September 2021

[bluewave]

21 minutes ago, uncle W said:

What...I said it...these are three or more days with a max 80 or above for three days or longer starting around the first day of calendar fall...two of my favorite winters from my youth 1959-60 and 1968-69 had late heat...

2017 and 1959 were the only two heatwaves I could find at Newark after 9-20.

9-23-17….90°

9-24-17….92°

9-25-17….92°

9-22-59….90°

9-23-59….93°

9-24-59….92°

[forkyfork]

54 minutes ago, bluewave said:

Endless summer in September doesn’t mean every day for the rest of the month hits 90° at a place like Newark. Plenty of 80°+ days with the potential for several 90s mixed in. So an extended period when most of the days are above average. 
 

Newark daily average high and low

9-13…..79/62

9-20…..76/59

9-27…..73/56

probably high dewpoints/minimums driving the positive departures

[uncle W]

5 minutes ago, bluewave said:

2017 and 1959 were the only two heatwaves I could find at Newark after 9-20.

9-23-17….90°

9-24-17….92°

9-25-17….92°

9-22-59….90°

9-23-59….93°

9-24-59….92°

1970 just missed with three out of four...five straight 88 or higher...

[LibertyBell]

2 hours ago, bluewave said:

2017 and 1959 were the only two heatwaves I could find at Newark after 9-20.

9-23-17….90°

9-24-17….92°

9-25-17….92°

9-22-59….90°

9-23-59….93°

9-24-59….92°

Did we have that in 1983?  No one has given me an explanation of how in the world JFK had 5 days of 90+ in September in 1983 when I could not find another September with more than 2.  And the entire summer had been hot too.  How does 1983 not come up more often as one of the hottest summers of all time?

 

[LibertyBell]

2 hours ago, forkyfork said:

probably high dewpoints/minimums driving the positive departures

I need to find a wall to punch

[LibertyBell]

2 hours ago, uncle W said:

1970 just missed with three out of four...five straight 88 or higher...

1983 has to be on this list, it was the Nolan Ryan of summers, it's longevity was simply outstanding.

 

[LibertyBell]

3 hours ago, bluewave said:

Endless summer in September doesn’t mean every day for the rest of the month hits 90° at a place like Newark. Plenty of 80°+ days with the potential for several 90s mixed in. So an extended period when most of the days are above average. 
 

Newark daily average high and low

9-13…..79/62

9-20…..76/59

9-27…..73/56

Yeah but I meant that as a general statement how come we don't get 7+ day heatwaves anymore?  Even in our intense bouts of heat I notice they dont last more than 5 days at most.  I think July 1993 was the last time we had a string of 7+ 90 degree days? Or maybe it was July 1999.

 

[uncle W]

10 minutes ago, LibertyBell said:

1983 has to be on this list, it was the Nolan Ryan of summers, it's longevity was simply outstanding.

 

you don't have to ask...all that is at your finger tips...

they had one from the 18th-21st...it started a few days to soon... not make the cut...

IPS-9C06A686-6E3A-43BE-81C4-1A03C8E08817.pdf (noaa.gov)

[donsutherland1]

Much of the region saw cloudy, cool, and sometimes rainy conditions today. With 0.26" of rain, New York City has now picked up 49.44" of rain this year. As a result, there is an implied 86% probability that NYC will see 60" or more precipitation this year for just the 9th time on record. All 8 prior cases have occurred after 1970 and 3 have occurred since 2000. Records go back to 1869.

Out West, record heat prevailed in a number of locations. At Phoenix, the temperature soared to 111°. That broke the daily record of 110° that was set in 1974 and tied in 1990. At Boise, the high temperature of 98° smashed the previous record of 95°, which had been set in 1997. At Denver, the temperature rose to 96°, which broke the daily record of 94°. The old record was set in 1931 and tied in 1998 and 1994.

Tomorrow will be another very hot day in Denver. The NBE shows a high temperature of 98° with a standard deviation of 2°. That means there is an implied 16% probability that the temperature could reach 100°. The latest 100° reading there was set on September 5, 2020 when the mercury reached 101°. The prior record was 100° on September 2, 2019.

