7 or dwindles down, the indices about which we've been excited since October can work their magic.  I definitely remain optimistic!

[uncle W]

December decade averages...extremes...
decade..ave.temp..high..low...ave.max/min..max..min...precipitation...snowfall
1870's......32.7......37.4......24.9...........................64......-2...2.88"...6.7"
1880's......33.6......40.0......26.5......57.3.....7.9....67......-6...3.28"...7.1"
1890's......35.9......42.3......29.9......58.8...12.0....66.......8...2.97"...4.3"
1900's......34.8......38.9......30.3......57.1...13.6....64.......4...3.95"...6.2"
1910's......34.1......39.4......25.0......59.4...10.8....64....-13...3.80"...7.5"
1920's......35.5......42.0......28.9......59.0...13.2....68.......7...3.49"...4.2"
1930's......35.9......41.0......30.0......61.2...11.7....68......-6...2.86"...4.3"
1940's......35.4......39.4......31.0......59.5...11.7....70......-4...3.39"...9.1"
1950's......36.8......41.3......29.4......59.7...12.0....67.......5...3.49"...4.7"
1960's......34.8......40.5......30.9......61.6...12.9....68.......4...3.70"...7.4"
1970's......37.4......41.1......29.9......61.6...17.6....67.......9...4.63"...1.7"
1980's......36.6......43.8......25.9......61.0...11.8....72......-1...3.14"...2.1"
1990's......39.5......43.2......32.4......64.0...16.5....75.....10...4.04"...2.9"
2000's......37.7......44.1......31.1......62.9...16.6....71.....11...4.45"...7.8"
2010's......39.2......43.3......32.8......62.8...22.0....71.....19...4.48"...7.3"
1870-
2009.........35.6.................................60.2...12.9....................3.58"...5.4"
1980-

2009.........37.9.................................62.6...15.0....................3.88"...4.3"

Coldest............warmest............wettest..........Driest......
24.9 in 1876 ... 44.1 in 2001 ... 9.98" in 1973 ... 0.25" in 1955
25.0 in 1917 ... 43.8 in 1984 ... 9.77" in 1983 ... 0.58" in 1980
25.9 in 1989 ... 43.6 in 2006 ... 7.53" in 1936 ... 0.68" in 1877
26.5 in 1880 ... 43.3 in 2011 ... 7.27" in 2009 ... 0.83" in 1989
26.7 in 1872 ... 43.2 in 1998 ... 7.07" in 1969 ... 0.83" in 1985
28.9 in 1926 ... 42.8 in 1982 ... 7.01" in 1901 ... 0.98" in 1928
29.2 in 1871 ... 42.6 in 1990 ... 6.77" in 1902 ... 1.12" in 1998
29.4 in 1958 ... 42.3 in 1891 ... 6.62" in 2008 ... 1.13" in 1988
29.6 in 1886 ... 42.2 in 1994 ... 6.48" in 1996 ... 1.13" in 1896
29.7 in 1955 ... 42.0 in 1923 ... 6.33" in 1974 ... 1.20" in 1943
Warmest temperatures...
75 1998 12/7
74 1998 12/4
72 1982 12/4

71 2013 12/22
71 2001 12/6
70 1946 12/10
70 2006 12/1
70 2001 12/5
70 1984 12/29
Coldest temperatures...
-13 1917 12/30
-7 1917 12/31
-6 1917 12/29
-6 1880 12/30
-6 1933 12/30
-4 1942 12/20
-3 1884 12/20
-3 1933 12/29
-3 1880 12/31
Coldest monthly max...
47 in 1917
49 in 1876
49 in 1880
49 in 1890
49 in 1926
Warmest monthly min...
28 in 2012
26 in 1974
25 in 1984
24 in 1908
23 in 1923
22 in 1907
22 in 1918
22 in 2011
Greatest monthly snow...
29.6" in 1947
27.0" in 1872
25.3" in 1948
22.5" in 1883
20.1" in 2010
19.8" in 2003
18.6" in 1960
15.8" in 1959
15.6" in 1945
14.9" in 1933
14.5" in 1916
Biggest snowfalls...
26.4" 1947 12/26-27
20.0" 2010 12/26-27
18.0" 1872 12/26
16.0" 1948 12/19-20
15.2" 1960 12/11-12
14.0" 2003 12/5-7
13.7" 1959 12/21-22
12.7" 1916 12/15
12.0" 2000 12/30
11.4" 1912 12/24
11.2" 1933 12/26
10.9" 2009 12/19-20

.....................................................................................

