December 2019

[doncat]

34°/19° temp split yesterday.... 21° low this am.

[the_other_guy]

18F at 8am. one last very cold morning before warm up

 

[bluewave]

Pretty big model disagreement now showing up to start January. The EPS has a milder MJO than the GEFS. So the EPS has a fast Pacific jet allowing the cold to stay bottled up near Alaska. The GEFS is colder. Small changes in the location of the forcing in the WP can make a significant difference. 

 

 

 

[the_other_guy]

Proclaiming the gospel on MJO phases 10 days from now is risky as best as we have seen over the past few winters

 

Much to the chagrin of many posters, We are entering into a milder period this week... That really is the only certainty because any changes are more than 10 days out at this point

[bluewave]

5 hours ago, jfklganyc said:

Proclaiming the gospel on MJO phases 10 days from now is risky as best as we have seen over the past few winters

 

Much to the chagrin of many posters, We are entering into a milder period this week... That really is the only certainty because any changes are more than 10 days out at this point

Who is proclaiming any day 10 MJO gospel? If you actually read my post, then  you see there is a small difference in the tropical forcing between the two models. That may be one of the reasons for the varying solutions. Even low frequency forcing changes can make  a big difference in our sensible weather. There is zero risk in pointing this out. 
 

 

 

 

[MJO812]

Cfs is still really cold for January.  The consensus right now is that January will be cold and potentially active. 

[bluewave]

19 minutes ago, Snow88 said:

Cfs is still really cold for January.  The consensus right now is that January will be cold and potentially active. 

Have to wait for the CFS best forecast range near the last few days of the month. It doesn’t have much skill before that. Notice the variation in the December forecasts during late November.

 

[donsutherland1]

Dreams of a white Christmas for the Middle Atlantic and southern New England regions will have to wait for at least another year. Milder air is now pushing into the region and will likely predominate through the much or all of the remaining days of December.

Through December 21, snowfall amounts for select cities include:

Allentown: 2.1" (1.6" below normal)
Atlantic City: 0.5" (2.1" below normal)
Boston: 11.5" (4.9" above normal)
Bridgeport: 5.5" (1.9" above normal)
Harrisburg: 0.2" (3.5" below normal)
Hartford: 21.1" (14.8" above normal)
Islip: 4.3" (1.7" above normal)
New York City: 2.5" (0.5" below normal)
Newark: 4.2" (0.7" above normal)
Philadelphia: 0.1" (2.1" below normal)
Providence: 8.0" (1.0" above normal)
Worcester: 25.3" (13.5" above normal)

Despite the warmth, which could take monthly departures toward and perhaps even above normal across many parts of the region, dreams of a snowy January persist. Perhaps a key to whether those dreams are realized will be the state of the Arctic Oscillation (AO) and Pacific North America (PNA) pattern.

Since 1950, 52 snowstorms brought 6" or more snow to at least one of the following cities: Boston, New York City, or Philadelphia. 60% of those storms had an AO-, 64% had a PNA+, and 38% had an AO-/PNA+. From among the 18 storms that brought 6" or more snow to at least two of those cities, 83% occurred with an AO-, 83% occurred with a PNA+, and 67% had an AO-/PNA+. From among the 11 storms that brought 6" or more snow to all three of those cities, 91% occurred with an AO-, 91% occurred with a PNA+, and 82% had an AO-/PNA+.

[White Gorilla]

33 minutes ago, Snow88 said:

Cfs is still really cold for January.  The consensus right now is that January will be cold and potentially active. 

Hopefully not cold and dry.  

[Cfa]

Hoping for the milder outcome, as always. Cold is useless, and even the mildest winters have snow, though a snowless winter in our climate is probably a case of when and not if.

[bluewave]

The Pacific Jet continues to make headlines.

 

[frd]

1 hour ago, bluewave said:

Who is proclaiming any day 10 MJO gospel? If you actually read my post, then  you see there is a difference in the the tropical forcing between the two models. That’s one of the reasons for the varying solutions. Even low frequency forcing changes can make  a big difference in our sensible weather. There is zero risk in pointing this out. 

Maybe forcing will shift as the + IOD weakens and takes on more favorable phase(s)  for cold as we go through January and enter February. So much more than the phase of the MJO, as you are aware and pointed out. Volatility reigns in the model world. There have been some prior significant changes in the EPS this fall. But, no idea how this will turn out.  

[IrishRob17]

Finally got above freezing for the first time since last Monday, looking forward to the driveway becoming less treacherous over the next couple of days. 
 

