May 2021

[LibertyBell]

4 hours ago, bluewave said:

The 36° degree difference between the high and low at JFK is the 2nd greatest on record for May. Just goes to show how dry it has been. This is closer to normal for Tucson, Arizona.

 

CLIMATE REPORT 
NATIONAL WEATHER SERVICE NEW YORK, NY
434 PM EDT SAT MAY 22 2021

...................................

...THE KENNEDY NY CLIMATE SUMMARY FOR MAY 22 2021...
VALID TODAY AS OF 0400 PM LOCAL TIME.

CLIMATE NORMAL PERIOD 1991 TO 2020
CLIMATE RECORD PERIOD 1948 TO 2021


WEATHER ITEM   OBSERVED TIME   RECORD YEAR NORMAL DEPARTURE LAST      
                VALUE   (LST)  VALUE       VALUE  FROM      YEAR     
                                                  NORMAL           
...................................................................
TEMPERATURE (F)                                                          
 TODAY                                                               
  MAXIMUM         94R   148 PM  94    1992  70     24       73       
  MINIMUM         58    243 AM  43    1990  54      4       52       
  AVERAGE         76                        62     14       63    

 

...THE TUCSON AZ CLIMATE SUMMARY FOR MAY 21 2021...

CLIMATE NORMAL PERIOD 1991 TO 2020
CLIMATE RECORD PERIOD 1895 TO 2021


WEATHER ITEM   OBSERVED TIME   RECORD YEAR NORMAL DEPARTURE LAST      
                VALUE   (LST)  VALUE       VALUE  FROM      YEAR     
                                                  NORMAL           
...................................................................
TEMPERATURE (F)                                                          
 YESTERDAY                                                           
  MAXIMUM         89    325 PM 107    2005  94     -5       89       
  MINIMUM         68   1159 PM  42    1899  63      5       53       
  AVERAGE         79                        78      1       71     

at this rate this could be like 1966 and JFK could go above 100 multiple times in the summer

 

[LibertyBell]

6 hours ago, Rjay said:

 

Bring on the rain please.   Thanks.  My garden and lawn need it.  

yeah I dont need it dry again until July when we'll hopefully be hitting 100+ on Long Island

 

[LibertyBell]

6 hours ago, Rjay said:

Lol Central Park. 

it's funny LGA only got to 88 too, meanwhile JFK rocked out at 94 lol,  I could use this kind of weather all summer.  

Hopefully JFK will hit 104 in the summer and I can say I got to experience what 40 C feels like

 

[LibertyBell]

5 hours ago, donsutherland1 said:

The temperature rose into the upper 80s and lower 90s across much of the region today. 90° or above temperatures were reported at:

Atlantic City: 94° (old record: 91°, 1992)
Baltimore: 93°
Georgetown, DE: 93° (old record: 92°, 1996)
Hartford: 90°
Islip: 90°
New York City-JFK: 94° (tied record set in 1992)
Newark: 96°
Philadelphia: 92°
Washington, DC: 91°
Wilmington, DE: 92°

The high temperature at Central Park was 89°. Today was the first day on record in May where Central Park had a temperature below 90° while Islip had a high temperature of 90° or above. It was also the first day on record where Central Park had a high temperature below 90° and both Islip and JFK Airport saw 90° or above high temperatures. Prior to today, there were two cases in May where JFK Airport had a high temperature of 90° or above while Central Park did not reach 90°:

May 13, 1956: JFK: 90°; NYC: 89°
May 21, 1962: JFK: 90°; NYC: 87°

Bridgeport reached 87°. That broke the daily record of 85°, which was set in 1991 and tied in 1992.

Tomorrow will feature more unseasonable warmth. Temperatures will generally reach the upper 80s and lower 90s across much of the region. Exceptions would be coastal areas prone to sea breezes.

