Jump to content
  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

December 2016 Discussion & Observations


bluewave

Recommended Posts

32 minutes ago, donsutherland1 said:

Today, the Arctic Oscillation (AO) rocketed to +3.879. That brings the December average to +0.953.

Typically, such a positive AO suggests a mild first half of January. Since 1950, there have been nine years during which the AO peaked at +3.500 or above in the December 20-31 period. Only two of those cases featured a colder-than-normal January 1-15. This does not necessarily mean that "winter is over." In two thirds of the cases, combined January-February-March snowfall came to 15" or more in New York City (Mean: 17.8"; Median: 16.4"). In one-third of the cases, it exceeded 20". Only a single case saw less than 10" snowfall during that timeframe.

More details are below:

 

Don, it's noteworthy how different the pattern was over the Arctic and Eurasia this October and November compared to the other years with 

the December near record +AO readings.

 

16.png

 

comp.png

 

 

 

 

Link to comment
Share on other sites

  • Replies 1.4k
  • Created
  • Last Reply
6 minutes ago, bluewave said:

 

It's noteworthy how different the pattern was over the Arctic and Eurasia this October and November compared to the other years with 

the December near record +AO readings.

 

16.png

 

comp.png

 

 

 

 

I agree. Perhaps the Arctic sea ice is one variable that contributed to the outcome this year.

Link to comment
Share on other sites

42 minutes ago, bluewave said:

I think that NYC will only need to go about (+4) 12/21 to 12/31 to break even. Most other stations are warmer so they will need less.

December temperature departures through the 19th.

NYC...-1.7

LGA...-0.4

JFK...-0.2

ISP...-0.9

BDR..+0.3

EWR...-1.1

 

 

NYC is -2.2 after today.

The last 11 days will need to average +6.5 to end up average.

Link to comment
Share on other sites

2 minutes ago, TheJMan said:

Still very new here, well posting wise, have been peeping this forum for a little over a year now (aspiring meteorologist), but does 12z Dec 24th (looking at the GFS) bring any hope to us (I am CNJ ish)? 

Doubtful take it for it is, we'll have plenty of chances for snow this winter just not on Christmas Eve.

Link to comment
Share on other sites

 

Just now, WeatherFeen2000 said:

Doubtful take it for it is, we'll have plenty of chances for snow this winter just not on Christmas Eve.

Yeah, family will be up here from Texas for a week at the end of dec, was hoping to show them some real snow lol, optimism will continue though 

Link to comment
Share on other sites

8 minutes ago, TheJMan said:

Still very new here, well posting wise, have been peeping this forum for a little over a year now (aspiring meteorologist), but does 12z Dec 24th (looking at the GFS) bring any hope to us (I am CNJ ish)? 

Welcome

I think areas to the north of NYC have a chance of some snow.

Link to comment
Share on other sites

1 minute ago, Snow88 said:

Welcome

I think areas to the north of NYC have a chance of some snow.

Thats cool, still self learning how this tracking goes, and after looking at everybodies posts from over time, and finding tropical tidbits I am still disecting the ins and out of prediction.  I saw the potential there, but being so far away, and the time gap from 12z to 18z i figured something would develop. 

Link to comment
Share on other sites

30 minutes ago, WeatherFeen2000 said:

It sure looked decent

Models have been gradually backing off the extent of the warm pattern. Initially, the ridge to our north is so strong it creates a confluent high pressure in Quebec. That limits the northward progression of the warmth Dec 25-26. Add to that the clipper on 12/22, which makes for a cold Thursday night and Friday. Models are trending towards a deeper trough which means 20s Friday AM.

In the longer range, the GFS is faster in bringing the trough back to the East. We know the PV is going to stay in North America, so any troughing could bring extreme cold as the 18z run shows in the clown range. Most forecasters think the trough is back by 1/10, but the question is whether it is sooner than that.

It will be hard to finish December above normal with the cold Friday and muted warm-up. The cutter ends up so far west that it includes and the warmth is pinched off before the Arctic high in SE Canada can depart.

 

Link to comment
Share on other sites

1 hour ago, pazzo83 said:

Dude look at that blob of crazy + anomalies over Hudson Bay - bye bye sea ice.

Nah, that's actually heat released from the ice freezing. Notice how much warmer 2m temperatures are over the part of the Bay that hasn't finished freezing yet, compared to both the land nearby in Quebec/Ontario and the already frozen northwest part of Hudson Bay. 

850s are like -20C to -25C over Hudson Bay the next week. That's why it's freezing, causing tremendous amounts of heat to be released.

Link to comment
Share on other sites

3 hours ago, nzucker said:

Models have been gradually backing off the extent of the warm pattern. Initially, the ridge to our north is so strong it creates a confluent high pressure in Quebec. That limits the northward progression of the warmth Dec 25-26. Add to that the clipper on 12/22, which makes for a cold Thursday night and Friday. Models are trending towards a deeper trough which means 20s Friday AM.

In the longer range, the GFS is faster in bringing the trough back to the East. We know the PV is going to stay in North America, so any troughing could bring extreme cold as the 18z run shows in the clown range. Most forecasters think the trough is back by 1/10, but the question is whether it is sooner than that.

It will be hard to finish December above normal with the cold Friday and muted warm-up. The cutter ends up so far west that it includes and the warmth is pinched off before the Arctic high in SE Canada can depart.

 

I don't know if I'd call Friday cold. We're expecting highs in the mid 40s, which is slightly above normal. 

Link to comment
Share on other sites

using smoothed numbers is like using apples and oranges...The 1981-2010 December average temperature is 37.9...NOAA has 37.5...-0.4 lower than the actual number...NYC is averaging 37.0 as of yesterday...That could rise a bit this week.....if it does torch next week then it could go above 38.0...

Link to comment
Share on other sites

Today's preliminary Arctic Oscillation (AO) figure is +4.660. That broke the daily record of +3.837 from last year. Last December saw the AO peak on 12/22 at +4.503. Overall, this is the highest AO figure since March 9, 2015 when the Arctic Oscillation reached +4.952. For purposes of comparison, the record low figure for this date was -5.821 in 2009.

Link to comment
Share on other sites

44 minutes ago, donsutherland1 said:

Today's preliminary Arctic Oscillation (AO) figure is +4.660. That broke the daily record of +3.837 from last year. Last December saw the AO peak on 12/22 at +4.503. Overall, this is the highest AO figure since March 9, 2015 when the Arctic Oscillation reached +4.952. For purposes of comparison, the record low figure for this date was -5.821 in 2009.

Don, which site do you use to get the preliminary numerical daily updates on the AO? I see the bar graph updating in real time but not numerical output.

This site updates after the month is over.

http://ftp.cpc.ncep.noaa.gov/cwlinks/norm.daily.ao.index.b500101.current.ascii

Link to comment
Share on other sites

16 minutes ago, bluewave said:

Don, which site do you use to get the preliminary numerical daily updates on the AO? I see the bar graph updating in real time but not numerical output.

This site updates after the month is over.

http://ftp.cpc.ncep.noaa.gov/cwlinks/norm.daily.ao.index.b500101.current.ascii

Bluewave,

They're posted here: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/daily.index.ascii

 

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...