Greatest White Christmas's in NYC...
Snow cover on the ground Christmas morning ...
snowfalls that started after that don't count...1883 probably had the snowiest Christmas with over 6" on the ground and 5 more inches Christmas day...1912 had the most snow on the ground Christmas morning from an 11.4" snowfall on 12/24...11" was on the ground Christmas morning...1945 and 1966 had 7" snow depth...1961 and 1963 6"...
year...snow on ground...dates of storms...
since 1910....
1912.....11".........11.4" 12/24
1914.....trace........0.6" 12/24.....0.4" 12/21...
1917.......4"..........9.6" 12/12-14.....0.2" 12/17.....
1919.......3"..........2.8" 12/24-25.....1.9" 12/19.....2.1" 12/16-17
1924.....trace.......0.8" 12/24-25
1925.....trace.......0.2" 12/24-25
1929.......1"..........1.4" 12/23
1930.......2"..........3.9" 12/23-24...
1935.....trace.......0.4" 12/23.....0.4" 12/20.....1.6" 12/25-26
1945.......7"..........8.1" 12/19-20...3.2" 12/14...0.6" 12/10
1947.......1"..........2.5" 12/23
1948.......5"........16.0" 12/19-20
1955......trace.......2.7" 12/22
1959.......4"........13.7" 12/21-22
1960.......1"........15.2" 12/11-12.....1.3" 12/19
1961.......6"..........6.2" 12/23-24
1962......trace.......2.7" 12/21-22......0.3" 12/25...rain Christmas night...
1963.......6"..........6.6" 12/23-24......1.4" 12/18.....2.3" 12/12
1966.......7"..........7.1" 12/24-25......1.2" 12/21
1967......trace.......1.0" 12/23....rain Christmas night...
1970......trace.......2.1" 12/21-23
1975......trace.......1.8" 12/22...0.5" 12/25...Rain Christmas night...
1980......trace.......1.0" 12/24...0.6" 12/23
1983.......1"..........1.0" 12/23-24
1993......trace.......trace 12/24-25
1995.......4"..........7.7" 12/19-20...0.5" 12/16...1.7" 12/14...1.5" 12/9...
1998.......1"..........2.0" 12/23-24
2000......trace.......0.7" 12/20
2002......trace.......trace 12/25...5" 12/25 after morning rain...
2009.......2"........10.9" 12/19-20....rain Christmas night...

[SnoSki14]

I think this December will end up +2 for the city and most areas in the tristate in the +1.5-2 range.

I don't think we see the effects of a colder pattern until the last third of the month. Could be great timing for the holidays.

[Doorman]

GFS 850mb temp guidance thru Dec 6th 

 

 

http://climate.cod.edu/flanis/model/mod/index.php?type=06-GFS-WLD-850-temp-6-1

[CIK62]

12Z GFS showed two good setups for EC storms but all the way out @300hrs. & @348hrs.   Seemed to result from a favorable movement of the next typhoon in Pacific.

[FoggyO]

Polar Vortex is splitting and will be back in the USA by the middle of December thanks to the NAO turning negative and funneling the Vortex into the USA.

 

I suspect that this pattern will continue on and off throughout the Winter. 

[metwannabe]

Polar Vortex is splitting and will be back in the USA by the middle of December thanks to the NAO turning negative and funneling the Vortex into the USA.

I suspect that this pattern will continue on and off throughout the Winter.

The PV is not splitting currently

[WeatherFox]

PROGNOSTIC DISCUSSION FOR MONTHLY OUTLOOK

NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
830AM EST THURSDAY NOV 20 2014

30-DAY OUTLOOK DISCUSSION FOR DECEMBER 2014

THE OUTLOOK FOR DECEMBER 2014 IS DECIDEDLY UNCERTAIN AT THIS POINT...