The dominant weather story into the closing week of May will be the synoptic impact of a strongly to occasionally severely negative PNA. That development will lead to a warmer to perhaps much warmer than normal second half of May. There will likely be additional days on which the temperature will make a run at 90° in parts of the region.

Today, the preliminary value of the PNA was -1.519. The PNA is forecast to remain at or below -1.000 until around May 24. During the May 16-31, 1991-2020 period, the mean temperature was 65.2° in New York City and 67.0° in Philadelphia. When the PNA was -1.000 or below, the average temperature was 67.7° in New York City and 69.3° in Philadelphia.

During the 1991-2020 period, 30% of days in New York City and 41% of days in Philadelphia had high temperatures of 80° or above. During the 1991-2020 period, 15% of days in New York City and 23% of days in Philadelphia had high temperatures of 85° or above. When the PNA was -1.000 or below during that period, 41% of days in New York City and 50% of days in Philadelphia had high temperatures of 80° or above. When the PNA was -1.000 or below during that period, 24% of days in New York City and 35% of days in Philadelphia had high temperatures of 85° or above.

As had been the case with April, the closing week of May could wind up warmer to much warmer than normal. In the four cases where the MJO reached Phase 1 at an amplitude of 2.000 or above in combination with a cool ENSO Region 3.4 anomaly during the May 1-10 period, as occurred this year, three wound up with warmer to much warmer than normal conditions. At New York City, the mean temperature during the closing 7 days of May was 72.7° during those three cases while it was 72.0° at Philadelphia. The 1991-2020 means were 67.9° and 69.7° respectively. Only May 25-31, 2013 (monthly ENSO Region 1+2 anomaly of -1.38°C) was cooler than normal. However, 90° heat arrived on May 29 in Philadelphia and May 30 in New York City during 2013.

The first 7-10 days of June could also start off warmer than normal. The MJO's passage through Phase 4 at an amplitude of 1.500 or above during the May 15-25 period coupled with ENSO Region 1+2 temperature anomalies above -1.0°C and below +1.0°C, as has been the case this year, has typically seen warmth in the East during the first 10 days of June. Cooler conditions typically prevailed when the ENSO Region 1+2 anomalies were outside that range.

Neutral ENSO conditions have now developed. The ENSO Region 1+2 anomaly was -0.6°C and the Region 3.4 anomaly was -0.3°C for the week centered around May 12. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.75°C and the ENSO Region 3.4 anomaly has averaged -0.38°C. Neutral ENSO conditions will likely prevail into at least mid-summer.

The SOI was +1.63 today.

The preliminary Arctic Oscillation (AO) figure was +1.092 today.

On May 20 the MJO was in Phase 4 at an amplitude of 1.863 (RMM). The May 19-adjusted amplitude was 1.915 (RMM).

In late April, the MJO moved through Phase 8 at an extreme amplitude (+3.000 or above). Only February 25, 1988 and March 18-19, 2015 had a higher amplitude at Phase 8. Both 1988 and 2015 went on to have an exceptionally warm July-August period. July-August 1988 had a mean temperature of 79.1°, which ranked 4th highest for that two-month period. July-August 2015 had a mean temperature of 78.9°, which ranked 5th highest for that two-month period. September 2015 was also the warmest September on record. The MJO's extreme passage through Phase 8 could provide the first hint of a hot summer.

Based on sensitivity analysis applied to the latest guidance, there is an implied 84% probability that New York City will have a warmer than normal May (1991-2020 normal). May will likely finish with a mean temperature near 64.6° (1.4° above normal).

 

Don do you have a list of occurrences where JFK has hit 100 and NYC hasnt?

 

[bluewave]

6 hours ago, LibertyBell said:

at this rate this could be like 1966 and JFK could go above 100 multiple times in the summer

 

This weekend actually looks like our last dry heat for a while. The next warm up on Wednesday is forecast to be more humid. So we may get back to the familiar 70° dewpoints. It would fit with the guidance showing better rain chances coming up. 