[HeadInTheClouds]

6 minutes ago, IrishRob17 said:

Finally got above freezing for the first time since last Monday, looking forward to the driveway becoming less treacherous over the next couple of days. 
 

Me too. 36 here. Feels like a heatwave. 

[uncle W]

the ao forecast continues to be very positive around new years...a bad sign if you want major snow and cold...

[bluewave]

17 minutes ago, frd said:

Maybe forcing will shift as the + IOD weakens and takes on more favorable phase(s)  for cold as we go through January and enter February. So much more than the phase of the MJO, as you are aware and pointed out. Volatility reigns in the model world. There have been some prior significant changes in the EPS this fall. But, no idea how this will turn out.  

Sometimes the long range can be more difficult to figure out with multiple areas of weak forcing. Almost impossible to guess which area will tip the scales in one direction or the other. That forcing and Pacific Jet can make the difference in the location and strength of the NEPAC ridge. 

[donsutherland1]

13 minutes ago, NYCweatherNOW said:

All those forecasts are bull!

weather is unpredictable and so are those indexes 

Even 10-day forecasts have skill (coefficient of correlation around 0.7):

Beyond 10-days such forecasts are not skillful (coefficient of correlation < 0.5)

[binbisso]

47 minutes ago, IrishRob17 said:

Finally got above freezing for the first time since last Monday, looking forward to the driveway becoming less treacherous over the next couple of days. 
 

Yea so much for the one day in and out cold snap. We mild up for a week then who knows after that. Too many conflicting signals in the longer range

[uncle W]

when you see most of the members very high its on to something...the Pacific better help out if its right...

[IrishRob17]

48 minutes ago, HeadInTheClouds said:

Me too. 36 here. Feels like a heatwave. 

 

7 minutes ago, binbisso said:

Yea so much for the one day in and out cold snap. We mild up for a week then who knows after that. Too many conflicting signals in the longer range

Yep. It sure is a beauty out there now but it will take a lot more to get the driveway clear.  Here’s a shot of part of it, north facing and stone FTL this time of year. 

[binbisso]

48 minutes ago, uncle W said:

the ao forecast continues to be very positive around new years...a bad sign if you want major snow and cold...

The ao was very pos the first half of december and we were slightly below normal thru the 15th. If the tpv takes up shop over northern canada/hudson bay in early jan. as some guidance suggests then it will be plenty cold with a pos ao. 

[binbisso]

11 minutes ago, IrishRob17 said:

 

Yep. It sure is a beauty out there now but it will take a lot more to get the driveway clear.  Here’s a shot of part of it, north facing and stone FTL this time of year. 

Nice. its been a wintry first 22 days of december for many in this sub forum and all of new england. When you look at bluewaves map of the whole country most lr forecasters actually got the longwave pattern right except for the Northeast. Wonder if they didnt take into account the 50/50 area which has had consistently lower heights this month and probably contributed to the - departures

[bluewave]

1 hour ago, binbisso said:

Nice. its been a wintry first 22 days of december for many in this sub forum and all of new england. When you look at bluewaves map of the whole country most lr forecasters actually got the longwave pattern right except for the Northeast. Wonder if they didnt take into account the 50/50 area which has had consistently lower heights this month and probably contributed to the - departures

That’s why it can be difficult making monthly or seasonal forecasts in weak ENSO regimes. December cold in New England is typically something we see during La Ninas.

December to date

Recent La Niña composite cold in New England

 

 

[NEG NAO]

2 hours ago, uncle W said:

the ao forecast continues to be very positive around new years...a bad sign if you want major snow and cold...

[Cfa]

2 hours ago, IrishRob17 said:

 

Yep. It sure is a beauty out there now but it will take a lot more to get the driveway clear.  Here’s a shot of part of it, north facing and stone FTL this time of year. 

Looks like another world compared to here.

[MJO812]

29 minutes ago, NEG NAO said:

People have told me to take these with a grain of salt because its based off the gfs.

[Cfa]

Managed to reach 50 today, full sunshine made it feel even warmer, B+ rating for the first full day of winter.

[NEG NAO]

17 minutes ago, Snow88 said:

People have told me to take these with a grain of salt because its based off the gfs.

what people ?

 

[CPcantmeasuresnow]

55 minutes ago, Cfa said:

Managed to reach 50 today, full sunshine made it feel even warmer, B+ rating for the first full day of winter.

Topped out at 45 here. I’ll go with a solid D. 

[NEG NAO]