December 2017 Discussions & Observations Thread

[Stormlover74]

Just now, Paragon said:

February and December were the worst, two awful forecast busts lol.  Watching ACY get 20" while we got virga wasn't pretty either.

I was in school at the time waiting for the snow to start, each hour that went by I got more depressed. Then with the Dec 15 storm snow started on schedule and 5 minutes later it was raining. Had no weather channel or radar or anything to figure out what was going on, only that is was pouring rain instead of dumping snow

[Paragon]

Just now, Stormlover74 said:

I was in school at the time waiting for the snow to start, each hour that went by I got more depressed. Then with the Dec 15 storm snow started on schedule and 5 minutes later it was raining. Had no weather channel or radar or anything to figure out what was going on, only that is was pouring rain instead of dumping snow

haha I actually decided to play hooky to watch the snow fall and spent all day looking out the window seeing nothing but overcast skies.

I actually ended up writing a short story called The Last Snow that day about kids waiting for the last snowstorm to occur before climate change made snowstorms extinct lol- and as a last FU that Last Snowstorm ended up being a bust....

That was 2/89

With 12/89 I was listening to Craig Allen on WCBS trying to find out why we had a clap of thunder and then it changed to rain  He said something about the secondary forming too close to the coast.  I got so angry I threw the radio against the wall (didn't break it.)

 

[MJO812]

Euro at 240 has a big Miller A

[Stormlover74]

3 minutes ago, Paragon said:

haha I actually decided to play hooky to watch the snow fall and spent all day looking out the window seeing nothing but overcast skies.

I actually ended up writing a short story called The Last Snow that day about kids waiting for the last snowstorm to occur before climate change made snowstorms extinct lol- and as a last FU that Last Snowstorm ended up being a bust....

That was 2/89

With 12/89 I was listening to Craig Allen on WCBS trying to find out why we had a clap of thunder and then it changed to rain  He said something about the secondary forming too close to the coast.  I got so angry I threw the radio against the wall (didn't break it.)

 

Ha, I can imagine. 

The worst part was then it turned bitterly cold and we flipped to snow but then it ended and we were left with cold and dry for the next 2 weeks, though we did get snow showers that would occasionally whiten the ground almost every day from the 19th to the 24th. Then our next storm hit around the 30th and temps were around freezing but we ended up with a sloppy mix of rain/freezing drizzle before we flipped to warm and boring the rest of the winter.

[Paragon]

1 minute ago, Stormlover74 said:

Ha, I can imagine. 

The worst part was then it turned bitterly cold and we flipped to snow but then it ended and we were left with cold and dry for the next 2 weeks, though we did get snow showers that would occasionally whiten the ground almost every day from the 19th to the 24th. Then our next storm hit around the 30th and temps were around freezing but we ended up with a sloppy mix of rain/freezing drizzle before we flipped to warm and boring the rest of the winter.

Yeah the only other things I remember about that winter was a slop storm around New Years Eve and then a steam bath the rest of the season and then everyone wearing shorts in the middle of March when it was in the mid-upper 80s for days.  Somehow we had a small snow "event" in early April and then it went right back to warm.

 

[Stormlover74]

1 minute ago, Paragon said:

Yeah the only other things I remember about that winter was a slop storm around New Years Eve and then a steam bath the rest of the season and then everyone wearing shorts in the middle of March when it was in the mid-upper 80s for days.  Somehow we had a small snow "event" in early April and then it went right back to warm.

 

A week before the heat wave there was a clipper that stalled and gave us around 3-4" which was our 2nd biggest of the season. I also remember a clipper in late Feb. The following winter we got lucky with the late Dec storm and the Jan snow to rain event. It was a very mild winter but we lucked out with timing to sneak out 2 decent events.

[Paragon]

15 minutes ago, Stormlover74 said:

A week before the heat wave there was a clipper that stalled and gave us around 3-4" which was our 2nd biggest of the season. I also remember a clipper in late Feb. The following winter we got lucky with the late Dec storm and the Jan snow to rain event. It was a very mild winter but we lucked out with timing to sneak out 2 decent events.

