How Important Is The -NAO For Top 10 Snowstorms?

[bluewave]

I put together a collection of the top 10 snowstorms from Newark to Islip since 1950. This is when the NAO data became regularly available. Nearly all the events at our 5 major climate sites occurred following a -NAO. The lowest NAO readings were included up to 10 days before the events. The few exceptions to the pattern were in 2013,2015, and January 1978. February 2013 featured a very strong STJ following the early El Nino development which faded out in the fall. January 2015 and 1978 were during a weak El Nino. So on a few occasions the strong STJ was able to overcome the +NAO. Also notice how many storms have happened during our recent historic run.

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

NYC

27.5...1-24-16....-0.890

26.9...2-12-06....-0.537

20.9...2-26-10....-1.299

20.2..1-8-96......-.1.719

20.0...12-27-10...-1.533

19.8...2-17-03...+0.654

19.0...1-27-11....-0.944

17.7...2-7-78.....-0.865

17.6...2-12-83...-0.690

17.4...2-4-61.....-0.126

EWR

27.8...1-8-96.....-1.719

24.3...1-23-16....-0.890

24.2...12-27-10..-1.533

22.6...2-4-61......-0.126

22.3...2-17-03....+0.654

21.3..2-12.-06....-0.537

20.4...12-12-60...-0.078

19.0...2-7-78......-0.865

18.9...1-27-11...-0.944

18.2...3-19-56...-0.225

JFK

30.5...1-24-16...-0.890

25.8...2-17-03...+0.654

24.1...2-4-61....-0.126

21.7...2-12-83...-0.690

20.7...1-8-96....-1.719

20.2...2-10-69...-0.678

18.1...2-5-61....-0.126

16.7...2-12-06...-0.537

15.6...12-27-10...-1.533

14.5...12-20-09...-2.111

LGA

28.2...1-24-16...-0.890

25.4...2-12-06...-0.537

23.8...1-8-96...-1.719

22.0...2-12-83...-0.690

19.0...2-5-61...-0.126

17.3...1-27-11...-0.944

16.5...2-17-03..+0.654

16.1...2-10-69...-0.678

15.3...3-4-60....-1.095

14.9...12-20-95..-1.581

ISP

27.8...2-9-13....+0.219

25.9...2-7-78....-0.865

24.9...1-27-15...+0.235

23.9...12-20-09...-2.111

23.7...1-24-16...-0.890

20.1...2-12-83...-0.690

19.9...2-12-06...-0.537

17.8..1-20-78...+0.234

17.0...1-8-96...-1.719

17.0...2-10-69...-0.678

 

 

 

[weatherpruf]

6 hours ago, bluewave said:

I put together a collection of the top 10 snowstorms from Newark to Islip since 1950. This is when the NAO data became regularly available. Nearly all the events at our 5 major climate sites occurred following a -NAO. The lowest NAO readings were included up to 10 days before the events. The few exceptions to the pattern were in 2013,2015, and January 1978. February 2013 featured a very strong STJ following the early El Nino development which faded out in the fall. January 2015 and 1978 were during a weak El Nino. So on a few occasions the strong STJ was able to overcome the +NAO. Also notice how many storms have happened during our recent historic run.

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

NYC

27.5...1-24-16....-0.890

26.9...2-12-06....-0.537

20.9...2-26-10....-1.299

20.2..1-8-96......-.1.719

20.0...12-27-10...-1.533

19.8...2-17-03...+0.654

19.0...1-27-11....-0.944

17.7...2-7-78.....-0.865

17.6...2-12-83...-0.690

17.4...2-4-61.....-0.126

EWR

27.8...1-8-96.....-1.719

24.3...1-23-16....-0.890

24.2...12-27-10..-1.533

22.6...2-4-61......-0.126

22.3...2-17-03....+0.654

21.3..2-12.-06....-0.537

20.4...12-12-60...-0.078

19.0...2-7-78......-0.865

18.9...1-27-11...-0.944

18.2...3-19-56...-0.225

JFK

30.5...1-24-16...-0.890

25.8...2-17-03...+0.654

24.1...2-4-61....-0.126

21.7...2-12-83...-0.690

20.7...1-8-96....-1.719

20.2...2-10-69...-0.678

18.1...2-5-61....-0.126

16.7...2-12-06...-0.537

15.6...12-27-10...-1.533

14.5...12-20-09...-2.111

LGA

28.2...1-24-16...-0.890

25.4...2-12-06...-0.537

23.8...1-8-96...-1.719

22.0...2-12-83...-0.690

19.0...2-5-61...-0.126

17.3...1-27-11...-0.944

16.5...2-17-03..+0.654

16.1...2-10-69...-0.678

15.3...3-4-60....-1.095

14.9...12-20-95..-1.581

ISP

27.8...2-9-13....+0.219

25.9...2-7-78....-0.865

24.9...1-27-15...+0.235

23.9...12-20-09...-2.111

23.7...1-24-16...-0.890

20.1...2-12-83...-0.690

19.9...2-12-06...-0.537

17.8..1-20-78...+0.234

17.0...1-8-96...-1.719

17.0...2-10-69...-0.678

 

 

 

From what I see here, in central NJ, we need a neg NAO for a big storm. The storms that were not during that phase busted here but delivered to CT and LI. Seems clear evidence to me. Of course, anything is possible I guess.