A warming trend will likely develop this weekend. Sunday could be unseasonably warm with temperatures rising into the upper 80s as far north as New York City. Despite a cooler than normal first 7-10 days, September will likely feature near normal to somewhat warmer than normal temperatures in much of the region. The second half of the month could feature above to perhaps much above normal temperatures. As a result, 2021 is increasingly likely 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.

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 -0.3°C for the week centered around September 1. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.22°C and the ENSO Region 3.4 anomaly has averaged -0.43°C. Neutral ENSO conditions will likely prevail through September. Afterward, La Niña conditions could begin to develop.

The SOI was +7.67 today.

The preliminary Arctic Oscillation (AO) figure was -0.538 today.

On September 7 the MJO was in Phase 4 at an amplitude of 1.306 (RMM). The September 6-adjusted amplitude was 1.100 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 68% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 70.3° (1.1° above normal).

 

[LibertyBell]

2 minutes ago, uncle W said:

you don't have to ask...all that is at your finger tips...

they had one from the 18th-21st...it started a few days to soon... not make the cut...

IPS-9C06A686-6E3A-43BE-81C4-1A03C8E08817.pdf (noaa.gov)

Oh wow was that September the latest record of a 95+ temp? I know they almost hit 100 on 9/11/83, that had to be the latest it ever hit 99, no?

 

[LibertyBell]

1 minute ago, donsutherland1 said:

Much of the region saw cloudy, cool, and sometimes rainy conditions today. With 0.26" of rain, New York City has now picked up 49.44" of rain this year. As a result, there is an implied 86% probability that NYC will see 60" or more precipitation this year for just the 9th time on record. All 8 prior cases have occurred after 1970 and 3 have occurred since 2000. Records go back to 1869.

Out West, record heat prevailed in a number of locations. At Phoenix, the temperature soared to 111°. That broke the daily record of 110° that was set in 1974 and tied in 1990. At Boise, the high temperature of 98° smashed the previous record of 95°, which had been set in 1997. At Denver, the temperature rose to 96°, which broke the daily record of 94°. The old record was set in 1931 and tied in 1998 and 1994.

Tomorrow will be another very hot day in Denver. The NBE shows a high temperature of 98° with a standard deviation of 2°. That means there is an implied 16% probability that the temperature could reach 100°. The latest 100° reading there was set on September 5, 2020 when the mercury reached 101°. The prior record was 100° on September 2, 2019.

A warming trend will likely develop this weekend. Sunday could be unseasonably warm with temperatures rising into the upper 80s as far north as New York City. Despite a cooler than normal first 7-10 days, September will likely feature near normal to somewhat warmer than normal temperatures in much of the region. The second half of the month could feature above to perhaps much above normal temperatures. As a result, 2021 is increasingly likely 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.

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 -0.3°C for the week centered around September 1. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.22°C and the ENSO Region 3.4 anomaly has averaged -0.43°C. Neutral ENSO conditions will likely prevail through September. Afterward, La Niña conditions could begin to develop.

The SOI was +7.67 today.

The preliminary Arctic Oscillation (AO) figure was -0.538 today.

On September 7 the MJO was in Phase 4 at an amplitude of 1.306 (RMM). The September 6-adjusted amplitude was 1.100 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 68% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 70.3° (1.1° above normal).

 

Don didn't Denver have a snowfall a few days after it hit 100 there back in September 2020? I remember that.....

Also did either they or Boise set their new record for most 100 degree days in a season this year?

 

[uncle W]

17 minutes ago, LibertyBell said:

Did we have that in 1983?  No one has given me an explanation of how in the world JFK had 5 days of 90+ in September in 1983 when I could not find another September with more than 2.  And the entire summer had been hot too.  How does 1983 not come up more often as one of the hottest summers of all time?

 

xmACIS2 (rcc-acis.org)

[uncle W]

6 minutes ago, LibertyBell said:

Oh wow was that September the latest record of a 95+ temp? I know they almost hit 100 on 9/11/83, that had to be the latest it ever hit 99, no?

