September 2021

[bluewave]

It looks like NYC may finally drop below 55° next week. HPN could also see the first 40s of the fall. This would be very late for these temperature benchmarks at both stations. 
 

Latest first day below 55° in NYC

First/Last Summary for NY CITY CENTRAL PARK, NY
Each section contains date and year of occurrence, value on that date.
Click column heading to sort ascending, click again to sort descending.

Year	Last	Value	First	Value	Difference
2015	06-04 (2015)	54	10-02 (2015)	48	119
1910	06-08 (1910)	53	10-02 (1910)	54	115
1921	06-05 (1921)	54	10-01 (1921)	52	117
1908	05-16 (1908)	53	09-30 (1908)	52	136
2005	06-02 (2005)	54	09-29 (2005)	54	118
2003	06-17 (2003)	53	09-29 (2003)	53	103
2002	06-08 (2002)	53	09-29 (2002)	54	112
1968	06-21 (1968)	53	09-29 (1968)	53	99
1930	06-01 (1930)	50	09-29 (1930)	53	119
1970	05-30 (1970)	50	09-27 (1970)	54	119
2016	06-09 (2016)	54	09-25 (2016)	54	107

Latest first 40s at HPN

 

First/Last Summary for WESTCHESTER CO AP, NY
Each section contains date and year of occurrence, value on that date.
Click column heading to sort ascending, click again to sort descending.

Year	Last	Value	First	Value	Difference
2018	06-12 (2018)	49	10-12 (2018)	47	121
2017	06-09 (2017)	47	09-29 (2017)	47	111
2002	06-08 (2002)	48	09-29 (2002)	48	112
1970	05-30 (1970)	44	09-29 (1970)	42	121
1968	05-28 (1968)	46	09-29 (1968)	49	123
2005	05-25 (2005)	46	09-28 (2005)	46	125
2015	06-02 (2015)	48	09-27 (2015)	47	116
1980	06-14 (1980)	47	09-27 (1980)	44	104
2016	05-21 (2016)	48	09-25 (2016)	44	126

[CIK62]

What is going on here on the EURO?         The area that is hanging back from SAM  'hangs on' for at least 72 hours of 40mph gusts{from N} near here, starting at 168hrs.(not shown)     The GFS and CMC have this is in a minor way only.

 

[donsutherland1]

Tomorrow and Monday will be fair and pleasantly warm days. Afterward, a cold front could bring some showers or thundershowers to the region on Tuesday.

The MJO had recently been locked in Phase 3 at a high amplitude, frequently in excess of 1.500. Only 2006 and 2009 saw the MJO in Phase 3 at an amplitude of 1.500 or above for 2 or more days during September 10-20. Both years saw September end with a cold shot that continued into the first days of October. Both days saw Central Park's temperature fall to 49° on September 30. The guidance has now come into better agreement concerning a cool shot to end the month. Afterward, in the MJO cases, a fairly sharp rebound in temperatures followed. October wound up wetter than normal with 7.07" rainfall in 2006 and 5.58" of rainfall in 2009. Normal rainfall (1991-2020) is 4.38".

2021 remains on course to become the 6th out of the last 7 years during which September has had a mean temperature of 70° or above in New York City. Prior to 2000, New York City saw such warmth on average once every five years. In short, September has become more an extension of summer than a gateway to autumn in the New York City area.

There is increasing consensus on the long-range guidance that October will be an unseasonably warm month. The first half could feature much above normal readings in the Northern Plains into Central Canada.

Fall 2021 will likely be wetter to much wetter than normal in the northern Middle Atlantic region. Since 1869, there have been 9 August cases where New York City picked up 20.00" or more rainfall during the summer. Two thirds of those cases (and 4/5 of those with summer mean temperatures of 73.0° or above) had 17.00" or more fall precipitation in New York City. 2011 is probably the closest match in terms of precipitation and a nearly identical summer mean temperature. Mean fall precipitation for those 9 cases was 14.86". The median was 17.35". The 1991-2020 normal value is 12.27".

The ENSO Region 1+2 anomaly was +0.2°C and the Region 3.4 anomaly was -0.4°C for the week centered around September 15. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.03°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral ENSO conditions will likely prevail through September. Afterward, La Niña conditions could begin to develop.

The SOI was -15.92 today.

The preliminary Arctic Oscillation (AO) figure was +0.142 today.