Oh yes, we were right in the middle of a "no 6" inch event streak that lasted for a few years (we saw another streak like that in the late 90s but that seemed different because we'd already had big winters in 93-94 and 95-96.)  1991 was our hottest year on record at the time (breaking the record from the previous year), and we had a record 90 degree summer that year and Hurricane Bob at the tail end of it.  I think that's where my fascination with heat came from- there was nothing else exciting about our weather at that time.  1993-94 and 1995-96 were my favorite seasons until the 09-12 period because we had the best combination of heat, cold and snow/ice.

 

 

[bluewave]

Models continue to trend stronger on the NE PAC block. 

 

 

 

[SnowGoose69]

52 minutes ago, Stormlover74 said:

A week before the heat wave there was a clipper that stalled and gave us around 3-4" which was our 2nd biggest of the season. I also remember a clipper in late Feb. The following winter we got lucky with the late Dec storm and the Jan snow to rain event. It was a very mild winter but we lucked out with timing to sneak out 2 decent events.

The 90-91 winter had a massive east based NAO.  It was so east based it didn't even qualify officially as a negative NAO but Europe got destroyed that winter and occasionally the eastern US benefited 

[danstorm]

25 minutes ago, bluewave said:

Models continue to trend stronger on the NE PAC block. 

 

 

 

That 500 mb pattern is NOT one that screams boring.

[SnoSki14]

1 hour ago, bluewave said:

Models continue to trend stronger on the NE PAC block. 

 

 

 

I expect a KU will eventually unfold out of this pattern, we've been able to get significant snow events with a far less ideal pattern than what's presented. 

There were already signs of that with the Day 10 Euro OP.

[forkyfork]

1 hour ago, bluewave said:

Models continue to trend stronger on the NE PAC block. 

 

 

 

also more poleward with the blocking with a deeper -ao

[Paragon]

21 minutes ago, bluewave said:

That day 11-15 more poleward extension of the block is looking like a combination of January 1994, 2004, and 2014.

 

 

That's a highly extreme combo you have there.....the first two are among the coldest (and stormiest) months on record for us.  It might have some impact on sustainability, as patterns that extreme don't usually just go away after a couple of weeks.

 

 

[UlsterCountySnowZ]

Prolonged cold into mid dcember looking more and more likely, trough positioning through entire EPS run doesn’t change much once we cold 

[MJO812]

EPO on the GFS reaches -7 deviation by mid December

[RedSky]

4 hours ago, Paragon said:

haha I actually decided to play hooky to watch the snow fall and spent all day looking out the window seeing nothing but overcast skies.

I actually ended up writing a short story called The Last Snow that day about kids waiting for the last snowstorm to occur before climate change made snowstorms extinct lol- and as a last FU that Last Snowstorm ended up being a bust....

That was 2/89

With 12/89 I was listening to Craig Allen on WCBS trying to find out why we had a clap of thunder and then it changed to rain  He said something about the secondary forming too close to the coast.  I got so angry I threw the radio against the wall (didn't break it.)

 

Somehow someway my NOAA weather cube survived the 80's in operational condition and I still have it. The engineer that designed it went on to great success another of his accomplishments was that blue shed in Texas.

 

[Rtd208]

Earthlight

 

[Rtd208]

 

[IntenseBlizzard2014]

1 hour ago, Rtd208 said:

 

That's gonna kick up the heights over Western Canada. If that's timed properly with the vort over the SW US. That will make way for a rather strong Miller A through December 10th. The question is: will the NAO block begin to fade by then?

[uncle W]

the December 24-25th, 1966 snowstorm along the east coast had a positive nao...it had a negative ao and positive pna...

[IntenseBlizzard2014]

43 minutes ago, uncle W said:

the December 24-25th, 1966 snowstorm along the east coast had a positive nao...it had a negative ao and positive pna...

That sounds very interesting. I wonder how the H5 looked like for that storm.

[uncle W]

13 minutes ago, IntenseBlizzard2014 said:

That sounds very interesting. I wonder how the H5 looked like for that storm.