 

JFK highest temps...

9/1	92 in 2012	92 in 2010	91 in 1969+
9/2	93 in 1973	93 in 1961	93 in 1953
9/3	93 in 2015	93 in 1993	92 in 1957
9/4	93 in 2018	93 in 1985	92 in 1961
9/5	94 in 1961	92 in 1985	92 in 1964
9/6	92 in 1985	90 in 1998	90 in 1983+
9/7	93 in 1983	92 in 1978	89 in 1998
9/8	92 in 2010	91 in 2015	87 in 2013+
9/9	93 in 1959	91 in 2016	88 in 1964
9/10	98 in 1983	92 in 1989	90 in 1961
9/11	96 in 1983	91 in 1989	89 in 1961
9/12	91 in 1981	90 in 2005	90 in 1952
9/13	94 in 1952	89 in 1994	89 in 1957
9/14	89 in 1995	89 in 1972	88 in 1981+
9/15	85 in 2008	82 in 2009	82 in 1997+
9/16	89 in 1991	88 in 1998	88 in 1970
9/17	90 in 1991	84 in 2015	84 in 1969
9/18	90 in 1965	86 in 1964	86 in 1948
9/19	90 in 1983	85 in 1985	85 in 1963
9/20	85 in 1997	85 in 1983	83 in 1955
9/21	85 in 2016	83 in 2004	83 in 1989
9/22	91 in 1980	87 in 1961	86 in 1970
9/23	90 in 1970	89 in 1961	88 in 2017+
9/24	92 in 2017	88 in 1970	86 in 1961
9/25	87 in 2010	85 in 2017	83 in 2011
9/26	87 in 1970	85 in 1958	82 in 1968
9/27	89 in 1998	87 in 2017	84 in 2014+
9/28	82 in 1948	81 in 1961	81 in 1959+
9/29	82 in 1948	81 in 2019	81 in 1959
9/30	84 in 1986	82 in 1959	80 in 1971+
10/1	85 in 1986	84 in 1954	84 in 1950
10/2	95 in 2019	85 in 2013	82 in 2002+
10/3	84 in 2002	82 in 2000	81 in 1969
10/4	84 in 1967	83 in 1959	83 in 1954
10/5	84 in 1967	83 in 2017	83 in 2002+
10/6	88 in 1997	85 in 1995	83 in 1959
10/7	83 in 2007	83 in 1961	82 in 1997
10/8	90 in 2007	78 in 1959	76 in 2011
10/9	87 in 2011	82 in 1961	82 in 1959
10/10	86 in 1997	84 in 2017	84 in 2011

[donsutherland1]

15 minutes ago, LibertyBell said:

Don didn't Denver have a snowfall a few days after it hit 100 there back in September 2020? I remember that.....

Also did either they or Boise set their new record for most 100 degree days in a season this year?

 

Boise is 2nd and Denver is 3rd. Bismarck, Fresno, and Seattle set new records for 100 degree days. Portland (OR) and Salt Lake City tied the record for 100 degree days.

[LibertyBell]

1 minute ago, donsutherland1 said:

Boise is 2nd and Denver is 3rd. Bismarck, Fresno, and Seattle set new records for 100 degree days. Portland (OR) and Salt Lake City tied the record for 100 degree days.

is Boise really close to first though? I know they were just a couple days away from it

[LibertyBell]

13 minutes ago, uncle W said:

JFK highest temps...

