May 2021

[bluewave]

It’s good to see that we now have supplemental 15 year climate normals for the first time. The 15 year snowfall average at Islip of 36.3 is now similar to the old 1981-2010 normals for portions of New England. The December 15 year average temperature is  now close to 40° in NYC. A 40° December  is similar to the old 1981-2010 normals around Washington DC. The new 15 year July temperature around 80° at LGA and EWR  is similar to the 1981-2010 average around DC. 

ISLIP LI MACARTHUR AP, NY

Get this data as .csv | .pdf 

 

Season	MAX TEMP (°F)	MIN TEMP (°F)	AVG TEMP (°F)	PRECIP (IN)	SNOW (IN)
Annual	61.8	45.8	53.8	47.42	36.3

 

NEW YORK CNTRL PK TWR, NY

Dec	45.0	34.4	39.7	4.88	4.6

 

NEW YORK LAGUARDIA AP, NY

Jul	87.4	72.8	80.1	4.47	0.0

 

NEWARK INTL AP, NJ

Jul	88.0	70.3	79.2	5.05	0.0

https://www.ncei.noaa.gov/access/us-climate-normals/

https://www.washingtonpost.com/weather/2021/05/04/noaa-new-climate-normals/

It used to be that the normals would give a great idea of what the climate has been like for someone’s 30-year career, so new resource managers could get up to speed quickly on how and why a more senior manager made the choices they did based on past climate,” McPherson said in an email.

“Now we’re seeing enough change from one decade to the next that we need to prepare managers differently. They need to understand these are not static, so the direction of change is as important, or more important, as the values of the normals themselves.”

NOAA has been experimenting with supplemental climate normals that may better reflect what to expect in the 2020s. Some researchers have argued that climatological periods shorter than 30 years could be more accurate for monthly temperature averages used in the near future. Thus, the new NOAA climate normals include a supplemental set of 15-year data for the period 2006-2020, a first for any climate-norms update.

[SACRUS]

Sun starting to breakthrough here and up to 65

[Santa Claus]

maybe this clearing will lead to some funderstorms later today

[CIK62]

Difference between Cape May area and Breezy Point area is 20 degrees at about Noon:

[crossbowftw3]

Into full sun here now. Even if the severe threat is overall low the heavy rain threat looks like the main threat overall.

[SACRUS]

72/62 getting humid.  Sun is in/out

[Rtd208]

Current temp 72/DP62

[FPizz]

74

[psv88]

Topped out at 65 here, never broke out of the clouds. 

Sucks when its warmer in Nova Scotia than Long Island. 

[SACRUS]

81/64 here.  850s at >15C argued for quick surge with any duration of sunshine

[doncat]

Made it to 75° earlier...back down to 67° now with a se wind. Rain total past two days of 0.86".

[bluewave]

Classic spring backdoor day. 

Highs

BDR…64°

ISP…..65°

LGA…69°

JFK….71°

EWR…75°
 

[LoboLeader1]

63 here as of 5PM, RH @ 74%

[psv88]

Now the sun comes out...unreal. 

[bluewave]

The fewest MJO winter phase 8-1 days followed by a new May phase 1 amplitude record. It’s tough to keep up with all these new weather extremes and swings. Back in February it was the historic AO/NAO reversal.

 

 

[donsutherland1]

The temperature rose into the 70s as far north as New York City and the 80s in Philadelphia. Farther south, portions of the Southeast and Middle Atlantic region saw very warm temperatures. At Richmond, the temperature rose to 90° today. At Norfolk, the temperature soared to 93°, which surpassed the previous daily record of 92°, which was set in 1887 and tied in 1892.

The number of 90° or above days last year and the five-year average for select cities is below:

Albany: 2020: 13 days; 5-Year Average: 13.6 days
Allentown: 2020: 24 days; 5-Year Average: 27.6 days
Baltimore: 2020: 46 days; 5-Year Average: 44.6 days
Boston: 2020: 14 days; 5-Year Average: 17.2 days
Bridgeport: 2020: 11 days; 5-Year Average: 13.4 days
Burlington: 2020: 20 days; 5-Year Average: 13.0 days
Harrisburg: 2020: 35 days; 5-Year Average: 30.6 days
Hartford: 2020: 39 days; 5-Year Average: 29.0 days
Islip: 2020: 8 days; 5-Year Average: 9.4 days
New York City-JFK: 2020: 12 days; 5-Year Average: 10.2 days
New York City-LGA: 2020: 34 days; 5-Year Average: 29.4 days
New York City-NYC: 2020: 20 days; 5-Year Average: 18.2 days
Newark: 2020: 31 days; 5-Year Average: 31.2 days
Philadelphia: 2020: 36 days; 5-Year Average: 34.6 days
Scranton: 2020: 5 days; 5-Year Average: 16.4 days
Washington, DC: 2020: 46 days; 5-Year Average: 50.8 days

Tomorrow will be another mild day, though not as warm as today. Showers and thundershowers are possible as a cold front moves across the region. The remainder of the week will likely feature near normal to somewhat cooler than normal temperatures. Such cool shots have often occurred with a cold ENSO Region 1+2 anomaly (-1.0°C in the latest weekly data).

