November 2017 Discussions & Observations Thread

[Paragon]

55 minutes ago, donsutherland1 said:

Select Record Low Temperatures for 11/11/2017:

Allentown: 18° (old record: 19°)
Atlantic City: 21° (old record: 22°)
Baltimore: 21° (tied record)
Binghamton: 14° (old record: 16°)
Boston: 23° (old record: 24°)
Bridgeport: 22° (tied record)
Mount Washington: -8° (old record: -6°)
New York City:
…JFK: 24° (old record: 28°)
…LGA: 26° (old record: 29°)
…NYC: 24° (old record: 28°)
Newark: 24° (old record: 25°)
Scranton: 16° (old record: 18°)

Note: The MOS forecast was well below the actual readings for a large number of locations.
 

Wow Baltimore was colder than us! I wonder why? And Philly and DC?

 

[qg_omega]

56 minutes ago, donsutherland1 said:

Select Record Low Temperatures for 11/11/2017:

Allentown: 18° (old record: 19°)
Atlantic City: 21° (old record: 22°)
Baltimore: 21° (tied record)
Binghamton: 14° (old record: 16°)
Boston: 23° (old record: 24°)
Bridgeport: 22° (tied record)
Mount Washington: -8° (old record: -6°)
New York City:
…JFK: 24° (old record: 28°)
…LGA: 26° (old record: 29°)
…NYC: 24° (old record: 28°)
Newark: 24° (old record: 25°)
Scranton: 16° (old record: 18°)

Note: The MOS forecast was well below the actual readings for a large number of locations.
 

I remember reading Albany in the single digits for days in the forecast

[Paragon]

2 minutes ago, qg_omega said:

I remember reading Albany in the single digits for days in the forecast

Looks like the cold air wasn't centered over our region, note how Baltimore was 3 degrees colder than us.

This reminds me of the January 2004 arctic shot, which was centered to our east- we were forecast to go below zero twice, and got down to 1 degree both nights.

 

[donsutherland1]

5 hours ago, Paragon said:

That 1986 cold shot must've been amazing Don, their earliest -10 and -15 temp too?  What low did NYC have that morning?

 

 

November 1986 saw two cold waves, with the first being the most impressive. Below are the low temperatures for NYC:

11/13/86 24°
11/14/86 22°
11/15/86 29°

11/19/86 27°
11/20/86 26°
 

[Paragon]

2 minutes ago, donsutherland1 said:

November 1986 saw two cold waves, with the first being the most impressive. Below are the low temperatures for NYC:

11/13/86 24°
11/14/86 22°
11/15/86 29°

11/19/86 27°
11/20/86 26°
 

ah 11/14/86 must've been our earliest 22 degree reading!

 

any snow with either shot?

I wonder if we will get a similar pattern this month with two arctic shots but the later one not being as extreme.

 

Funny a year before that in 1985 we set a record high of 73 on 11/10 (yesterday.)

 

 

[bluewave]

26 minutes ago, Paragon said:

I wonder how cold this airmass would have been in late January or early February?

It would have been on par with 2-14-16. Since NYC surpassed the record low by 3 then and 4 today. So a reading a few degrees below 0. This was the first daily record low temperature in NYC for November since 1976. But NYC scored a rare two record lows in a row this time around.

[psv88]

Green leaves still on the trees. 

[gravitylover]

2 minutes ago, psv88 said:

Green leaves still on the trees. 

Funny you say that, I was just looking out and realized that a couple of trees just below my house are still green, light fall green but green nonetheless. 

I was up in the woods yesterday between 1100-1250 feet and it's definitely stick season up there. Some of the scrub oak is still full color but it's warmer the closer to the ground you get so that makes sense and some of the birch and beech trees are holding on to their leaves but they're crispy and it's just a matter of time before they fall off. Basically the forest is transitioning right on schedule around here.

[Paragon]

14 minutes ago, bluewave said:

It would have been on par with 2-14-16. Since NYC surpassed the record low by 3 then and 4 today. So a reading a few degrees below 0. This was the first daily record low temperature in NYC for November since 1976. But NYC scored a rare two record lows in a row this time around.

Wait, the 22 recorded on 11/14/86 wasn't a record?  I thought that was the earliest 22 NYC has recorded.

 

[Paragon]

5 minutes ago, gravitylover said:

Funny you say that, I was just looking out and realized that a couple of trees just below my house are still green, light fall green but green nonetheless. 

I was up in the woods yesterday between 1100-1250 feet and it's definitely stick season up there. Some of the scrub oak is still full color but it's warmer the closer to the ground you get so that makes sense and some of the birch and beech trees are holding on to their leaves but they're crispy and it's just a matter of time before they fall off. Basically the forest is transitioning right on schedule around here.

I think the fall foliage is like 2 weeks behind schedule.  We should have peaked about a week or two ago around here.