On September 23 the MJO was in Phase 4 at an amplitude of 0.946 (RMM). The September 22-adjusted amplitude was 1.305 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 89% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 70.4° (1.2° above normal).

 

[SACRUS]

9/25

EWR: 79
New Brnswck: 78
BLM: 77
LGA: 77
ACY: 77
JFK: 76
TTN: 76
ISP: 76
TEB: 76
PHL: 76
NYC: 75

[donsutherland1]

Under partly sunny skies with temperatures in the 70s, it was another fine late September beach day.

 

[CIK62]

The last 5 days of September are averaging 67(60/75), or +2.

Month to date is  71.4[+1.2].        September should end near  70.7[+1.5].

Today:  72-77, w.,nw. wind-gusty, p. sunny.

Reached 77* here yesterday.

Oct. 3-10 looking continuously gusty here.

Bermuda wiped out next Sat. PM?

62*(76%RH) here at 6am, scattered clouds.      64* at 9am.        67* at Noon.       68* at 1pm.        70* at 2pm.      73* at 4pm.    Reached 74* at 5:30pm.

[wdrag]

13 hours ago, Rtd208 said:

I can honestly see it being pretty quiet weather wise over the next couple of weeks outside of a couple of minor events and anything tropical that could impact us. We'll see.

Probably correct. I still think modeling is separating streams. I think  by tomorrow morning we'll know if the dry quiet is correct.  Right now, I'm unconvinced.

[bluewave]

This coming week is another example of needing record blocking to get below normal temperatures in our area.

 

[donsutherland1]

Morning thoughts…

Today will be mostly sunny and pleasantly warm. High temperatures will likely reach the lower and middle 70s in most of the region. Likely high temperatures around the region include:

New York City (Central Park): 73°

Newark: 77°

Philadelphia: 75°

Normals:

New York City: 30-Year: 72.3°; 15-Year: 73.5°

Newark: 30-Year: 73.8°; 15-Year: 75.2°

Philadelphia: 30-Year: 75.1°; 15-Year: 76.3°

Tomorrow will be a very warm day.

[SACRUS]

52 last night after a high of 80 yesterday.  On the way to mid/upper 70s.  Mon (9/27) and Tue (9/28) look like the warmest for potentially (the year) with highs 80/ low 80s in the warmer spots. Not to say it wont warm up which it looks likely by Oct 6, but dont think we exceed Mon/Tue maxes till spring. 

  Front come sthrough Tue later so clouds could spoil the warmest readings on Tuesday.   ECM /  GFS cutt ULL ville 9/29 and on but keep the brunt of the rain north of the area.  Cooler shot by Thu (9/30) - Sun (10/3) as ULL pulls down N/NNW flow.  Once we clear the ULL towards the first full week of Oct, ridging looks to rebuild into the east and warm things up.   GFS would have California style weather (overall) the next 10 days but I suspect we see clouds and rain chances with the ULL and stalled up pattern evolve.

[SACRUS]

Another marvelous day today

 

https://cdn.star.nesdis.noaa.gov//GOES16/ABI/SECTOR/EUS/GEOCOLOR/GOES16-EUS-GEOCOLOR-1000x1000.gif

[MJO812]

1 hour ago, bluewave said:

This coming week is another example of needing record blocking to get below normal temperatures in our area.

 

Luckily Sam is going OTS 

[the_other_guy]

13 hours ago, lee59 said:

It seems in my area this season, we get very heavy rain over a 24 hour period and then very little or nothing for the next 2-3 weeks.

Its insanity.

Every rain storm does damage to my property.

Limbs down, small mudslides, leaves everywhere. I redid my patio in the spring and its already a mess.

 

 

 

[MJO812]

[rclab]

1 hour ago, MJO812 said:

Good afternoon Anthony. It’s my hope that they’ll be used to plow snow instead of salt. As always ….

[Stormlover74]

After a morning low of 63 ewr records its 15th straight above normal day. Tomorrow should add another 80 to its tally

Wednesday thru Saturday looks like the first legit shot at below normal temps with expected highs around 70

[bluewave]

3 hours ago, MJO812 said:

Just in time for this new Euro extended range product.

 

 

 

[MJO812]

2 hours ago, bluewave said:

Just in time for this new Euro extended range product.

 

 

 

No october snow please 

[lee59]

Looks like mid week could have some of the chilliest temps of the new season. NWS keeps dropping the projected lows. After a low last night of 57 here only climbed to 73 today, now down to 69.