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 comination 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 ENSO Region 1+2 anomaly was -1.0°C and the Region 3.4 anomaly was -0.4°C for the week centered around April 28. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.87°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool ENSO conditions are now developing. Neutral ENSO conditions will likely be in place by the end of spring.

The SOI was +7.91 today.

The preliminary Arctic Oscillation (AO) figure was -0.193 today.

On May 3 the MJO was in Phase 1 at an amplitude of 3.395 (RMM). The May 2-adjusted amplitude was 3.570 (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.

 

[Cfa]

13 hours ago, bluewave said:

It’s good to see that we now have supplemental 15 year climate normals for the first time. The 15 year snowfall average at Islip of 36.3 is now similar to the old 1981-2010 normals for portions of New England. The December 15 year average temperature is  now close to 40° in NYC. A 40° December  is similar to the old 1981-2010 normals around Washington DC. The new 15 year July temperature around 80° at LGA and EWR  is similar to the 1981-2010 average around DC. 

ISLIP LI MACARTHUR AP, NY

Get this data as .csv | .pdf 

 

Season	MAX TEMP (°F)	MIN TEMP (°F)	AVG TEMP (°F)	PRECIP (IN)	SNOW (IN)
Annual	61.8	45.8	53.8	47.42	36.3

 

NEW YORK CNTRL PK TWR, NY

Dec	45.0	34.4	39.7	4.88	4.6

 

NEW YORK LAGUARDIA AP, NY

Jul	87.4	72.8	80.1	4.47	0.0

 

NEWARK INTL AP, NJ

Jul	88.0	70.3	79.2	5.05	0.0

https://www.ncei.noaa.gov/access/us-climate-normals/

https://www.washingtonpost.com/weather/2021/05/04/noaa-new-climate-normals/

It used to be that the normals would give a great idea of what the climate has been like for someone’s 30-year career, so new resource managers could get up to speed quickly on how and why a more senior manager made the choices they did based on past climate,” McPherson said in an email.

“Now we’re seeing enough change from one decade to the next that we need to prepare managers differently. They need to understand these are not static, so the direction of change is as important, or more important, as the values of the normals themselves.”

NOAA has been experimenting with supplemental climate normals that may better reflect what to expect in the 2020s. Some researchers have argued that climatological periods shorter than 30 years could be more accurate for monthly temperature averages used in the near future. Thus, the new NOAA climate normals include a supplemental set of 15-year data for the period 2006-2020, a first for any climate-norms update.

It’s also very likely that LGA is the northernmost site in the country with a month averaging 80°F or better.

Redding Municipal Airport (40.51°N) in California is a bit warmer with a 15-year mean of 83.4°F, but LGA (40.78°N) is positioned slightly further north. KRDD’s latitude would put it near the southern tip of Staten Island.

[LibertyBell]

18 hours ago, bluewave said:

It’s good to see that we now have supplemental 15 year climate normals for the first time. The 15 year snowfall average at Islip of 36.3 is now similar to the old 1981-2010 normals for portions of New England. The December 15 year average temperature is  now close to 40° in NYC. A 40° December  is similar to the old 1981-2010 normals around Washington DC. The new 15 year July temperature around 80° at LGA and EWR  is similar to the 1981-2010 average around DC. 

ISLIP LI MACARTHUR AP, NY

Get this data as .csv | .pdf 

 

Season	MAX TEMP (°F)	MIN TEMP (°F)	AVG TEMP (°F)	PRECIP (IN)	SNOW (IN)
Annual	61.8	45.8	53.8	47.42	36.3

 

NEW YORK CNTRL PK TWR, NY

Dec	45.0	34.4	39.7	4.88	4.6

 

NEW YORK LAGUARDIA AP, NY

Jul	87.4	72.8	80.1	4.47	0.0

 

NEWARK INTL AP, NJ

Jul	88.0	70.3	79.2	5.05	0.0

https://www.ncei.noaa.gov/access/us-climate-normals/

https://www.washingtonpost.com/weather/2021/05/04/noaa-new-climate-normals/

It used to be that the normals would give a great idea of what the climate has been like for someone’s 30-year career, so new resource managers could get up to speed quickly on how and why a more senior manager made the choices they did based on past climate,” McPherson said in an email.