[donsutherland1]

2 hours ago, Paragon said:

Problem is long range forecasting is so hit and miss.  Earlier we were talking about the possibility of a record warm November.  Now we're talking about cold.  Also, I heard about the possibility of a mild pattern starting early December.  When I talk to other people about it, they say long range forecasting has zero credibility.  "Weren't they saying it's going to be a warm November and now look what's happened.  I don't believe them when they say it's going to get milder in December, no one knows how to forecast more than a few days ahead, it's a total crapshoot, and I don't believe them," is what they say.

 

I agree.

While the guidance has improved with monthly departures from normal, it still isn't great. Weekly forecasting, especially beyond two weeks is still not much better than climatology. Even where things now stand, the implied probability is around 60% for a below normal November (when sensitivity analysis, which relies on assumptions about types of outcomes, is applied), leaving plenty of room for a warmer outcome. The implied probability for a mean temperature of 47° or below is 53%. As of yesterday, November's mean temperature was 51.5°. By the 20th, the likely range is between 46.8° and 48.6°.

Perhaps reflecting how quickly things can sometimes change, the spread among ensemble members for the Arctic Oscillation has widened substantially in the past day. While some members still show extreme values, others take the AO to just below -2.000. Depending on how things play out, there could be big implications for the close of November and perhaps beyond. Even if severe blocking develops, once it fades, a sustained warmer pattern for much of December still could not be ruled out as happened in 1959. That's still not the most likely scenario (the Euro forecast favors a colder outcome), but it is within the realm of possibility. Of course, blocking returned in late December 1959 and the winter wound up being a snowy one. 

[bluewave]

4 minutes ago, Paragon said:

Wait, the 22 recorded on 11/14/86 wasn't a record?  I thought that was the earliest 22 NYC has recorded.

 

Those were 2nd coldest records behind earlier years in 86.

11/14

20 in 1905

22 in 1986

22 in 1873

[gravitylover]

Just now, Paragon said:

I think the fall foliage is like 2 weeks behind schedule.  We should have peaked about a week or two ago around here.

I think that the soil temp is quite a bit higher in the residential areas around here so the trees take longer to turn. Whether that's the real reason or not I don't know but it sounds good so I'm going with it  

[Paragon]

Just now, donsutherland1 said:

I agree.

While the guidance has improved with monthly departures from normal, it still isn't great. Weekly forecasting, especially beyond two weeks is still not much better than climatology. Even where things now stand, the implied probability is around 60% for a below normal November (when sensitivity analysis, which relies on assumptions about types of outcomes, is applied), leaving plenty of room for a warmer outcome. The implied probability for a mean temperature of 47° or below is 53%. As of yesterday, November's mean temperature was 51.5°. By the 20th, the likely range is between 46.8° and 48.6°.

Perhaps reflecting how quickly things can sometimes change, the spread among ensemble members for the Arctic Oscillation has widened substantially in the past day. While some members still show extreme values, others take the AO to just below -2.000. Depending on how things play out, there could be big implications for the close of November and perhaps beyond. Even if severe blocking develops, once it fades, a sustained warmer pattern for much of December still could not be ruled out as happened in 1959. That's still not the most likely scenario (the Euro forecast favors a colder outcome), but it is within the realm of possibility. Of course, blocking returned in late December 1959 and the winter wound up being a snowy one. 

I find that when the pattern has been a certain way for a long time, the models have a tough time ascertaining when it's going to change.  September and October were so warm, and November has been radically different.

1959-60 was a classic bookend winter!

 

[Paragon]

1 minute ago, bluewave said:

Those were 2nd coldest records behind earlier years.

Oh I see, so 11/14 was the earliest NYC has reached 22, but a previous year got even lower on the same date?

 

[Paragon]

1 minute ago, donsutherland1 said:

Yes, the 22° reading was NYC's earliest on record. However, November 15, 1933 had a temperature of 18°.

There was no measurable snowfall during the two November 1986 Arctic outbreaks. The first snowfall occurred in December. 

11/15/1933 must've been our earliest teens reading- 1933-34 was a winter of epic records and big snows in both November and February.  Very similar to 1898-1899 in that respect.

 

[donsutherland1]

5 minutes ago, Paragon said:

Oh I see, so 11/14 was the earliest NYC has reached 22, but a previous year got even lower on the same date?

 

I deleted the erroneous post. I had pasted data from wrong station: 

The NYC figures are:

11/13 22°, 1873 (earliest 22°)

11/14 20°, 1905 (earliest 21° or below)

11/16 17°, 1933 (earliest below 20°)

I regret the error, as I thought I had Central Park loaded.

[JerseyWx]

Stayed at 20° last night.  Wouldn't budge for hours.

