November 2020 General Discussions & Observations Thread

[mattinpa]

27 minutes ago, snowman19 said:

Yea, the Euro weeklies are very ugly through the end of December and there’s no reason to doubt them at this point in time, I think there’s reason to be optimistic about January though

Indeed. At THIS point of time, but they could still change. Hope you are right that we get at least one good month.

[KEITH L.I]

54 minutes ago, bluewave said:

The latest weeklies are +EPO, +NAO and SE Ridge through the end of December.

Just click select dimensions to get the North America maps.

https://apps.ecmwf.int/webapps/opencharts/products/extended-anomaly-z500?base_time=202011160000&projection=opencharts_europe&valid_time=202011230000

 

Out past 3 weeks is not that accurate on the weeklies since I've been following them

[bluewave]

40 minutes ago, KEITH L.I said:

Out past 3 weeks is not that accurate on the weeklies since I've been following them

I usually don’t pay that much attention to the weeklies past the first week or two. But they match up with past Novembers that averaged 50° or warmer in NYC. 7 out of 9 years  since 1990 had a near 40°or warmer December. Most years were El Niño or neutral. But 2011 and 1999 were La Niña years.

Monthly Mean Avg Temperature for NY CITY CENTRAL PARK, NY
Click column heading to sort ascending, click again to sort descending.

Year	Nov	Dec
2020	56.3	M
2015	52.8	50.8
2001	52.7	44.1
2011	51.9	43.3
2006	51.9	43.6
1994	51.9	42.2
2009	51.1	35.9
1999	50.8	39.9
1990	50.3	42.6
2003	50.0	37.6

 

[donsutherland1]

Under bright sunshine, temperatures rose into the lower and middle 50s across the region.

Out west, Phoenix reached 92° today. That broke the daily record of 89°, which was set in 1999. It was also the latest 90° or above temperature on record for Phoenix. The previous record was 90°, which occurred on November 15, 2020. Records go back to 1895.

Late tonight or early tomorrow morning Hurricane Iota will make landfall near the Honduras-Nicaragua border as either a strong Category 4 or even Category 5 hurricane. It is the only Category 5 hurricane on record in the Atlantic basin during November.
 
Tomorrow through Thursday will be much cooler than normal. Temperatures will moderate afterward. Temperatures will return to mild levels afterward. November could conclude with warmer than normal temperatures. December could open with above to perhaps much above normal temperatures.

While readings will likely be colder than normal in the Middle Atlantic and southern New England areas through Thursday, it will be exceptionally warm in parts of the southwestern United States. As a result, Phoenix could see additional near-record to record high temperatures through Thursday. Phoenix could also further extend its record for its latest 90° temperature on record.

The ENSO Region 1+2 anomaly was -0.3°C and the Region 3.4 anomaly was -1.0°C for the week centered around November 11. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.98°C and the ENSO Region 3.4 anomaly has averaged -1.44°C. La Niña conditions will likely prevail at through the winter.

The SOI was +11.45.

Today, the preliminary Arctic Oscillation (AO) figure was +2.163.

On November 15 the MJO was in Phase 2 at an amplitude of 1.455 (RMM). The November 14-adjusted amplitude was 1.160.

Based on the latest guidance, no significant stratospheric warming event is likely through at least November 20. The lack of such warming could favor the gradual strengthening of the stratospheric polar vortex. A strong polar vortex could have implications for the opening of meteorological winter.

Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO. A predominant EPO+/AO+ pattern is likely for winter 2020-21. It is likely that the Middle Atlantic and southern New England areas will see a warmer than normal winter with potentially below normal snowfall. The November run of the seasonal European guidance suggests that winter 2020-21 will likely be warmer to much warmer than normal in the region.

The potential also exists for below to much below normal seasonal snowfall in the Middle Atlantic and southern New England areas. Since 1970, there were 9 winters that saw the AO and EPO average +0.25 or above. Mean snowfall for Boston, Harrisburg, New York City, Philadelphia, and Washington, DC averaged 50% of the most recent 30-season mean. The largest snowfall deficits relative to the most recent 30-season mean figure were located in the Philadelphia to New York City corridor. In addition, 33% of cases saw less than 10" seasonal snowfall in New York City and 44% saw less than 10" seasonal snowfall in Philadelphia.