9/1	92 in 2012	92 in 2010	91 in 1969+
9/2	93 in 1973	93 in 1961	93 in 1953
9/3	93 in 2015	93 in 1993	92 in 1957
9/4	93 in 2018	93 in 1985	92 in 1961
9/5	94 in 1961	92 in 1985	92 in 1964
9/6	92 in 1985	90 in 1998	90 in 1983+
9/7	93 in 1983	92 in 1978	89 in 1998
9/8	92 in 2010	91 in 2015	87 in 2013+
9/9	93 in 1959	91 in 2016	88 in 1964
9/10	98 in 1983	92 in 1989	90 in 1961
9/11	96 in 1983	91 in 1989	89 in 1961
9/12	91 in 1981	90 in 2005	90 in 1952
9/13	94 in 1952	89 in 1994	89 in 1957
9/14	89 in 1995	89 in 1972	88 in 1981+
9/15	85 in 2008	82 in 2009	82 in 1997+
9/16	89 in 1991	88 in 1998	88 in 1970
9/17	90 in 1991	84 in 2015	84 in 1969
9/18	90 in 1965	86 in 1964	86 in 1948
9/19	90 in 1983	85 in 1985	85 in 1963
9/20	85 in 1997	85 in 1983	83 in 1955
9/21	85 in 2016	83 in 2004	83 in 1989
9/22	91 in 1980	87 in 1961	86 in 1970
9/23	90 in 1970	89 in 1961	88 in 2017+
9/24	92 in 2017	88 in 1970	86 in 1961
9/25	87 in 2010	85 in 2017	83 in 2011
9/26	87 in 1970	85 in 1958	82 in 1968
9/27	89 in 1998	87 in 2017	84 in 2014+
9/28	82 in 1948	81 in 1961	81 in 1959+
9/29	82 in 1948	81 in 2019	81 in 1959
9/30	84 in 1986	82 in 1959	80 in 1971+
10/1	85 in 1986	84 in 1954	84 in 1950
10/2	95 in 2019	85 in 2013	82 in 2002+
10/3	84 in 2002	82 in 2000	81 in 1969
10/4	84 in 1967	83 in 1959	83 in 1954
10/5	84 in 1967	83 in 2017	83 in 2002+
10/6	88 in 1997	85 in 1995	83 in 1959
10/7	83 in 2007	83 in 1961	82 in 1997
10/8	90 in 2007	78 in 1959	76 in 2011
10/9	87 in 2011	82 in 1961	82 in 1959
10/10	86 in 1997	84 in 2017	84 in 2011

wow October 2019 blows everything else away for latest 90+

But 1983 hit 98 there in September 1983

[donsutherland1]

18 minutes ago, LibertyBell said:

is Boise really close to first though? I know they were just a couple days away from it

Boise has 18 days. The record is 20 days. That record was set in 2003.

[Rtd208]

Picked up 0.44" of rain for the day yesterday. 

Current temp 61/DP 57/RH 88%

[CIK62]

The next 8 days are averaging 75degs.(68/82), or +5.

Month to date is  71.3[-1.4].       Could be  73.0[+1.6] by the 18th.

75 to 78 today, breezy from nw, few clouds.

65*(80%RH) here at 6am, m. clear.   64* at 7am.       69* by Noon.         Reached 76* at 5:30pm.

[SACRUS]

Clearing out and looking dry through Thursday (9/15).  Just terrific weather today and tomorrow highs near 80 and low humidity.  By Sun (9/12) through much of the next work wek warmer times coincide with ridging along the east coast and what played very similarly as the late july cool down / near or below normal week transitioning to a another sustained warm period is likely happening here for the next few weeks.  Mon (9/13) - Wed (9/15) warm spots with 90s possible or likely as 850 temps get >16c.  Some storms/showers Thu (9/16) and late next week may limit warmth before the ridge builds back next weekend 9/17 - 18 and beyond with overall warmer than normal into the second half/late month.

[donsutherland1]

Morning thoughts…

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

New York City (Central Park): 76°

Newark: 79°

Philadelphia: 77°

Normals:

New York City: 30-Year: 78.4°; 15-Year: 78.8°

Newark: 30-Year: 79.8°; 15-Year: 80.3°

Philadelphia: 30-Year: 81.0°; 15-Year: 81.3°

Sunday and Monday will be very warm days.

Out West, Denver will likely smash its daily record high temperature of 93°, which was set in 1931 and tied in 1974, 1994, 1998, and 2018. There is an implied 16% probability that Denver could reach 100°. If so, that would be the latest such temperature on record. The record was set just last year on September 5. Prior to that, the record was September 2, 2019. Prior to the 2010s, the record was set on August 16, 2002. Prior to the 2000s, the record was set on August 14, 1962.