 

At least they are honest 

[Weathergun]

The PV is not splitting currently

There is at least partial PV split occurring now at every level. However, the latest Euro/GFS forecasts the PV to recover somewhat over the north pole in the medium range. So we aren't likely to any sustained high-latitude blocking on our side of the hemisphere,for at least the first two weeks of December. Unless these forecasts change:

 

[MJO812]

Something to watch  for the middle of next week. Nice Cold air damming signature. Inland areas look to do well with this. Too warm for the coast as of now.

http://mag.ncep.noaa.gov/Image.php?fhr=096ℑ=data%2Fgfs%2F06%2Fgfs_namer_096_10m_wnd_precip.gif&model=gfs&area=namer&param=10m_wnd_precip&group=Model+Guidance&preselected_formatted_cycle_date=20141129+06+UTC&imageSize=M&ps=area

[PB GFI]

Something to watch  for the middle of next week. Nice Cold air damming signature. Inland areas look to do well with this. Too warm for the coast period

http://mag.ncep.noaa.gov/Image.php?fhr=096ℑ=data%2Fgfs%2F06%2Fgfs_namer_096_10m_wnd_precip.gif&model=gfs&area=namer&param=10m_wnd_precip&group=Model+Guidance&preselected_formatted_cycle_date=20141129+06+UTC&imageSize=M&ps=area

Fixed

[WeatherFox]

Something to watch  for the middle of next week. Nice Cold air damming signature. Inland areas look to do well with this. Too warm for the coast as of now.

http://mag.ncep.noaa.gov/Image.php?fhr=096ℑ=data%2Fgfs%2F06%2Fgfs_namer_096_10m_wnd_precip.gif&model=gfs&area=namer&param=10m_wnd_precip&group=Model+Guidance&preselected_formatted_cycle_date=20141129+06+UTC&imageSize=M&ps=area

Here we go again .  Something to pique our interest and to spend our time tracking & hoping - only to get disappointed again in the end.

[Doorman]

Day 4 WPC outlook

 

http://www.wpc.ncep.noaa.gov/medr/medr.shtml

 

 

Day 7 for good measure

 

 

the song remains the same

[easternsnowman]

Any frozen events over the next two weeks will probably be well north and west of the city.

[SnowGoose69]

Something to watch  for the middle of next week. Nice Cold air damming signature. Inland areas look to do well with this. Too warm for the coast as of now.

http://mag.ncep.noaa.gov/Image.php?fhr=096ℑ=data%2Fgfs%2F06%2Fgfs_namer_096_10m_wnd_precip.gif&model=gfs&area=namer&param=10m_wnd_precip&group=Model+Guidance&preselected_formatted_cycle_date=20141129+06+UTC&imageSize=M&ps=area

 

The Euro has an overrunning event around 168 hours...if the wave remains weak thats a classic setup for a few inches of snow.

[PB GFI]

Once to mid month and we should be  back in business .

[WeatherFox]

Once to mid month and we should be  back in business .

That being the case the following forecasters are likely out of the one inch contest.  Of course time will tell, as old man winter can pull off a surprise.

 

Chaser25973 Nov 29

Uncle W Nov 29

TonyLovesSnow Nov 30

Cik62 Nov 30

Uscgrs Dec 1

CFA Dec 2

Frankdp23 Dec 3

Snowlover11 Dec 3

Snowski 14 Dec 4

IntenseBlizzard2014 Dec 5

Jc-ct Dec 5

Alexa Dec 5

Imperator Dec 5

Plfdwxdude Dec 6

Rjay Dec 7

Mullen Dec 7

[REDMK6GLI]

Once to mid month and we should be  back in business .

if we don't see any signs of blocking or any sensible pattern change towards snow or cold we are gonna start seeing high amounts of punting as we head towards mid December

[PB GFI]

Euro MJO

[Doorman]

Once to mid month and we should be  back in business .

but I digress   

 

http://www.esrl.noaa.gov/psd/map/images/ens/t850std_f360_us.html

 

 

polar to equator incongruity

[PB GFI]

but I digress   

 

http://www.esrl.noaa.gov/psd/map/images/ens/t850std_f360_us.html

 

850-max.gif

Also the Euro bias MJO agrees with the UKMET and NCEP MJO showing more amplitude through 7 8  .

The trough should find its way east by then .

[Dsnowx53]

I mean we'll almost definitely have some sort of +PNA in the 2nd week of December, but the airmass as of now looks pretty stale and the Atlantic pattern is pretty bad.