July 2020 General Discussions & Observations Thread

[doncat]

And I'm fairly sure this is the ASOS at LGA lol....

[bluewave]

18 minutes ago, doncat said:

And I'm fairly sure this is the ASOS at LGA lol....

 

LGA follows the sitting rules at airports. The actual sensors are on a strip of grass with no obstructions. It’s representative of that part of Queens when there is an offshore flow. But it’s right on the water with cooling breeze when the flow in onshore.

https://weather.gladstonefamily.net/site/search?site=KLGA

[doncat]

4 minutes ago, bluewave said:

LGA follows the sitting rules at airports. The actual sensors are on a strip of grass with no obstructions.  You can see how it’s representative for that part of Queens when there is an offshore flow. But it’s right on the water so a cooling breeze when the flow in onshore.

https://weather.gladstonefamily.net/site/search?site=KLGA

You think that's a good spot for weather equipment? surrounded by roads/runways within several feet, with a building close by to boot.

[bluewave]

4 minutes ago, doncat said:

You think that's a good spot for weather equipment? surrounded by roads/runways within several feet, with a building close by to boot.

The actual sensors are located on a grassy strip. All of NYC is within feet of roadways and buildings. So I don’t see anything at that location that varies much from Queens of the other parts of NYC. 
 

These are the guidelines for airport ASOS sittings.

https://www.faa.gov/documentLibrary/media/Order/6560_20c_ord.pdf

[tek1972]

Could we have a separate thread for weather sensor/temp discussion?

Sent from my SM-N975U using Tapatalk

[uncle W]

41 minutes ago, doncat said:

And I'm fairly sure this is the ASOS at LGA lol....

the water is on the other side of the upper runway...there has to be planes taxiing very close to the censors...

[doncat]

8 minutes ago, uncle W said:

the water is on the other side of the upper runway...there has to be planes taxiing very close to the censors...

Yeah and just the reflected and radiated heat from the roads/runways...no wonder they don't radiate.

[nycwinter]

2 hours ago, Stormlover74 said:

This September like weather was nice while it lasted 

i can see the light at the end of the tunnel it is already past the midway point of july.. summer days are going by fast...

[FPizz]

81 as the high today. Very pleasant 

[bluewave]

53 minutes ago, uncle W said:

the water is on the other side of the upper runway...there has to be planes taxiing very close to the censors...

I was wondering about that before I read this...

https://www.weather.gov/media/owlie/2018-ASOS.pdf

There are also some things that you would think affect the readings but generally don’t, such as jet exhaust. There are algorithms (computer code) in ASOS that take these quick fluctuations into account. These algorithms have been developed and tested to provide the most accurate and sensible data for a given sensor by using sampling over a period of time and other methods proven to weed out spikes in the sensor data that are caused by non-meteorological influences.

[doncat]

Only made it to 76° with the strong onshore flow.

[dWave]

2 hours ago, doncat said:

You think that's a good spot for weather equipment? surrounded by roads/runways within several feet, with a building close by to boot.

Maybe not total perfection, but within accepted standards, and for comparison sake is good since every other city is using their local airport.  A zoomed in satellite view in Google Maps of surrounding areas like Astoria, Jackson Heights, Flushing and across the river in Mott Haven, Hunts Point, East Harlem makes LGA look fairly representative. Also, for perspective using google maps measure distance tool, its about 60' to 150+ ft from the pavement going around.

On another note, couldn't ask for a much better mid July day than today. got to 80. Feels nice holding temps mainly in the 70s without it being b/c of rain.

 

[LibertyBell]

On 7/14/2020 at 8:28 PM, donsutherland1 said:

That was the highest I have seen anywhere.

Don do you think DC gets its new 90 day streak record?  Today was supposed to be close.....

 

[LibertyBell]

3 hours ago, doncat said:

You think that's a good spot for weather equipment? surrounded by roads/runways within several feet, with a building close by to boot.

scientifically speaking it's consistent if all the other measuring locations are airports.

airport=airport=airport

airport<>park

 

[LibertyBell]

3 hours ago, doncat said:

You think that's a good spot for weather equipment? surrounded by roads/runways within several feet, with a building close by to boot.

the most representative sites seem to be JFK for coastal Brooklyn and Queens and EWR for the rest of the area.  Both radiate far better than either NYC or LGA.

