September 2019 General Discussions & Observations Thread

[dWave]

A hint of humidity this morning compared to previous days, sunny 66/60

[SACRUS]

2 hours ago, SnoSki14 said:

Serious short term drought could develop based on guidance showing little to no rain next 2 weeks and very warm temperatures. 

Grass is already getting very brown.

The real, sustained ridge won't develop until Thu/Fri of this week. It may also cause TS Karen to impact the US as Euro shows. 

You wonder if Karen eventual becomes the dry breaker and next deluge towards Oct 5th. Way out there.  

[SACRUS]

Late Sep heat records may be in trouble next weekend 28th, 29th  and perhaps to open October.  But first lets check out late Sep records

LGA:
9/23 93 (1970)
9/24 91 (2017)
9/25 90 (2010*)
9/26 90 (2007)
9/27 90 (1988)
9/28 84 (2014*)
9/29 86 (1945)
9/30 88 (1986)

EWR:

9/23  94 (1970)    
9/24  92 (2017)    
9/25  91 (1970)     
9/26  90 (2007)     
9/27  91 (1998)     
9/28  87 (2014)    
9/29  89 (1945)    
9/30  89 (1986)    

 

[Rtd208]

2 hours ago, bluewave said:

0z Euro and GFS have near record heat potential moving up the East Coast next weekend. One of the strongest SE Ridges that we have seen this time of year. They also have an expansion of drought conditions with very little rain. So keep watering your gardens. 

Newark record highs for next weekend

9/28	87 in 2014	85 in 1954	85 in 1943
9/29	89 in 1945	83 in 1959	82 in 2015+
9/30	89 in 1986	85 in 1954	82 in 1960+

 

Potential low to mid 90's for the NYC metro?

[dWave]

Definitely a more summer feel today. 

Not that often I see a forecast for such wall to wall sunshine for a week around here.

[SACRUS]

ECM surges 850’s to 16-19c next weekend and again by Tuesday oct 2nd.  We’ll need to see if it is blunted west and south towards the DC area again as well as any tropical impacts on the flow.  As bluewave noted,  ridging looks glued to and along the east coast overall into October.

[MJO812]

Next threat to watch for the SE coast is 99L

[Brian5671]

Euro weeklies are at dry torch into early November 

[dmillz25]

Up to 87 here

[JustinRP37]

87 with a 63 dew point. Lots of dry leaves around and grass is definitely browning now. 

[doncat]

87° high today.

[NYCweatherNOW]

Perfect weather can’t get a better weekend than this. 85 currently 

[Rtd208]

Current temp is 88 here.

[donsutherland1]

The last full day of summer featured lots of sunshine and summerlike warmth. As of 3 pm, New York City had a high temperature of 86° and Newark had registered a high temperature of 88°. On the Long Island Sound, a refreshing sea breeze kicked in during the middle of the afternoon.

Three photos from this afternoon:

[CIK62]

South wind (10-15mph) prevented theoretical high from being reached while I was on the beach here, 1pm-4pm.     A large 'weekday like crowd', for this post season weekend.    I believe this same 'end of summer weekend' just two years ago, was 91*.

 

[winterwarlock]

Hit 91 today..wow

[purduewx80]

6 hours ago, SACRUS said:

ECM surges 850’s to 16-19c next weekend and again by Tuesday oct 2nd.  We’ll need to see if it is blunted west and south towards the DC area again as well as any tropical impacts on the flow.  As bluewave noted,  ridging looks glued to and along the east coast overall into October.

pretty incredible heat wave showing up on 12Z guidance, but there are timing differences between the op runs and their ensembles. the spread is anywhere from sept 29 thru oct 4, with peak temps in the mid-90s suggested at the usual hot spots. how far east and north the heat makes it will depend on the surface high being centered to the south of one's location, allowing for some form of westerly flow. as we've seen recently, high heights do not translate to heat if easterly flow prevails.

the apparent lack of rain between then and now, already dry soils and surface temps exceeding guidance the past few days suggest the potential is there for historic heat across a large portion of the mid-atlantic and perhaps parts of the northeast near the beginning of the new month. overwhelming ensemble and model support leads to higher than normal confidence for a hot outcome at this range. still, plenty could change between now and then.