Based on sensitivity analysis applied to the latest guidance, there is an implied 90% probability that New York City will have a warmer than normal November. November will likely finish with a mean temperature near 50.9°.

 

[the_other_guy]

32 minutes ago, KEITH L.I said:

Out past 3 weeks is not that accurate on the weeklies since I've been following them

That’s right. just like two weeks ago nobody was talking about the cold this week. Even in a warm month, you get some cold weeks things lineup and you make out. 

Nobody should be writing off anything beyond next week at this point

[BucksCO_PA]

1 hour ago, bluewave said:

I usually don’t pay that much attention to the weeklies past the first week or two. But they match up with past Novembers that averaged 50° or warmer in NYC. 7 out of 9 years  since 1990 had a near 40°or warmer December. Most years were El Niño or neutral. But 2011 and 1999 were La Niña years.

Monthly Mean Avg Temperature for NY CITY CENTRAL PARK, NY
Click column heading to sort ascending, click again to sort descending.

Year	Nov	Dec
2020	56.3	M
2015	52.8	50.8
2001	52.7	44.1
2011	51.9	43.3
2006	51.9	43.6
1994	51.9	42.2
2009	51.1	35.9
1999	50.8	39.9
1990	50.3	42.6
2003	50.0	37.6

 

Temp averages & trends for the Philadelphia POR, recent trends since 2010 & during the past 30 yrs. relative to average no month has warmed more than DEC. The DEC mean since 2010 is over 40 degrees, nearly 3 degrees above the current normal.

Looking at the bleak LR outlook & ISO's winter forecast I wonder if our best hope is for a JAN 2000 type scenario in which we see a solid 2-3 wk. stretch of winter & then on to a very early spring?

. 

 

[SnoSki14]

2 hours ago, Allsnow said:

 

Lol. Yep. Continue that look into January 1. Not a hint of change on them 

This year a mild snow free winter would be a good thing so I'm hoping that's the case. 

It just seems that's the type of pattern we're in since 2015. It's hard to complain given the winters since 2000 have been mostly very good. 

It'll be interesting to see if the SE ridge pattern is a mainstay due to AGW or something that lasts several years and reverts back. 

[Allsnow]

3 minutes ago, SnoSki14 said:

This year a mild snow free winter would be a good thing so I'm hoping that's the case. 

It just seems that's the type of pattern we're in since 2015. It's hard to complain given the winters since 2000 have been mostly very good. 

It'll be interesting to see if the SE ridge pattern is a mainstay due to AGW or something that lasts several years and reverts back. 

It’s amazing to see the winters of 13/14 14/15 in a sea of warmth. Those two winters feel like forever ago now 

[jm1220]

1 hour ago, SnoSki14 said:

This year a mild snow free winter would be a good thing so I'm hoping that's the case. 

It just seems that's the type of pattern we're in since 2015. It's hard to complain given the winters since 2000 have been mostly very good. 

It'll be interesting to see if the SE ridge pattern is a mainstay due to AGW or something that lasts several years and reverts back. 

The constant Nina background state and warm Atlantic keep feeding it. Until the Nina background state goes away we’ll likely keep seeing it. As others have said it can be good in certain situations by keeping storms from sliding SE of here (“Bomb cyclone” just after New Years 2018) but more often now it causes inland runners. 

[psv88]

Going to be a cold night, already 32, forecast low was 36

[CIK62]

The next 8 days are averaging 50degs.[44/55].         Making it 45degs., or just Normal.

Month to date is 55.9[+5.9].       Should be 52.3[+3.9] by the 25th.

Tropics:    13.7N  84.3W---hitting Nicaragua.

44*(46%RH) here at 6am, scattered clouds.       46* at 7am.       47* by 8am.      49* by 11am.       50* at Noon.     45* by 3pm.      43* by 6pm.      39* by 10pm.