 

[Juliancolton]

16 minutes ago, IntenseBlizzard2014 said:

That sounds very interesting. I wonder how the H5 looked like for that storm.

12z 12/25/66:

ftp://ftp.library.noaa.gov/swm.docs.lib/1966/19661225.pdf

[IntenseBlizzard2014]

28 minutes ago, uncle W said:

 

 

29 minutes ago, Juliancolton said:

12z 12/25/66:

ftp://ftp.library.noaa.gov/swm.docs.lib/1966/19661225.pdf

Thanks guys. We pulled off a significant snowstorm with a decent upper flow like this. I'm pretty happy to see that the upcoming pattern will be more supportive of a potential significant snowstorm at some point this month. 

[Paragon]

3 hours ago, uncle W said:

the December 24-25th, 1966 snowstorm along the east coast had a positive nao...it had a negative ao and positive pna...

One of my favorite seasons that I have read about   A rare Christmas eve snowstorm too  followed by a truly epic February and March tandem in 1967.  Came after a historically hot summer too.

 

 

[bluewave]

 Cold  -EPO/+PNA/-AO/neutral NAO pattern arriving after December 6th. Main NH blocking regions are forecast to be from The NE Pacific to the Kara.

 

 

 

[donsutherland1]

Since confidence in the development of large-scale, long-duration blocking is high, below is a chart depicting the distribution of New York City's 4" or greater snowstorms in December (1950-2016) based on the state of the AO and PNA.

Since 1950, there have been 24 such snowstorms. 6 or 25% brought 10" or more snow. The AO-/PNA+ dual blocking accounted for 50% of those storms. Even as the AO was more important that the state of the PNA when it came to the frequency of 4" or more snowstorms, the PNA was the principal factor when it came to 10" or greater snowstorms, with the PNA+ being present for 83% of such storms.

[Ralph Wiggum]

Very cold  -EPO/+PNA/-AO/neutral NAO pattern arriving after December 6th. Main NH blocking regions are forecast to be from The NE Pacific to the Kara.

 

 

 

 

 

 

 

 

 

I like it.....inverted Omega look on that map. Question......does that ridge qualify as being in the NAO region? Or is it too far displaced S and E being more of a WAR? With that said, what are the implications of the NAO/WAR feature being located in that region irt potential storm tracks verbatim?

 

 

Eta: 'inverted'

[bluewave]

24 minutes ago, Ralph Wiggum said:

58 minutes ago, bluewave said:

Very cold  -EPO/+PNA/-AO/neutral NAO pattern arriving after December 6th. Main NH blocking regions are forecast to be from The NE Pacific to the Kara.

 

I like it.....Omega look on that map. Question......does that ridge qualify as being in the NAO region? Or is it too far displaced S and E being more of a WAR? With that said, what are the implications of the NAO/WAR feature being located in that region irt potential storm tracks verbatim?

It looks just like the 13-14 winter 500 mb pattern pushed a bit further east. The main action that winter was very high ratio Arctic waves and SWFE's. So perhaps a version of that will occur at some point in December.

http://mp1.met.psu.edu/~fxg1/NARR/2013/us1214.php

http://mp1.met.psu.edu/~fxg1/NARR/2014/us0121.php

 

 

[nrgjeff]

Interesting break-down between 4" and 10" events for NYC. I figure the -AO gives good 4" stats due to cold. The +PNA can bring the 10" goods due to a strong trough in the Mississippi Valley, leading to a true Miller A, so long as the track is right and NYC avoids coastal front heart break. Good stuff as always Don!

1 hour ago, donsutherland1 said:

Since confidence in the development of large-scale, long-duration blocking is high, below is a chart depicting the distribution of New York City's 4" or greater snowstorms in December (1950-2016) based on the state of the AO and PNA.

Since 1950, there have been 24 such snowstorms. 6 or 25% brought 10" or more snow. The AO-/PNA+ dual blocking accounted for 50% of those storms. Even as the AO was more important that the state of the PNA when it came to the frequency of 4" or more snowstorms, the PNA was the principal factor when it came to 10" or greater snowstorms, with the PNA+ being present for 83% of such storms.