 

[CIK62]

The next 8 days are averaging 69degs.(58/78), or +3.0.

Month to date is  62.6[+0.6].         Should be 64.3[+1.2] by the 31st.

May 26 still showing in the 90's.        Holiday period  seems BN/Nor. and wet.   67 to 75 for highs, 1" rain.

Reached 88* by me yesterday.      JFK (93*) Thermometer must be  too near the tarmac.  lol.    I usually track better  with JFK.

72*(70%RH) here at 6am, thin overcast.        75* by 9am, m. clear now.       82* by Noon, cumulus clouds.         Made it to 90* at 4:30pm.      82*  at 9pm.

[Rtd208]

11 minutes ago, bluewave said:

This weekend actually looks like our last dry heat for a while. The next warm up on Wednesday is forecast to be more humid. So we may get back to the familiar 70° dewpoints. It would fit with the guidance showing better rain chances coming up. 

 

Memorial Day weekend is looking a cooler and wet. We could see rain/storms Friday, Saturday, Sunday and maybe Memorial Day itself.

[SACRUS]

75/61 now much more sun today should push the temps to 90 in most locations that haven't reached it already. Warmer spots look locked in for mid 90s.

  Brief but much cooler / cloudy on Monday in the 60s.  Tue - Thu next heat spike with Wed peaking with 850 temps >16c. 

 

From drought to deluge ?  Pending on flow, Upper level low may cut off around the east coast between May 28 - Ju 1.  Where and how that tracks will determine how much rain but looking unsettled for a period which matches well with recent transitions from dry to wet. 

Beyond there looking warm overall and heights higher on the east coast 6/3 0 on.

[donsutherland1]

Morning thoughts...

Today will be partly sunny and hot. Temperatures will likely reach the upper 80s to lower 90s in most of the region. A few areas could experience an afternoon or evening thundershower. Likely high temperatures around the region include:

New York City (Central Park): 91°

Newark: 95°

Philadelphia: 93°

Tomorrow will be noticeably cooler.

[donsutherland1]

8 hours ago, LibertyBell said:

Don do you have a list of occurrences where JFK has hit 100 and NYC hasnt?

 

These are the occurrences:

July 1, 1963: JFK: 102; NYC: 98

July 4, 1966: JFK: 101; NYC: 98

July 23, 1972: JFK: 100; NYC: 94

July 16, 1983: JFK: 100; NYC: 96

August 20, 1983: JFK: 100; NYC: 96

July 4, 2010: JFK: 101; NYC: 96

July 18, 2013: JFK: 100; NYC: 98

[bluewave]

13 hours ago, rclab said:

Good evening, Don/bluewave. Are there any efforts, ongoing, to address CPK readings. As always....

The overgrowth of vegetation blocking the sensors has been well known for a while now. They would need to move the ASOS to a clearing away from any trees. The video below shows the correct sitting of weather sensors in parks or more rural settings.

https://www.ncdc.noaa.gov/cdo-web/datasets/GHCND/stations/GHCND:USW00094728/detail

Obstruction Descriptions

OBSTRUCTIONS	BEGIN DATE¹	END DATE¹
TREES	2021-04-06	Present
TREES	2017-08-01	2021-04-06
TREE 020-340 deg 25-25 ft 20-54 deg	2016-06-15	2017-08-01
HYGR 090/4 TREES ENCIRLCE/25/20-54 IN FENCED ENCOLSURE 50 FT X 25 TH	1995-06-27	2016-06-15
UNIV 050/4 CRS 180/9 H083 SENSOR 200/8 TB 220/20 TREES ENCIRCLE/25/20-54 EQUIPMENT IN FENCED ENCLOSURE 50 FEET X 25 FEET	1992-01-01	1995-06-27

http://www.weather2000.com/ASOS/NYC_ASOS.html

Central Park Weather: Vegetative Overgrowth Affecting Weather Readings - WABC-TV

(New York-WABC, August 22, 2003) - Forecasting the weather is not easy.
Government equipment can often be blamed for giving faulty weather
information. As Bill Evans explains, a big culprit may be some of the
equipment buried in Central Park.