[bluewave]

3 hours ago, Paragon said:

Problem is long range forecasting is so hit and miss.  Earlier we were talking about the possibility of a record warm November.  Now we're talking about cold.  Also, I heard about the possibility of a mild pattern starting early December.  When I talk to other people about it, they say long range forecasting has zero credibility.  "Weren't they saying it's going to be a warm November and now look what's happened.  I don't believe them when they say it's going to get milder in December, no one knows how to forecast more than a few days ahead, it's a total crapshoot, and I don't believe them," is what they say.

 

The problem is that the longer range ensemble extensions beyond 6-10 and 11-15 days aren't good at detecting pattern changes. In a stable pattern the weeklies can have some value beyond week 2. The record MJO wave in late October only really showed up in the short term. Models had to play catch up with the magnitude as the event was occurring.

[Rjay]

3 hours ago, EasternLI said:

Thanks for pointing that out. I'll be mindful of that in the future. Didn't double check FTL.

26F here at this attm.

Np.  Made it down to 24 in my neck of the woods.  Spent most of the night at 25 degrees. 

[uncle W]

the cold wave of mid November 1967 behaved in similar fashion...the temp was 20 at midnight and that was the low for both days...67 is one of the analogs on my list...there was a snowfall on Nov. 30th 1967...3" fell in the city...7" fell well south of us...

[Paragon]

18 minutes ago, donsutherland1 said:

I deleted the erroneous post. I had pasted data from wrong station: 

The NYC figures are:

11/13 22°, 1873 (earliest 22°)

11/14 20°, 1905 (earliest 21° or below)

11/16 17°, 1933 (earliest below 20°)

I regret the error, as I thought I had Central Park loaded.

Thanks, Don, that clears things up!

 

[Paragon]

16 minutes ago, bluewave said:

The problem is that the longer range ensemble extensions beyond 6-10 and 11-15 days aren't good at detecting pattern changes. In a stable pattern the weeklies can have some value beyond week 2. The record MJO wave in late October only really showed up in the short term. Models had to play catch up with the magnitude as the event was occurring.

Thanks, Chris, that's what I suspected- they were just forecasting a continuation of the pattern that had been in place since early September.

[Rjay]

FRG also made it down to 24. 

[snywx]

15° for a low this morning

[Cfa]

The leaves on my banana tree(s) are finished, but the stems are still firm and vibrant green. That tells me that I likely didn’t experience a hard freeze here since they would’ve turned to a discolored mush. Elephant Ears are toast. Palms are untouched. Trees look the way they did yesterday.

Above freezing now.

[sferic]

Is there a histogram for SST? Be interesting to see how the ocean reacted to this abrupt cold spell the past 24 hours.

[bluewave]

13 minutes ago, Paragon said:

Thanks, Chris, that's what I suspected- they were just forecasting a continuation of the pattern that had been in place since early September.

We have been seeing in the 2010's how quickly these extreme blocking events can change up a pattern. This is a new blocking record for the Aleutians during the first week of November. A +400 meter anomaly is as impressive as it gets for a whole week in that area.

 

 

 

[uncle W]

56 minutes ago, donsutherland1 said:

I agree.

While the guidance has improved with monthly departures from normal, it still isn't great. Weekly forecasting, especially beyond two weeks is still not much better than climatology. Even where things now stand, the implied probability is around 60% for a below normal November (when sensitivity analysis, which relies on assumptions about types of outcomes, is applied), leaving plenty of room for a warmer outcome. The implied probability for a mean temperature of 47° or below is 53%. As of yesterday, November's mean temperature was 51.5°. By the 20th, the likely range is between 46.8° and 48.6°.

Perhaps reflecting how quickly things can sometimes change, the spread among ensemble members for the Arctic Oscillation has widened substantially in the past day. While some members still show extreme values, others take the AO to just below -2.000. Depending on how things play out, there could be big implications for the close of November and perhaps beyond. Even if severe blocking develops, once it fades, a sustained warmer pattern for much of December still could not be ruled out as happened in 1959. That's still not the most likely scenario (the Euro forecast favors a colder outcome), but it is within the realm of possibility. Of course, blocking returned in late December 1959 and the winter wound up being a snowy one. 

I'll sign up for a December like 1959...6-14" of snow fell around the city on 12/22...8" fell in Brooklyn...the coldest temperature of the winter followed and snow was on the ground Christmas morning...

[LongBeachSurfFreak]

12 hours ago, LongBeachSurfFreak said:

Y

 

Ohh I know allllll about it. Hey well see. I was just making the point that the CAA likely peaked during the day light hours. It’s so freakin early the sun is still relatively strong. Just look at the mt Washington obs from today the cold air was aloft during the day 

Sorry to do this guys but I got called out. Nailed the low temp in the park with 24. CAA did peak during the day yesterday. That’s what prevented temps from reaching the MOS and NWS forecasts. The city just doesn’t radiate and thus relys on fresh cold air being funneled in. Once that had peaked (in the afternoon) temps stabilized.

it was still an impresive event.

My veggie garden went from still producing tomatoes, peppers and eggplant to completely fried. The eggplant especially which were massive are shriveled!