[Paragon]

6 hours ago, bluewave said:

I put together a collection of the top 10 snowstorms from Newark to Islip since 1950. This is when the NAO data became regularly available. Nearly all the events at our 5 major climate sites occurred following a -NAO. The lowest NAO readings were included up to 10 days before the events. The few exceptions to the pattern were in 2013,2015, and January 1978. February 2013 featured a very strong STJ following the early El Nino development which faded out in the fall. January 2015 and 1978 were during a weak El Nino. So on a few occasions the strong STJ was able to overcome the +NAO. Also notice how many storms have happened during our recent historic run.

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

NYC

27.5...1-24-16....-0.890

26.9...2-12-06....-0.537

20.9...2-26-10....-1.299

20.2..1-8-96......-.1.719

20.0...12-27-10...-1.533

19.8...2-17-03...+0.654

19.0...1-27-11....-0.944

17.7...2-7-78.....-0.865

17.6...2-12-83...-0.690

17.4...2-4-61.....-0.126

EWR

27.8...1-8-96.....-1.719

24.3...1-23-16....-0.890

24.2...12-27-10..-1.533

22.6...2-4-61......-0.126

22.3...2-17-03....+0.654

21.3..2-12.-06....-0.537

20.4...12-12-60...-0.078

19.0...2-7-78......-0.865

18.9...1-27-11...-0.944

18.2...3-19-56...-0.225

JFK

30.5...1-24-16...-0.890

25.8...2-17-03...+0.654

24.1...2-4-61....-0.126

21.7...2-12-83...-0.690

20.7...1-8-96....-1.719

20.2...2-10-69...-0.678

18.1...2-5-61....-0.126

16.7...2-12-06...-0.537

15.6...12-27-10...-1.533

14.5...12-20-09...-2.111

LGA

28.2...1-24-16...-0.890

25.4...2-12-06...-0.537

23.8...1-8-96...-1.719

22.0...2-12-83...-0.690

19.0...2-5-61...-0.126

17.3...1-27-11...-0.944

16.5...2-17-03..+0.654

16.1...2-10-69...-0.678

15.3...3-4-60....-1.095

14.9...12-20-95..-1.581

ISP

27.8...2-9-13....+0.219

25.9...2-7-78....-0.865

24.9...1-27-15...+0.235

23.9...12-20-09...-2.111

23.7...1-24-16...-0.890

20.1...2-12-83...-0.690

19.9...2-12-06...-0.537

17.8..1-20-78...+0.234

17.0...1-8-96...-1.719

17.0...2-10-69...-0.678

 

 

 

Chris, changing from one phase to the other is probably the most important factor.

Didn't PD2 occur during a +NAO? But it had switched just a few days before the storm?

2002-03 wasn't a very NEG NAO winter was it?  But we had many switches between phases, which is what made it so stormy.

[bluewave]

44 minutes ago, weatherpruf said:

From what I see here, in central NJ, we need a neg NAO for a big storm. The storms that were not during that phase busted here but delivered to CT and LI. Seems clear evidence to me. Of course, anything is possible I guess.

Yeah, PHL was similar to the NYC Metro and LI stations. The only top 10 snowstorm without a -NAO since 1950 was PD2.

PHL

31.0...1-8-96.....-1.719

28.5...2-6-10......-0.985

23.2..12-20-09...-2.111

22.4...1-24-16....-0.890

21.3...2-12-83....-0.690

18.7...2-17-03...+0.654

15.8...2-12-06...-0.537

15.1..1-27-11...-0.944

14.6..12-12-60..-0.078

14.3...2-19-79...-0.633

[bluewave]

43 minutes ago, Paragon said:

Chris, changing from one phase to the other is probably the most important factor.

Didn't PD2 occur during a +NAO? But it had switched just a few days before the storm?

2002-03 wasn't a very NEG NAO winter was it?  But we had many switches between phases, which is what made it so stormy.

Yeah, we have had top 10 storms near the changes and in the middle of -NAO events. 2002-2003 was interesting in that the -NAO was mostly front-loaded into December and the first week of January. PD2 was unique since it occurred during a +NAO run that began during the second week of January. But we had the El Nino STJ along with a strong -EPO block.

[Paragon]

2 minutes ago, bluewave said:

Yeah, we have had top 10 events near the changes and in the middle of -NAO events. 2002-2003 was interesting in that the -NAO was mostly front-loaaded into December and the first week of January. PD2 was unique in that it occurred during a +NAO run that began during the second week of January. But we had the El Nino STJ along with a strong -EPO block.