 

[LibertyBell]

9 hours ago, Cfa said:

If there won’t be any efforts to remedy the disaster that is KNYC, I’m all for LGA taking over as the “official” NYC station as it best represents the climate of NYC.

Either way, I hate seeing KNYC’s legacy being ruined by poorly maintained siting conditions, you’d think since it’s so “historically significant” these problems wouldn’t exist.

take the avg of all four or simply take the avg of EWR and JFK......

 

[LibertyBell]

9 hours ago, wdrag said:

Same w snowfall:  Airport measurements are generally not by NWS, but instead by someone for the NWS, within a mile or 2, and something like 100ft elevation -this since we went to ASOS in the early 90s. Snow measurements are not an FAA mandate.  Instead, as noted herein earlier,  NWS directs those with interest in climate stats to use nearby representative sites and develop a regional average for snowfall.  BUT, having worked in BOS (now BOX),  I know the Blue Hill Observatory about 10 mi south of BOS and elevation, home to the longest continuous weather observations in North America... had trimmed foliage nearby its sensors to keep the record similar.  Federal monies may not be available for something like this in CP, if ever approved by NYC etc, but for the largest city in the USA,  might still be worthwhile.

Walt I understand the historical significance but isn't the data tainted if the foliage isn't pruned back and/or removed?  How come no one from the NWS comes to do that or tells the park conservancy to do it?

It should be some kind of executive order lol

 

[LibertyBell]

On 7/15/2020 at 2:43 PM, donsutherland1 said:

You make an important point. I have been using NYC due to its long climate record, which dates back to 1869. However, there has been a pronounced tendency for Central Park to show fewer 90 degree days than would be implied by regional data, individually and as an average (EWR-JFK-LGA-NYC).

Perspective 1:

During the 1959-2019 period, the regression equation in which the cases from JFK, LGA, and EWR were treated as independent variables and the Central Park number was the dependent variable, the Central Park number was less than predicted on 56% cases. However, since 2000, that number was less than predicted in 80% cases. The coefficient of determination was 0.728.

Perspective 2:

During the 1959-2019 period, the regression equation in which the 4-city average (which included Central Park) was the independent variable and the Central Park number was the dependent variable, the Central Park number was less than predicted on 56% cases. However, since 2000, that number was less than predicted in 95% cases. The coefficient of determination was 0.834. That Central Park had a tendency to have fewer 90 degree days than expected even when it was included in the mix highlights a microclimate that has been diverging from overall recent trends. Central Park is warming overall, but the relationship of its 90 degree days relative to the rest of the region has been  changing.

I will add a four-site average comprised of JFK-LGA-NYC-EWR that better reflects the overall regional impact. The coefficient of determination for that average against the independent variables of JFK, LGA, and EWR is 0.977 and the standard error is < 1.3.

Here is the data for 90° days for Select Cities (through July 14):

Albany: 10 (2019: 12 days)
Allentown: 8 (2019: 24 days)
Baltimore: 21 (2019: 59 days)
Boston: 1 (2019: 15 days)
Burlington: 12 (2019: 8 days)
Harrisburg: 11 (2019: 33 days)
Islip: 1 (2019: 8 days)
New York City-JFK: 4 (2019: 7 days)
New York City-LGA: 12 (2019: 26 days)
New York City-NYC: 6 (2019: 15 days)
Newark: 10 (2019: 27 days)
Philadelphia: 14 (2019: 35 days)
Washington, DC: 23 (2019: 62 days)

New York City-Newark Average: 8 (2019: 19 days)
...Expected: 8 (based on JFK-LGA-EWR data)

 

 

wow nice statistical write up, Don!  If we were to only use one of the four sites, which is most representative?  EWR?  Or if we were to use an avg of two, would it be EWR+JFK?

[LibertyBell]

On 7/15/2020 at 12:43 PM, bluewave said:

Yeah, it was part of all the early season close in tropical activity. It will be interesting to see what things look like once we approach the peak of the season. Some of the seasonal models have an active pattern for the Gulf and East Coast.

 

there is only one very hot summer with an east coast up this way that I can think of Chris, and that was 1944.  That year really stands out for the hot summer (part of the 11 yr cycle of course) and the big east coast tropical hit.....

[Animal]

Super windy on the ridge line nw nj

[donsutherland1]

33 minutes ago, LibertyBell said:

Don do you think DC gets its new 90 day streak record?  Today was supposed to be close.....

 

Washington missed today.