[Fantom X]

3 minutes ago, purduewx80 said:

pretty incredible heat wave showing up on 12Z guidance, but there are timing differences between the op runs and their ensembles. the spread is anywhere from sept 29 thru oct 4, with peak temps in the mid-90s suggested at the usual hot spots. how far east and north the heat makes it will depend on the surface high being centered to the south of one's location, allowing for some form of westerly flow. as we've seen recently, high heights do not translate to heat if easterly flow prevails.

the apparent lack of rain between then and now, already dry soils and surface temps exceeding guidance the past few days suggest the potential is there for historic heat across a large portion of the mid-atlantic and perhaps parts of the northeast near the beginning of the new month. overwhelming ensemble and model support leads to higher than normal confidence for a hot outcome at this range. still, plenty could change between now and then.

It is extremely dry down here. all of the trees leaves are yellowing, drying up and dropping to the ground. Most of the grass along the highways are brown.  26th day in a row here without a drop of rain. 

Looking forward to visiting Long Island between 9/29 and 10/5 & getting a wiff of that sea breeze again

 

[bluewave]

+15 high temperature departure at Newark today.

MAXIMUM         89    200 PM  94    1970  74     15    

https://forecast.weather.gov/product.php?site=NWS&issuedby=EWR&product=CLI&format=CI&version=1&glossary=1&highlight=off

[dWave]

High 87 here. Rapid warm up until the south wind kept temp steady, now down to 80/66.

NY Mesonet highs

 

[JerseyWx]

1 hour ago, purduewx80 said:

pretty incredible heat wave showing up on 12Z guidance, but there are timing differences between the op runs and their ensembles. the spread is anywhere from sept 29 thru oct 4, with peak temps in the mid-90s suggested at the usual hot spots. how far east and north the heat makes it will depend on the surface high being centered to the south of one's location, allowing for some form of westerly flow. as we've seen recently, high heights do not translate to heat if easterly flow prevails.

the apparent lack of rain between then and now, already dry soils and surface temps exceeding guidance the past few days suggest the potential is there for historic heat across a large portion of the mid-atlantic and perhaps parts of the northeast near the beginning of the new month. overwhelming ensemble and model support leads to higher than normal confidence for a hot outcome at this range. still, plenty could change between now and then.

Pretty amazing honestly.  I wonder if this Fall will rival 2015 (in terms of average).  Of course December was way AN that year.

[NYCweatherNOW]

No sign of 90’s for Central Park for the rest of the month. Yes big time heat but no 90’s and around October 6th looks like the cold weather actually rolls in

[donsutherland1]

Today saw temperatures rise into the middle and upper 80s across the Middle Atlantic region. A few locations reached or exceeded 90°. High temperatures included: Allentown: 90°; Baltimore: 91°; Harrisburg: 91°; New York City: 86°; Newark: 89°; Philadelphia: 89°; Richmond: 92°; Sterling: 91°; and, Washington, DC: 93°. Parts of southern New England also saw readings well into the 80s, including Boston (89°), Hartford (88°), and Providence (85°).

Today was the 56th time Baltimore recorded a 90° or above high temperature. Only 2010, with 59, had more. Today was Washington, DC's 58th 90° or warmer day this year, which tied 2016 for the 8th most such days during a year.

Courtesy of low sea ice, abnormal warmth continued to prevail in northern Alaska. There is an implied 89% probability that Utqiagvik (formerly Barrow) will record its warmest September on record. It is possible that Utqiagvik could register its first 40° mean temperature for September. A 40.0° mean temperature would rank 30th out of 99 years for the warmest August on record). The existing monthly record of 37.7° has stood since 1998.

The ENSO Region 1+2 anomaly was -1.3°C and the Region 3.4 anomaly was -0.3°C for the week centered around September 11. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.65°C and the ENSO Region 3.4 anomaly has averaged -0.03°C. There remains uncertainty about the ENSO evolution later this fall. Despite the guidance, the strong cooling in Region 1+2 indicates that the prospects for a neutral-cool ENSO during the winter have increased. Such a scenario may be somewhat more likely than not. That outcome could have significant winter season implications.

Since 1991 when weekly ENSO region data was available, six years have seen September record 2 or more weeks with -1.0°C or cooler weekly anomalies in Region 1+2: 1996, 1999, 2002, 2007, 2010, and 2017. 5/6 (83%) of those cases went on to feature warm December-February temperature anomalies in the Middle Atlantic and southern New England regions. 2002 had one such week ahead of what would evolve into an El Niño winter.

The SOI was -11.94 today.

On September 19, the SOI fell to -35.30. Often an SOI figure at or below -30.00 during the second half of September has been followed by a warmer than normal October. 2002, which saw severe October blocking during which the Arctic Oscillation fell to as low as -5.098 on October 18, was an exception.