[rclab]

1 hour ago, donsutherland1 said:

Morning thoughts…

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

New York City (Central Park): 76°

Newark: 79°

Philadelphia: 77°

Normals:

New York City: 30-Year: 78.4°; 15-Year: 78.8°

Newark: 30-Year: 79.8°; 15-Year: 80.3°

Philadelphia: 30-Year: 81.0°; 15-Year: 81.3°

Sunday and Monday will be very warm days.

Out West, Denver will likely smash its daily record high temperature of 93°, which was set in 1931 and tied in 1974, 1994, 1998, and 2018. There is an implied 16% probability that Denver could reach 100°. If so, that would be the latest such temperature on record. The record was set just last year on September 5. Prior to that, the record was September 2, 2019. Prior to the 2010s, the record was set on August 16, 2002. Prior to the 2000s, the record was set on August 14, 1962.

Good morning Don and quite sobering. The next best seller at Penn State may possibly be ‘the statistics of atmospheric extremes’. As always ….

[MJO812]

[bluewave]

It’s no surprise that September and October have the fastest rising fall temperatures around the region. The figures below are the increase in monthly average temperatures for the new 30 year climate normals from 1981-2010 to 1991-2020. The slower rising November temperatures explain how we were able to get record November snows in recent years.

EWR

Sep….+1.0

Oct...+0.9

Nov…+0.2

NYC

+1.2

+1.0

+0.3

LGA

+1.7

+1.5

+0.8

JFK

+0.3

+0.2

-0.7

ISP

+1.3

+1.4

+0.5

HPN

+1.6

+1.6

+0.5

 

 

[donsutherland1]

1 hour ago, rclab said:

Good morning Don and quite sobering. The next best seller at Penn State may possibly be ‘the statistics of atmospheric extremes’. As always ….

And frequent revisions will very likely be needed.

[forkyfork]

4 hours ago, bluewave said:

It’s no surprise that September and October have the fastest rising fall temperatures around the region. The figures below are the increase in monthly average temperatures for the new 30 year climate normals from 1981-2010 to 1991-2020. The slower rising November temperatures explain how we were able to get record November snows in recent years.

true west of us as well

 

[LibertyBell]

8 hours ago, SACRUS said:

Clearing out and looking dry through Thursday (9/15).  Just terrific weather today and tomorrow highs near 80 and low humidity.  By Sun (9/12) through much of the next work wek warmer times coincide with ridging along the east coast and what played very similarly as the late july cool down / near or below normal week transitioning to a another sustained warm period is likely happening here for the next few weeks.  Mon (9/13) - Wed (9/15) warm spots with 90s possible or likely as 850 temps get >16c.  Some storms/showers Thu (9/16) and late next week may limit warmth before the ridge builds back next weekend 9/17 - 18 and beyond with overall warmer than normal into the second half/late month.

for some odd reason Lee Goldberg just made a sort of prediction 7 days out that next Friday a tropical system may be along the east coast and be bringing us rain.  Really shocked that he would do that a week out.

[LibertyBell]

6 hours ago, bluewave said:

It’s no surprise that September and October have the fastest rising fall temperatures around the region. The figures below are the increase in monthly average temperatures for the new 30 year climate normals from 1981-2010 to 1991-2020. The slower rising November temperatures explain how we were able to get record November snows in recent years.

EWR

Sep….+1.0

Oct...+0.9

Nov…+0.2

NYC

+1.2

+1.0

+0.3

LGA

+1.7

+1.5

+0.8

JFK

+0.3

+0.2

-0.7

ISP

+1.3

+1.4

+0.5

HPN

+1.6

+1.6

+0.5

 

 

Surprised it's September and October, I thought it would be December with how warm recent Decembers have been.

 

[LibertyBell]

2 hours ago, forkyfork said:

true west of us as well

 

What they have to point out is September actually IS summer- most of it anyway.  Fall doesn't start until after three weeks of September.

 

[donsutherland1]

FYI, the smoke will be returning.