“Now we’re seeing enough change from one decade to the next that we need to prepare managers differently. They need to understand these are not static, so the direction of change is as important, or more important, as the values of the normals themselves.”

NOAA has been experimenting with supplemental climate normals that may better reflect what to expect in the 2020s. Some researchers have argued that climatological periods shorter than 30 years could be more accurate for monthly temperature averages used in the near future. Thus, the new NOAA climate normals include a supplemental set of 15-year data for the period 2006-2020, a first for any climate-norms update.

Something that I use for more tangible shifts....how are we looking in terms of 90 degree highs per period?  and has there also been an increase of 100 degree days or is the sample size too small to make a call on that?

 

[LibertyBell]

5 hours ago, Cfa said:

It’s also very likely that LGA is the northernmost site in the country with a month averaging 80°F or better.

Redding Municipal Airport (40.51°N) in California is a bit warmer with a 15-year mean of 83.4°F, but LGA (40.78°N) is positioned slightly further north. KRDD’s latitude would put it near the southern tip of Staten Island.

I would say that ordinarily we would expect at least 15 90 degree days to have a monthly average of 80,  I sure hope this isn't a case of warmer mins driving the avg temp rise instead of actual heat- as in, highs of 90 or higher.

 

[LibertyBell]

10 hours ago, donsutherland1 said:

The temperature rose into the 70s as far north as New York City and the 80s in Philadelphia. Farther south, portions of the Southeast and Middle Atlantic region saw very warm temperatures. At Richmond, the temperature rose to 90° today. At Norfolk, the temperature soared to 93°, which surpassed the previous daily record of 92°, which was set in 1887 and tied in 1892.

The number of 90° or above days last year and the five-year average for select cities is below:

Albany: 2020: 13 days; 5-Year Average: 13.6 days
Allentown: 2020: 24 days; 5-Year Average: 27.6 days
Baltimore: 2020: 46 days; 5-Year Average: 44.6 days
Boston: 2020: 14 days; 5-Year Average: 17.2 days
Bridgeport: 2020: 11 days; 5-Year Average: 13.4 days
Burlington: 2020: 20 days; 5-Year Average: 13.0 days
Harrisburg: 2020: 35 days; 5-Year Average: 30.6 days
Hartford: 2020: 39 days; 5-Year Average: 29.0 days
Islip: 2020: 8 days; 5-Year Average: 9.4 days
New York City-JFK: 2020: 12 days; 5-Year Average: 10.2 days
New York City-LGA: 2020: 34 days; 5-Year Average: 29.4 days
New York City-NYC: 2020: 20 days; 5-Year Average: 18.2 days
Newark: 2020: 31 days; 5-Year Average: 31.2 days
Philadelphia: 2020: 36 days; 5-Year Average: 34.6 days
Scranton: 2020: 5 days; 5-Year Average: 16.4 days
Washington, DC: 2020: 46 days; 5-Year Average: 50.8 days

Tomorrow will be another mild day, though not as warm as today. Showers and thundershowers are possible as a cold front moves across the region. The remainder of the week will likely feature near normal to somewhat cooler than normal temperatures. Such cool shots have often occurred with a cold ENSO Region 1+2 anomaly (-1.0°C in the latest weekly data).

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 comination 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 ENSO Region 1+2 anomaly was -1.0°C and the Region 3.4 anomaly was -0.4°C for the week centered around April 28. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.87°C and the ENSO Region 3.4 anomaly has averaged -0.45°C. Neutral-cool ENSO conditions are now developing. Neutral ENSO conditions will likely be in place by the end of spring.

The SOI was +7.91 today.

The preliminary Arctic Oscillation (AO) figure was -0.193 today.

On May 3 the MJO was in Phase 1 at an amplitude of 3.395 (RMM). The May 2-adjusted amplitude was 3.570 (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.

 

Wow this is interesting- Allentown has been averaging more 90 degree days than NYC/  Don both of those summers you mentioned were hot but not extreme, I don't believe either had any 100 degree days here and neither was among the top for number of 90 degree days?  They were just consistently very warm to hot without being extreme.  1988 could have been but the extreme heat was to our west, and Long Island and the city didn't reach 100 like they did in years like 1977, 1980, 1983, 1991, 1993, 1995, 1999, 2010, 2011, for example.

 

[CIK62]

The next 8 days are averaging 56degs.(48/64), or -5.0.

BN should last past mid-month.       Less rain showing too, over the next 15 days.

54*(92%RH) here at 6am,    FOG<1.0mi., streets wet         57* by Noon, fog mostly gone.          Reached 60* at 4:30pm.

[donsutherland1]

Morning thoughts...