That's right and we had a pretty significant storm before PD2 but it gets lost because of the historic nature of what came after.  The Pre-PD2 storm dumped 9 inches of snow, I think?

What did we have for the April 2003 snowstorm?  -NAO? That was another big one, I would consider it historic for us in Nassau County considering it was April.

 

[bluewave]

6 minutes ago, Paragon said:

That's right and we had a pretty significant storm before PD2 but it gets lost because of the historic nature of what came after.  The Pre-PD2 storm dumped 9 inches of snow, I think?

What did we have for the April 2003 snowstorm?  -NAO? That was another big one, I would consider it historic for us in Nassau County considering it was April.

 

That April 2003 snowstorm happened just a few days after a brief -NAO drop.

[uncle W]

the pna is just as important...the only storm I found with a negative pna that was 8" plus from DCA to Boston was the March 1960 storm...

[Paragon]

2 hours ago, bluewave said:

That April 2003 snowstorm happened just a few days after a brief -NAO drop.

I think the Xmas 2002 storm also had a neg nao? That was a nice surprise for us.

[Eduardo]

4 hours ago, bluewave said:

Yeah, we have had top 10 storms near the changes and in the middle of -NAO events. 2002-2003 was interesting in that the -NAO was mostly front-loaded into December and the first week of January. PD2 was unique since it occurred during a +NAO run that began during the second week of January. But we had the El Nino STJ along with a strong -EPO block.

Much different synoptic setup than our typical blockbusters too.  Wasn't PDII essentially just a humongous overrunning event?

[AfewUniversesBelowNormal]

It would be cool to see a larger sample size, and also time of year. My guess is NAO is very important for NYC, 2:1 to 3:1 for snow. 

[SnoSki14]

PD II is one unique way to get a big storm in this coming pattern. There's definitely support building from the 27-30th for a big overrunning storm.

+NAO/-PNA but with a strongly -EPO/WPO. Could be interesting.

[bluewave]

While it's still mostly -NAO, the storms that just missed the top ten since 2000 in NYC included 3 +NAO events. These were the 10-14 inch snowfalls.

14.0...12-6-03...-0.197

13.8...1-23-05...+0.204

13.3..1-26-11...-9.444

12.5...2-14-14...+0.680

12.0...12-31-00...-1.227

11.5...1-22-14...-0.529

11.4...2-9-13...+0.219

10.9...12-20-09...-2.111

10.3...1-28-04...-1.449

10.0...2-11-10..-1.202

[bluewave]

With the 6 to just under 10 inch storms in NYC since 2000, there was an increase to 5-6 +NAO storms. 

9.8...1-27-15...+0.235

9.4...2-10-17...+0.290

9.1...1-12-11....-1.909

8.3...3-2-09...+0.502

8.0...2-4-14...+0.246

7.7...3-1-05...-1.379

7.6...3-15-17...-0.164...note...the NAO was only briefly negative and mostly positive before the storm...This allowed the record snowfall for the interior but not the coast

7.5...3-6-15...+0.619

6.3...1-7-17...-0.774

6.0...2-23-08...-0.422

6.0...2-25-05...-1.379

6.0...12-6-02...-1.385

6.0...1-22-01...-0.438

 

[bluewave]

18 hours ago, Eduardo said:

Much different synoptic setup than our typical blockbusters too.  Wasn't PDII essentially just a humongous overrunning event?

Yeah, it was a long duration overrunning event. Great combination of El Nino STJ and -EPO generated very strong Arctic high to our north. 

[Paragon]

1 hour ago, bluewave said:

Yeah, it was a long duration overrunning event. Great combination of El Nino STJ and -EPO generated very strong Arctic high to our north. 

Wasn't Feb 1983 the same thing?

 

Those are our biggest storms!

 

[Paragon]

20 hours ago, AfewUniversesBelowNormal said:

It would be cool to see a larger sample size, and also time of year. My guess is NAO is very important for NYC, 2:1 to 3:1 for snow. 

There are some outlier winters like 1993-94

[Stormlover74]

36 minutes ago, Paragon said:

Wasn't Feb 1983 the same thing?

 

Those are our biggest storms!

 

Pretty sure 83 was a coastal.

Would love a Feb 94 repeat

[Paragon]

5 minutes ago, Stormlover74 said:

Pretty sure 83 was a coastal.

Would love a Feb 94 repeat

Both, right, back to back?

I mean PD2 was a coastal too, I think both were part overrunning and part coastal, that's why they lasted for two days lol.

 

[Stormlover74]

14 minutes ago, Paragon said:

Both, right, back to back?

I mean PD2 was a coastal too, I think both were part overrunning and part coastal, that's why they lasted for two days lol.

 

83 was relatively quick I think. About 18-24 hours

[forkyfork]

bump