Rainfall, snowfall, and the temperature are all vital information
recorded 24 hours a day at the weather station located in the heart of
Central Park.

But meteorologists like Michael Schlacter have serious concerns about the
accuracy of the stations data. It sits amid overgrown vegetation and he
says thats the problem. The leaves can trigger snow gauges and trees can
warp rain and wind measurements. On this hot day, a temperature gauge is
in the shade instead of direct sunlight.

Michael Schlacter, Weather 2000: "Its kind of like driving a car
without a speedometer, odometer, and gas gauge. You are running with
false information."

The weather instruments at Belvedere Castle have long adorned the top.
There used to be a government meteorologist here in the city to keep an
eye on them. But now the nearest meteorologist is 60 miles that way.

But National Weather Service meteorologists say they knew the weather
readings in the park would never be as keenly accurate as the ones at
the airports where guidelines prevent foliage from being within 100 feet
of the station.

Schlacter: "We knew that at times we would have flaky readings, that
leaves would fall in gauges, that we would have problems with
visibility sensors."

[NWS Meteorologist-in-Charge Michael] Wyllie says the weather station is
there because it was historically significant to maintain its presence
in the park.

He says theres been a lot of growth because of the wet spring at so much
in fact that temperatures have routinely been recorded lower in the park
than at the airports.

Wyllie: "We are actually having a micro climate system there because of
the vegetation."

Imperfect perhaps but nonetheless the system provides the official record
of weather for the country's largest city. And Michael Schlacter says
its a city that deserves better.

Schlacter: "I think New Yorkers deserve a lot better, and I think they
deserve the best weather station money can buy."


Copyright 2003 ABC Inc., WABC-TV Inc.

 

 

[LoboLeader1]

Currently 76 here,  RH@ 65%. 

[crossbowftw3]

Mostly cloudy so far here, 72/63. Severe threat is marginal but worth watching the skies today.

[Rtd208]

Current temp 80/DP 65

[Rjay]

81/65

[rclab]

1 hour ago, bluewave said:

The overgrowth of vegetation blocking the sensors has been well known for a while now. They would need to move the ASOS to a clearing away from any trees. The video below shows the correct sitting of weather sensors in parks or more rural settings.

https://www.ncdc.noaa.gov/cdo-web/datasets/GHCND/stations/GHCND:USW00094728/detail

Obstruction Descriptions

OBSTRUCTIONS	BEGIN DATE¹	END DATE¹
TREES	2021-04-06	Present
TREES	2017-08-01	2021-04-06
TREE 020-340 deg 25-25 ft 20-54 deg	2016-06-15	2017-08-01
HYGR 090/4 TREES ENCIRLCE/25/20-54 IN FENCED ENCOLSURE 50 FT X 25 TH	1995-06-27	2016-06-15
UNIV 050/4 CRS 180/9 H083 SENSOR 200/8 TB 220/20 TREES ENCIRCLE/25/20-54 EQUIPMENT IN FENCED ENCLOSURE 50 FEET X 25 FEET	1992-01-01	1995-06-27

http://www.weather2000.com/ASOS/NYC_ASOS.html

Central Park Weather: Vegetative Overgrowth Affecting Weather Readings - WABC-TV

(New York-WABC, August 22, 2003) - Forecasting the weather is not easy.
Government equipment can often be blamed for giving faulty weather
information. As Bill Evans explains, a big culprit may be some of the
equipment buried in Central Park.

Rainfall, snowfall, and the temperature are all vital information
recorded 24 hours a day at the weather station located in the heart of
Central Park.

But meteorologists like Michael Schlacter have serious concerns about the
accuracy of the stations data. It sits amid overgrown vegetation and he
says thats the problem. The leaves can trigger snow gauges and trees can
warp rain and wind measurements. On this hot day, a temperature gauge is
in the shade instead of direct sunlight.