[donsutherland1]

25 minutes ago, LibertyBell said:

wow nice statistical write up, Don!  If we were to only use one of the four sites, which is most representative?  EWR?  Or if we were to use an avg of two, would it be EWR+JFK?

For all its issues, I believe a four-city composite makes the most sense. JFK's susceptibility to sea breezes is much greater than that for the other three cities.

[donsutherland1]

Cooler weather prevailed for another day in the Mid-Atlantic region. Temperatures will begin to rise tomorrow. A widespread heat wave could overspread the region starting this weekend. Parts of the Baltimore-Washington could see temperatures approach or reach 100° at the peak of the heat wave.

With a high temperature of 87°, Washington, DC's 20-day heat wave came to an end. That was the second longest heat wave on record. Only July 25-August 14, 1980 and July 29-August 18, 1988 saw longer heat waves of 21-day durations.

The current predominantly warmer than normal pattern will likely persist through at least August, paving the way for a solidly warmer than normal summer throughout the region. Occasional short-lived cool shots remain possible. One or more heatwaves are likely in July across the region, including New York City.

The ENSO Region 1+2 anomaly was -0.8°C and the Region 3.4 anomaly was -0.1°C for the week centered around July 8. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.72°C and the ENSO Region 3.4 anomaly has averaged -0.25°C. Neutral-cool conditions will likely prevail through mid-summer. The probability of the development of a La Niña event during late summer or early autumn has increased in recent weeks.

The last time the six-week moving average for ENSO Region 1+2 was as cold as the current figure during July or August occurred in 2013. Winter 2013-14 had neutral-cool ENSO conditions. January and February featured ENSO Region 3.4 anomalies that were -0.50°C or below.

The SOI was -8.56.

Today, the preliminary Arctic Oscillation (AO) figure was -0.489.

On July 15, the MJO was in Phase 2 at an amplitude of 1.248 (RMM). The July 14-adjusted amplitude was 1.574.

The MJO has been in either Phase 1 or Phase 2 for 46 consecutive days.

Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period.

Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period.

Based on sensitivity analysis applied to the latest guidance, there is an implied 82% probability that New York City will have a warmer than normal July. July will likely finish with a mean temperature near 79.3°.

Finally, on July 15, Arctic sea ice extent fell to 6.996 million square kilometers (JAXA). That is the earliest date on record on which Arctic sea ice extent was less than 7.000 million square kilometers. The previous mark was July 19, 2011.

 

 

 

[LibertyBell]

13 minutes ago, donsutherland1 said:

For all its issues, I believe a four-city composite makes the most sense. JFK's susceptibility to sea breezes is much greater than that for the other three cities.

ah I see, I was thinking that JFK is more representative of coastal parts of NYC like southern Bklyn and southern Queens, and EWR is more representative of the other parts of the city.  Both are better radiational coolers than either NYC or LGA.

If we use a four location composite is the data still comparable to the four site composite prior to 1996 (before ASOS was used.)  And would 2010 rank as our hottest summer (and hottest month) on record both by avg temp and by number of 90 degree days?

 

[LibertyBell]

16 minutes ago, donsutherland1 said:

Cooler weather prevailed for another day in the Mid-Atlantic region. Temperatures will begin to rise tomorrow. A widespread heat wave could overspread the region starting this weekend. Parts of the Baltimore-Washington could see temperatures approach or reach 100° at the peak of the heat wave.

With a high temperature of 87°, Washington, DC's 20-day heat wave came to an end. That was the second longest heat wave on record. Only July 25-August 14, 1980 and July 29-August 18, 1988 saw longer heat waves of 21-day durations.

The current predominantly warmer than normal pattern will likely persist through at least August, paving the way for a solidly warmer than normal summer throughout the region. Occasional short-lived cool shots remain possible. One or more heatwaves are likely in July across the region, including New York City.

The ENSO Region 1+2 anomaly was -0.8°C and the Region 3.4 anomaly was -0.1°C for the week centered around July 8. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.72°C and the ENSO Region 3.4 anomaly has averaged -0.25°C. Neutral-cool conditions will likely prevail through mid-summer. The probability of the development of a La Niña event during late summer or early autumn has increased in recent weeks.

The last time the six-week moving average for ENSO Region 1+2 was as cold as the current figure during July or August occurred in 2013. Winter 2013-14 had neutral-cool ENSO conditions. January and February featured ENSO Region 3.4 anomalies that were -0.50°C or below.

The SOI was -8.56.