[IrishRob17]

8 hours ago, psv88 said:

Going to be a cold night, already 32, forecast low was 36

My forecasted low when the afternoon package came out was 35, Upton adjusted to 30 last I checked around 8pm, sitting at 26 now. 

[uofmiami]

22 minutes ago, IrishRob17 said:

My forecasted low when the afternoon package came out was 35, Upton adjusted to 30 last I checked around 8pm, sitting at 26 now. 

Upton has been too warm on nights where there’s good radiational cooling.  I had lows of 29.5 in Muttontown & 30.1 in Syosset this morning. I recall last night’s forecast was 35 for morning low.

[bluewave]

11 hours ago, BucksCO_PA said:

Temp averages & trends for the Philadelphia POR, recent trends since 2010 & during the past 30 yrs. relative to average no month has warmed more than DEC. The DEC mean since 2010 is over 40 degrees, nearly 3 degrees above the current normal.

 

Similar stats for NYC with December featuring the biggest winter temperature jump in NYC since 2010.  NYC has averaged at 40.7° in December since 2011. This is +3.2° over the 1981-2010 means. The only Decembers since 2011 that averaged under 40° had a November in the 40s like we saw last year. But this hasn’t been a guarantee as several cooler Novembers like 2018, 2014, and 2012 warmed back above 40° in December.

Monthly Mean Avg Temperature for NY CITY CENTRAL PARK, NY
Click column heading to sort ascending, click again to sort descending.

Year	Nov	Dec
Mean	47.1	40.7
2019	43.9	38.3
2018	44.4	40.1
2017	46.6	35.0
2016	49.8	38.3
2015	52.8	50.8
2014	45.3	40.5
2013	45.3	38.5
2012	43.9	41.5
2011	51.9	43.3

 

[IrishRob17]

15 minutes ago, uofmiami said:

Upton has been too warm on nights where there’s good radiational cooling.  I had lows of 29.5 in Muttontown & 30.1 in Syosset this morning. I recall last night’s forecast was 35 for morning low.

I made it down to 25 for the low. I haven’t paid much attention to if they’ve been off lately but it was noticeable last evening as my temp was consistently lower than the forecast that keep getting updated. 

[MJO812]

Freeze watch in effect for NYC

[lee59]

Just now, MJO812 said:

Freeze watch in effect for NYC

I believe it hit 32 in Central Park on October 31

[donsutherland1]

Morning thoughts...

Today will be partly sunny, breezy and cool. High temperatures in the region will likely reach mainly the upper 40s and lower 50s. Likely high temperatures around the region include:

New York City (Central Park): 47°

Newark: 50°

Philadelphia: 50°

Tomorrow and Thursday will be unseasonably cold. Parts of the region will experience their lowest temperatures so far this season.

[donsutherland1]

4 minutes ago, lee59 said:

I believe it hit 32 in Central Park on October 31

It did. That was Central Park’s coldest October temperature since 1988.

[bluewave]

10 hours ago, psv88 said:

Going to be a cold night, already 32, forecast low was 36

This happens when the forecast light winds go calm instead. So The 12z MOS had a low of 35° at ISP with light winds. But the calm winds resulted in a low of 32°.

KISP   GFS MOS GUIDANCE   11/16/2020  1200 UTC                      
 DT /NOV  16/NOV  17                /NOV  18                /NOV  19 
 HR   18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00 06 12 
 N/X                    35          50          27          42    27 
 TMP  53 51 46 43 39 37 38 45 48 46 40 36 32 29 29 36 40 39 34 31 33 
 DPT  27 27 28 29 27 26 27 28 26 25 23 21 18 16 15 15 14 13 14 16 22 
 CLD  FW FW FW FW CL SC BK OV OV BK BK FW FW CL CL CL CL CL CL CL FW 
 WDR  27 27 27 27 29 28 27 27 28 31 32 31 32 31 32 32 32 32 33 32 24 
 WSP  17 15 09 09 09 07 06 11 11 13 13 14 12 11 13 17 17 14 08 02 04 

 

[wdrag]

Trace of snow showers here in Wantage NJ since 730A. mPing has some snow obs. 