Michael Schlacter, Weather 2000: "Its kind of like driving a car
without a speedometer, odometer, and gas gauge. You are running with
false information."

The weather instruments at Belvedere Castle have long adorned the top.
There used to be a government meteorologist here in the city to keep an
eye on them. But now the nearest meteorologist is 60 miles that way.

But National Weather Service meteorologists say they knew the weather
readings in the park would never be as keenly accurate as the ones at
the airports where guidelines prevent foliage from being within 100 feet
of the station.

Schlacter: "We knew that at times we would have flaky readings, that
leaves would fall in gauges, that we would have problems with
visibility sensors."

[NWS Meteorologist-in-Charge Michael] Wyllie says the weather station is
there because it was historically significant to maintain its presence
in the park.

He says theres been a lot of growth because of the wet spring at so much
in fact that temperatures have routinely been recorded lower in the park
than at the airports.

Wyllie: "We are actually having a micro climate system there because of
the vegetation."

Imperfect perhaps but nonetheless the system provides the official record
of weather for the country's largest city. And Michael Schlacter says
its a city that deserves better.

Schlacter: "I think New Yorkers deserve a lot better, and I think they
deserve the best weather station money can buy."


Copyright 2003 ABC Inc., WABC-TV Inc.

 

 

Thank you so very much for the detailed and even explanation/discussion. You’ve made me nostalgic for the way information/news was formally reported, with content/facts being more important than opinion/bias. I’ve sent the video to my grandson who is already showing an interest in atmospheric science. As always ...

[bluewave]

28 minutes ago, rclab said:

Thank you so very much for the detailed and even explanation/discussion. You’ve made me nostalgic for the way information/news was formally reported, with content/facts being more important than opinion/bias. I’ve sent the video to my grandson who is already showing an interest in atmospheric science. As always ...

No problem. The Central Park sensors used to be located in direct sunlight before the trees created deep shade. My rough calculation is that this has created an artificial 2° to 3° average maximum temperature summer JJA cooling since 1971. Notice how the mean summer high temperature increase at the other local stations since 1971 has been +2.7°.The high temperature staying steady at NYC instead of increasing was a function of trees blocking the sun.

1971 to 2020 summer JJA high temperature increase 

NYC….82.9….82.9…..0.0

LGA…..81.0….84.9….+3.9

EWR….83.4….85.4….+2.0

JFK…..80.1…..82.3..+2.2

ISP…….78.5…..81.6..+3.1

HPN….79.0….81.6…+2.6

BDR….79.1…..81.4…+2.3

 

[forkyfork]

11 hours ago, forkyfork said:

forecast 850s are higher tomorrow and the nw downslope flow is stronger. i think ewr hits 98 and possibly ties the may record of 99

so far the dewpoints aren't mixing out despite the stronger nw flow. oh well

[nycwinter]

1 hour ago, forkyfork said:

so far the dewpoints aren't mixing out despite the stronger nw flow. oh well

felt more humid yesterday then today..

[nycwinter]

1 hour ago, bluewave said:

No problem. The Central Park sensors used to be located in direct sunlight before the trees created deep shade. My rough calculation is that this has created an artificial 2° to 3° average maximum temperature summer JJA cooling since 1971. Notice how the mean summer high temperature increase at the other local stations since 1971 has been +2.7°.The high temperature staying steady at NYC instead of increasing was a function of trees blocking the sun.

1971 to 2020 summer JJA high temperature increase 

NYC….82.9….82.9…..0.0

LGA…..81.0….84.9….+3.9

EWR….83.4….85.4….+2.0

JFK…..80.1…..82.3..+2.2

ISP…….78.5…..81.6..+3.1

HPN….79.0….81.6…+2.6

BDR….79.1…..81.4…+2.3

 

put the censors right outside the park so that you can claim their central park temps but the temps will be more realistic

[uncle W]

is the foliage around the parks prob effecting nightime lows also?...high or low...