It will be variably cloudy and cooler than yesterday. Showers and thundershowers are likely as a cold front approaches and moves across the region. The heaviest rainfall is likely to occur across upstate New York and northern New England.. Temperatures will likely reach the lower and middle 60s in most of the region. Southern New Jersey and southeastern Pennsylvania could see the temperature rise into the lower 70s. Likely high temperatures around the region include:

New York City (Central Park): 64°

Newark: 66°

Philadelphia: 72°

A sustained period of below normal to near normal temperatures will arrive tomorrow.

In terms of the 1991-2020 normal temperatures, December saw the biggest increase in monthly temperature in both New York City and Philadelphia relative to the previous 1981-2010 baseline. In New York City, the normal monthly temperature rose by 1.6°. In Philadelphia, it rose by 1.3°. No months were cooler in New York City (smallest change: +0.3° in March and November). November was 0.2° cooler in Philadelphia. In New York City, January, July, September, October, and December saw increases of 1.0° or above. Only December met that criteria in Philadelphia. The greatest warming over two months occurred during the December-January period in New York City and Philadelphia. The September-October period saw the second greatest warming for a two-month period. 

[bluewave]

2 hours ago, LibertyBell said:

Something that I use for more tangible shifts....how are we looking in terms of 90 degree highs per period?  and has there also been an increase of 100 degree days or is the sample size too small to make a call on that?

 

The minimums are increasing faster than the maximums across the region. So the number of 70° minimums has doubled or tripled from 1981 to 2020. This is the case at urban,rural, and suburban stations. My guess is that this is related to the big increase in humidity and clouds at night as the climate warms. Since the Central Park station has become so overgrown with vegetation, POU to our north now has more 90° days than NYC. But the NYC nighttime minimums are increasing just as fast as other stations. So you can see it’s an artificial shading effect due to poor sensor sitting under the trees and bushes.

Change in 90° highs and 70° lows 

……….1981….90°…..70°…….2020…….90°……70°

EWR…26/35….29/43

LGA….14/32….26/67

NYC….19/29…16/47

JFK…..11/29….11/40

ISP……..6/15……9/30

BDR……6/11……11/35

POU….12/3…..…19/9

BDL……14/6…….24/13

TTN…….18/17…..26/31

 

 

[SACRUS]

Looks like max temps <75 the next 12 days or so with a majority in the 60s,  before guidance indicates a more w/sw flow in the May 18 period (long range).  It is still looking more and more like a similar progression of 2016 May where the first two plus weeks were cooler than normal before the month ended much warmer.

[psv88]

Another cold dreary May. Yay. 

[SACRUS]

8 minutes ago, psv88 said:

Another cold dreary May. Yay. 

Despite the cool 20 days in 2016 the month as a whole winded up near normal.  I think we may see a similar progression , almost like an April replay.  But overall more cool or near normal days with persistent clouds looking likely though at least the 16th or so.

[bluewave]

This will be our first cool stretch in a while. So it only took a record breaking MJO event to pull It off. Goes to the recent theme of needing something extreme to get cooler than average temperatures. 
 

KEWR   GFSX MOS GUIDANCE   5/05/2021  0000 UTC                       
 FHR  24| 36  48| 60  72| 84  96|108 120|132 144|156 168|180 192      
 WED  05| THU 06| FRI 07| SAT 08| SUN 09| MON 10| TUE 11| WED 12 CLIMO
 X/N  65| 48  68| 47  63| 47  59| 45  62| 46  67| 47  66| 48  70 50 70
 TMP  59| 51  61| 52  56| 51  53| 50  54| 50  60| 52  59| 53  63      
 DPT  45| 35  30| 35  37| 39  34| 37  36| 40  34| 35  32| 37  39      
 CLD  OV| PC  PC| CL  OV| OV  OV| PC  OV| OV  PC| CL  PC| CL  PC      

[donsutherland1]

4 hours ago, LibertyBell said:

Wow this is interesting- Allentown has been averaging more 90 degree days than NYC/  Don both of those summers you mentioned were hot but not extreme, I don't believe either had any 100 degree days here and neither was among the top for number of 90 degree days?  They were just consistently very warm to hot without being extreme.  1988 could have been but the extreme heat was to our west, and Long Island and the city didn't reach 100 like they did in years like 1977, 1980, 1983, 1991, 1993, 1995, 1999, 2010, 2011, for example.

 

The combination of the prevailing pattern in the means and Central Park’s vegetation likely contributed to this recent outcome.

[nycwinter]

1 hour ago, psv88 said:

Another cold dreary May. Yay. 

beautiful weather chilly raw beats those days when it was in the 90;s in may..

[gravitylover]

I'd rather have 70 than 85 (or higher), keep the electric bills down with the AC not running. That said, today's 50 is not 70 and it sux.