Today, the preliminary Arctic Oscillation (AO) figure was -0.489.

On July 15, the MJO was in Phase 2 at an amplitude of 1.248 (RMM). The July 14-adjusted amplitude was 1.574.

The MJO has been in either Phase 1 or Phase 2 for 46 consecutive days.

Last year, the MJO went through a very strong passage through Phase 1 during the closing days of May. About four weeks later, a warmer than normal pattern locked in and predominated through early autumn. This year, the MJO was in Phase 1 for 3 consecutive days with an amplitude of 1.500 or above during the June 1-3 period.

Last year, the SOI fell to -42.04 on June 22 when the MJO was in Phase 6. This year, the SOI plunged below -46.68 on June 5, its lowest level in more than three years. The dramatic plunge in the SOI could be the proverbial spark that kicks off a sequence of events leading to the development of a sustained warmer than normal period. The cases that saw both the MJO and SOI thresholds satisfied generally saw 10-20 days where the temperature reached or exceeded 90° in New York City during the July 1-August 31 period.

Based on sensitivity analysis applied to the latest guidance, there is an implied 82% probability that New York City will have a warmer than normal July. July will likely finish with a mean temperature near 79.3°.

Finally, on July 15, Arctic sea ice extent fell to 6.996 million square kilometers (JAXA). That is the earliest date on record on which Arctic sea ice extent was less than 7.000 million square kilometers. The previous mark was July 19, 2011.

 

 

 

oh no- if DC had hit 90 today they would likely have had it for 30+ straight days...oh well, there may be more opportunities, who knows they may start another 20+ day streak starting tomorrow!

 

[LibertyBell]

6 hours ago, JoshSnow said:

I do I love the saun it’s very healthy you just need to be well hydrated!

this sucks, I like very dry heat, humidity causes air pollution issues

and this damned sea breeze which looks cooler on the thermometer but doesn't feel cooler because the humidity is higher!

I wish they'd put in a sea wall to keep the "sea breeze" out!

 

[LibertyBell]

5 hours ago, Cfa said:

It isn’t as big of an issue at the local level since there’s plenty of other stations nearby to choose from, but on a larger regional/national/global level Central Park represents NYC.

None of NYC’s stations do a perfect job of capturing the city’s general climate/weather, they ultimately reflect only their particular microclimate. LGA, in my opinion, easily comes the closest, but since it sits directly on the water its conditions can shift dramatically with changing wind directions, unlike the majority of the city, same for JFK and JBL, meanwhile KNYC, which arguably has the best location of the four, has obs that are tainted and unreliable.

When I lived in Jamaica my microclimate was a mix of LGA and JFK, leaning more towards LGA in the summer and JFK in the winter. In Far Rockaway my microclimate matched JFK in all seasons, the main difference was on a few nights in the winter where it’d be 10+ degrees warmer.  Currently WNW of ISP where my highs in the summer are about 2°F warmer on average.

JFK is great for radiational cooling, much more like the south shore of Nassau County.  It also cools down faster in the fall during early season snowfall events ;-)

 

[SACRUS]

7/16

PHL: 83
TTN: 81
LGA: 80
ACY: 79
New Brnswck: 79
NYC: 78
EWR: 78
TEB: 78
JFK: 76
BLM: 76
ISP: 75

[donsutherland1]

2 hours ago, LibertyBell said:

ah I see, I was thinking that JFK is more representative of coastal parts of NYC like southern Bklyn and southern Queens, and EWR is more representative of the other parts of the city.  Both are better radiational coolers than either NYC or LGA.

If we use a four location composite is the data still comparable to the four site composite prior to 1996 (before ASOS was used.)  And would 2010 rank as our hottest summer (and hottest month) on record both by avg temp and by number of 90 degree days?

 

Yes. The data has been more stable. I will check out the summer data on Friday.

[wdrag]

10 hours ago, LibertyBell said:

Walt I understand the historical significance but isn't the data tainted if the foliage isn't pruned back and/or removed?  How come no one from the NWS comes to do that or tells the park conservancy to do it?

It should be some kind of executive order lol

 

I think the data is not tainted if foliage is similar over the years.  I don't want to get into the weeds on this, but CP has a problem if indeed it has become overgrown like this. Fortunately we have many other sites nearby with period of record beyond 50 years.  I think Blue Hill has handled it thoughtfully well to keep the record relatively intact, as in it's beginnings.