[CIK62]

We have some clouds to get through.       Could be a break soon, then another area of cloudiness may pass by from nw to se.      Day should end clear.  

I have 82*(52%RH) at Noon

[psv88]

Clouds keeping temp to 84, off a high of 85. Not sure we see 90

[Rjay]

51 minutes ago, nycwinter said:

felt more humid yesterday then today..

But it wasn't. 

[donsutherland1]

Changes in Summer (June-August) Average High Temperatures (1971-00 vs. 1991-20 Means):

Bridgeport: +0.9°
Islip: +1.3°
New Brunswick: +1.4°
New York City-JFK: +1.0°
New York City-LGA: +1.6°
Newark: +0.8°
Poughkeepsie: +1.1°
White Plains: +1.0°

Average: +1.1°
Median: +1.1°
Standard Deviation: +0.3°

Trimmed Mean (excluding the highest and lowest changes): +1.1°
Second Trimmed Mean (excluding the two highest and lowest changes): +1.1°

New York City-Central Park: -0.1° (more than 3 sigma below the regional change excluding Central Park)

Note: The tree obstructions at Central Park were noted beginning in 1992

 

[SACRUS]

1PM Round up:

 

ACY: 90
EWR: 90
JFK: 89
New Brnswck: 89
PHL: 89
BLM: 88
TTN: 87
ISP: 84
NYC: 84
TEB: 84
LGA: 83

[SACRUS]

http://synoptic.envsci.rutgers.edu/site/imgs/vis_nj_anim.gif

 

[LibertyBell]

5 hours ago, donsutherland1 said:

These are the occurrences:

July 1, 1963: JFK: 102; NYC: 98

July 4, 1966: JFK: 101; NYC: 98

July 23, 1972: JFK: 100; NYC: 94

July 16, 1983: JFK: 100; NYC: 96

August 20, 1983: JFK: 100; NYC: 96

July 4, 2010: JFK: 101; NYC: 96

July 18, 2013: JFK: 100; NYC: 98

I know a few of these well!  I didn't realize it happened twice in 1983 though lol.  July 4th 2010 was one of my favorite July 4 ever, it was such a dry heat that it didn't even feel like 90 let alone 100.  I wish every summer was like that!

I remember the one in 2013 also and I think it was 2017 or 2018 JFK had back to back 99 and barely missed reaching 100 when NYC was stuck at 95 or 96.Had a heat index near 120 both days too, which was the highest on record for JFK.

1966 and 2010 were very similar, peak dry heat and downslope wind enabled JFK to top NYC.

 

[LibertyBell]

29 minutes ago, SACRUS said:

1PM Round up:

 

ACY: 90
EWR: 90
JFK: 89
New Brnswck: 89
PHL: 89
BLM: 88
TTN: 87
ISP: 84
NYC: 84
TEB: 84
LGA: 83

blah we can already tell today wont be anywhere near as hot as yesterday was

 

[LibertyBell]

46 minutes ago, donsutherland1 said:

Changes in Summer (June-August) Average High Temperatures (1971-00 vs. 1991-20 Means):

Bridgeport: +0.9°
Islip: +1.3°
New Brunswick: +1.4°
New York City-JFK: +1.0°
New York City-LGA: +1.6°
Newark: +0.8°
Poughkeepsie: +1.1°
White Plains: +1.0°

Average: +1.1°
Median: +1.1°
Standard Deviation: +0.3°

Trimmed Mean (excluding the highest and lowest changes): +1.1°
Second Trimmed Mean (excluding the two highest and lowest changes): +1.1°

New York City-Central Park: -0.1° (more than 3 sigma below the regional change excluding Central Park)

Note: The tree obstructions at Central Park were noted beginning in 1992

 

But NYC still did well in the amazing summer of 1993, so it had to be after that?