Today, the preliminary Arctic Oscillation (AO) figure was +0.676.

Since 1950, there have been five prior cases when the AO averaged -0.500 or below in both July and August: 1950, 1958, 1960, 1968, and 2015. The average temperature for September was 69.1° (69.8° after adjusting for ongoing warming) and 58.9° (59.6° adjusted) for September through November in New York City. The 1981-2010 baseline normal figures are 68.0° and 57.5° respectively. The majority of cases saw a warmer than normal September and all cases featured a warmer than normal fall.

Among those five cases, 2015 made a transition from predominantly negative AO values to predominantly positive ones during the fall. The combination of the AO's recent increase to the strongest positive values since April and some of the extended range guidance leave open a scenario where the AO is currently in the early stages of evolving to a predominantly positive regime. Such an outcome would also favor a warmer than normal fall and possible warm start to winter in the Middle Atlantic and southern New England regions. For now, this is merely a hypothetical discussion of one potential path toward winter. Many other variables are involved. The only idea that carries weight at this time is that the possible evolution reaffirms the longstanding signal for a warm fall.

Therefore, a warmer than normal September and fall appear likely. The potential for autumn 2019 to rank among the 30 warmest cases on record remains on the table. For New York City, that would translate into a September-November mean temperature of 58.8°.

On September 21, the MJO was in Phase 1 at an amplitude of 1.466 (RMM). The September 20-adjusted amplitude was 1.377.

Based on sensitivity analysis applied to the latest guidance, the implied probability of New York City having a warmer than normal September is approximately 92% and the probability of a monthly mean temperature of 70.0° or above is 61%. Should September 2019 have a mean temperature of 70.0° or above, 2019 would be the 5th consecutive year with such September warmth. Prior to the current stretch, the record was 2 consecutive years (1930 and 1931; 1970 and 1971; 1979 and 1980; and, 2010 and 2011).

[SACRUS]

9/22

TEB: 92
EWR: 89
New Bnswk: 89
PHL: 89
TTN: 87
NYC: 86
LGA: 86
ACY: 85
BLM: 84
ISP: 81
JFK: 80

[JerseyWx]

5 hours ago, bluewave said:

It will be interesting to see if we can add another 60+ degree  fall  this decade. It has pretty much become the new normal.

Time Series Summary for LA GUARDIA AP, NY
Click column heading to sort ascending, click again to sort descending.

Rank	Year	Mean Avg Temperature	Missing Count
1	2016	62.5	0
2	2015	61.9	0
-	2007	61.9	0
-	2005	61.9	0
3	2017	61.7	0
4	1990	61.0	0
5	1946	60.9	0
6	2001	60.8	0
7	2010	60.7	0
8	1941	60.6	0
9	2006	60.5	0
-	1961	60.5	0
10	2011	60.4	0
-	1953	60.4	0
11	1985	60.3	0

Time Series Summary for NEWARK LIBERTY INTL AP, NJ
Click column heading to sort ascending, click again to sort descending.

Rank	Year	Mean Avg Temperature	Missing Count
1	2015	60.9	0
2	1971	60.4	0
-	1961	60.4	0
3	2017	60.3	0
-	1990	60.3	0
4	2016	60.1	0
-	2011	60.1	0
-	1994	60.1	0
5	2005	60.0	0
-	1973	60.0	0

 

 

 

Since 2015 we've experienced warmth with incredible staying power.  Last Summer was a prime example.

[CIK62]

Next 8 days are averaging just 70degs. or about 6degs. AN.

Month to date is  +0.6[70.1].          September should end near +2.0[70.0].

70.5* here at 6am.   71.0* by 8am.    77.0* by Noon.

Really no BN day, except by accident, till Oct. 05.

[NYCweatherNOW]

If the GfS is right today is the real last day of heat, and I believe it’s wrong for many reasons being inconsistent reasoning number one. It’s always flopping back and forth! Euro and Canadian still have some good heat for next week.

[MJO812]

Happy 1st day of Autumn

[bluewave]

Today could be the first time since 2010 that fall started with a 90 degree day at Newark.

Newark first day of fall high temperatures since 2010

9-22-10...90

9-23-11...75

9-22-12...78

9-22-13...72

9-22-14....73

9-23-15....80

9-22-16....84

9-22-17....85

9-22-18....75

 

 

 

[psv88]

Toasty low of 69 last night. Today will be uncomfortable