[the_other_guy]

Today is the first fall-feel day.

[RippleEffect]

6 hours ago, MJO812 said:

I don’t get it I saw one too earlier! By the way I love this weather!

[donsutherland1]

The afternoon saw plentiful sunshine, fluffy cumulus clouds, and readings in the 70s. The New York Botanical Garden is transitioning to more of an autumn appearance.

[lee59]

With the earlier sunset the temperatures fall pretty far pretty fast. After a 73 degree high, it is already down 10 degrees to 63.

[donsutherland1]

Tomorrow will be mostly sunny and unseasonably warm. Temperatures will likely reach the upper 70s and lower 80s. Tuesday will also be warm, but a cold front will push across the region overnight bringing some showers and perhaps thundershowers to parts of the region. Afterward, the coolest air so far this fall will close out the month.

The MJO had recently been locked in Phase 3 at a high amplitude, frequently in excess of 1.500. Only 2006 and 2009 saw the MJO in Phase 3 at an amplitude of 1.500 or above for 2 or more days during September 10-20. Both years saw September end with a cold shot that continued into the first days of October. Both days saw Central Park's temperature fall to 49° on September 30. The guidance has now come into better agreement concerning a cool shot to end the month. Afterward, in the MJO cases, a fairly sharp rebound in temperatures followed. October wound up wetter than normal with 7.07" rainfall in 2006 and 5.58" of rainfall in 2009. Normal rainfall (1991-2020) is 4.38".

2021 remains on course to become the 6th out of the last 7 years during which September has had a mean temperature of 70° or above in New York City. Prior to 2000, New York City saw such warmth on average once every five years. In short, September has become more an extension of summer than a gateway to autumn in the New York City area.

There is increasing consensus on the long-range guidance that October will be an unseasonably warm month. The first half could feature much above normal readings in the Northern Plains into Central Canada.

Fall 2021 will likely be wetter to much wetter than normal in the northern Middle Atlantic region. Since 1869, there have been 9 August cases where New York City picked up 20.00" or more rainfall during the summer. Two thirds of those cases (and 4/5 of those with summer mean temperatures of 73.0° or above) had 17.00" or more fall precipitation in New York City. 2011 is probably the closest match in terms of precipitation and a nearly identical summer mean temperature. Mean fall precipitation for those 9 cases was 14.86". The median was 17.35". The 1991-2020 normal value is 12.27".

The ENSO Region 1+2 anomaly was +0.2°C and the Region 3.4 anomaly was -0.4°C for the week centered around September 15. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.03°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral ENSO conditions will likely prevail through September. Afterward, La Niña conditions could begin to develop.

The SOI was -0.24 today.

The preliminary Arctic Oscillation (AO) figure was -0.455 today.

On September 24 the MJO was in Phase 4 at an amplitude of 0.714 (RMM). The September 23-adjusted amplitude was 0.945 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 94% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 70.4° (1.2° above normal).

 

[lee59]

If it stays clear all night and tomorrows mild air doesn't start infiltrating tonight, this could be my chilliest night of the early fall season. Down to 58 degrees already.

[lee59]

22 hours ago, donsutherland1 said:

Under partly sunny skies with temperatures in the 70s, it was another fine late September beach day.

 

I went up to the top of the lighthouse today. First time, great view and very windy.

[donsutherland1]

14 minutes ago, lee59 said:

I went up to the top of the lighthouse today. First time, great view and very windy.

It’s usually quite breezy up there. The views have been great the past few days with the absence of haze.

[lee59]

Just now, donsutherland1 said:

It’s usually quite breezy up there. The views have been great the past few days with the absence of haze.

Yea it was a beautiful day as far as visibility. The NW wind was about 15-30 mph. 

[Sanman 06]

4 hours ago, RippleEffect said:

I don’t get it I saw one too earlier! By the way I love this weather!

I work for DSNY we go out on trial runs before winter to make sure gps we use for snow routes works probably and that all routes flow smoothly..  LET IT SNOW !!! ❄️☃️

[LibertyBell]

On 9/25/2021 at 6:26 PM, lee59 said:

It seems in my area this season, we get very heavy rain over a 24 hour period and then very little or nothing for the next 2-3 weeks.

I'm perfectly fine with that.  Rain gets boring and dismal and dreary.  I love this low humidity weather, I am fine with 70s by day and 50s by night through the end of October!