[psv88]

4 minutes ago, bluewave said:

This happens when the forecast light winds go calm instead. So The 12z MOS had a low of 35° at ISP with light winds. But the calm winds resulted in a low of 32°.

KISP   GFS MOS GUIDANCE   11/16/2020  1200 UTC                      
 DT /NOV  16/NOV  17                /NOV  18                /NOV  19 
 HR   18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 21 00 06 12 
 N/X                    35          50          27          42    27 
 TMP  53 51 46 43 39 37 38 45 48 46 40 36 32 29 29 36 40 39 34 31 33 
 DPT  27 27 28 29 27 26 27 28 26 25 23 21 18 16 15 15 14 13 14 16 22 
 CLD  FW FW FW FW CL SC BK OV OV BK BK FW FW CL CL CL CL CL CL CL FW 
 WDR  27 27 27 27 29 28 27 27 28 31 32 31 32 31 32 32 32 32 33 32 24 
 WSP  17 15 09 09 09 07 06 11 11 13 13 14 12 11 13 17 17 14 08 02 04 

 

28.0 this morning. Last few mornings the cold has really overperformed here. Checked the local PWS to make sure my readings are accurate, and everything my immediate area is similar, i think this area of Commack is in a relative valley of sorts, so the wind goes calm at night

[dWave]

Some light rain and 47.

Flurries/snow showers N&W of I-287?

[STORMANLI]

19 minutes ago, psv88 said:

28.0 this morning. Last few mornings the cold has really overperformed here. Checked the local PWS to make sure my readings are accurate, and everything my immediate area is similar, i think this area of Commack is in a relative valley of sorts, so the wind goes calm at night

I concur. Almost always radiate better than KISP.  28° as well this am.

[psv88]

4 minutes ago, STORMANLI said:

I concur. Almost always radiate better than KISP.  28° as well this am.

Are you in commack as well?

[jm1220]

24 minutes ago, psv88 said:

28.0 this morning. Last few mornings the cold has really overperformed here. Checked the local PWS to make sure my readings are accurate, and everything my immediate area is similar, i think this area of Commack is in a relative valley of sorts, so the wind goes calm at night

Got down to 30.4 at my closest station. I’m in a more elevated area just E of Rt 110. My elevation is about 200’. 

[dWave]

1 hour ago, lee59 said:

I believe it hit 32 in Central Park on October 31

I think the NWS didn't consider that night sufficient enough to end the growing season throughout the 5 boros.  Just touching 32 for a few mins deep in Central Park while the sun is coming up didn't do much harm overall in NYC.  Staten Island and a few isolated neighborhoods elsewhere being the exception. 

[bluewave]

29 minutes ago, psv88 said:

28.0 this morning. Last few mornings the cold has really overperformed here. Checked the local PWS to make sure my readings are accurate, and everything my immediate area is similar, i think this area of Commack is in a relative valley of sorts, so the wind goes calm at night

This may turn out to be the best radiational cooling for such a warm November. You can notice how much warmer the max departure is than the min at ISP.

ISP

Max...+6.8

Min....+2.8

Avg....+4.8

NYC

Max...+6.8

Min...+5.1

Avg...+6.0

 

[Allsnow]

Leaves are completely down here now after Sunday nights wind storm. Definitely a few weeks earlier then normal for central nj

[bluewave]

24 minutes ago, Allsnow said:

Leaves are completely down here now after Sunday nights wind storm. Definitely a few weeks earlier then normal for central nj

This has to have been the hardest decade on record for trees around the region. It seems to have started out with the March 2010 windstorm. This was followed by the NYC macroburst and tornado in September 2010. Next was the early snowstorm in October 2011 which lead to all the power outages. Irene came next in August 2011 followed by  Sandy in October 2012. Then the numerous blizzards with downed trees at times from 2013 to 2018. Along with the fall and spring storms with high wind warnings. Out of season severe in recent years like this fall and also 2018. We also saw that bow echo in June 2019 take down numerous trees across Suffolk. Isaias caused the extensive tree damage and power outages this summer.