April 2021

[SnoSki14]

Very California like weather and the best you'll ever see in Spring for us.

60s to low 70s with low humidity is pretty ideal for Spring...unless you have allergies of course.

I wonder if this will carry over into the summer and we see 100F+ temps.

[donsutherland1]

Tomorrow will be another mainly fair and mild day. Temperatures will likely top out in the upper 60s across the region. Some areas could again reach 70°. Afterward, it will become somewhat cooler. Then, temperatures could be confined mainly to the 50s in much of the region. Based on the latest guidance, no significant precipitation is likely into the weekend.

Some rain is possible this weekend followed by near seasonable temperatures.

Up north, excessive warmth will develop in northeastern Canada where some record high temperatures will be possible from tomorrow through Saturday.

The ENSO Region 1+2 anomaly was -1.1°C and the Region 3.4 anomaly was -0.5°C for the week centered around March 31. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.25°C and the ENSO Region 3.4 anomaly has averaged -0.63°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses.

The SOI was -7.72 today.

The preliminary Arctic Oscillation (AO) figure was -0.236 today.

On April 5 the MJO was in Phase 6 at an amplitude of 1.353 (RMM). The April 4-adjusted amplitude was 1.422 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 64% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 54.5° (1.5° above normal).

 

[psv88]

52 minutes ago, SnoSki14 said:

Very California like weather and the best you'll ever see in Spring for us.

60s to low 70s with low humidity is pretty ideal for Spring...unless you have allergies of course.

I wonder if this will carry over into the summer and we see 100F+ temps.

I’m getting crushed due to allergies. The dry air is brutal. My lungs are feeling the burn 

[JerseyWx]

3 hours ago, SnoSki14 said:

Very California like weather and the best you'll ever see in Spring for us.

60s to low 70s with low humidity is pretty ideal for Spring...unless you have allergies of course.

I wonder if this will carry over into the summer and we see 100F+ temps.

Gorgeous today, don't think you can get much better.  Wouldn't mind a hot and dry  (humidity wise) summer.

[LibertyBell]

21 hours ago, donsutherland1 said:

During the April 1982 blizzard, New York City (JFK: 8.0”; LGA” 8.2”; NYC: 9.6”) did not see any of its major stations quite reach 10”. Outside the City, Newark picked up 12.8” and Islip received 16.0”.

During the May 1977 snowfall, New York City saw a trace of snow. Some parts of New York State picked up 10” or more of snow e.g., Tannersville received 13.0” of snow.

Don why the big difference between Islip 16" and JFK 8"  It was an all snow event wasn't it?

 

[LibertyBell]

On 4/6/2021 at 4:43 PM, bluewave said:

I believe the all-time lowest relative humidity at Newark is 5% on 3-30-07

Newark/Liberty MOSUNNY   71   3   7 

https://www.wunderground.com/history/daily/us/nj/newark/KEWR/date/2007-3-30

5:51 PM

68 F

-5 F

5 %

How is it not in the summer when temps are warmer?

 

[LibertyBell]

21 hours ago, bluewave said:

JFK made it down to 10%. The relative humidity dropped to 21% on 4-17-02 at Newark. I believe that is the lowest relative humidity in modern times with a temperature over 90°. March and April typically have our lowest relative humidity readings of the year. It will be interesting to see if anyone can find the relative humidity during the July 1936 dust bowl heatwave.
 

EWR 4-17-02

2:51 PM

95 F

49 F

21 %

W

13 mph

18 mph

29.93 in

whats the record lowest humidity at NYC, LGA and JFK, Chris?

I would think the lowest should be in the summer when temps are their warmest and we have a nice downsloping dry wind.

 

[CIK62]

The next 8 days are averaging 57degs.(49/65), or about +5.0.       Range has increased due to higher highs and less rain coming, I suppose.

All models have under an inch for the  4/10-4/15 period now.

Today the whole period from 4/15 to 4/22  looks to have BN T's.     850mb T's stay sub 0*C at that time.

50*(63%RH) here at 6am.       54* by 8am.          57* by 10am, but back to 55* at 11am.          57* by 3pm.        62* at 5pm.        52* by 11pm.

[bluewave]

This is the first time since at least 1950 that NYC had a warmer than average first week of April with a high temperature under 40°. All the other years were around 10° colder for the first week of April. So like we saw over the winter, this south based blocking pattern is creating new and unusual weather patterns for us. 

 

Time Series Summary for NY CITY CENTRAL PARK, NY
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Lowest Max Temperature Apr 1 to Apr 7	Avg Temperature + Departure
1	1982-04-07	30	41.1  -7.9
2	1975-04-07	37	40.4  -8-6
3	2003-04-07	38	40.6  -8.4
4	2021-04-07	39	51.0  +2.0
-	1995-04-07	39	43.2  -5.8

[donsutherland1]

1 hour ago, LibertyBell said:

Don why the big difference between Islip 16" and JFK 8"  It was an all snow event wasn't it?

 

At the onset, some parts of the area saw some rain. Banding also played a role in the snowfall accumulations.

[donsutherland1]

Morning thoughts...

It will be mostly sunny and warm. High temperatures will likely reach the upper 60s and lower 70s in most of the region. Likely high temperatures around the region include:

New York City (Central Park): 70°

Newark: 70°

Philadelphia: 71°

Tomorrow will be party to mostly cloudy and somewhat cooler. Temperatures will likely top out in the upper 50s and lower 60s. A period of rain is likely during the weekend.

[LibertyBell]

1 hour ago, bluewave said:

This is the first time since at least 1950 that NYC had a warmer than average first week of April with a high temperature under 40°. All the other years were around 10° colder for the first week of April. So like we saw over the winter, this south based blocking pattern is creating new and unusual weather patterns for us. 

 

Time Series Summary for NY CITY CENTRAL PARK, NY
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Lowest Max Temperature Apr 1 to Apr 7	Avg Temperature + Departure
1	1982-04-07	30	41.1  -7.9
2	1975-04-07	37	40.4  -8-6
3	2003-04-07	38	40.6  -8.4
4	2021-04-07	39	51.0  +2.0
-	1995-04-07	39	43.2  -5.8

wow thats interesting!

 

which of those were ones that had snow....just 1982 and 2003?

 

[HailMan06]

3 hours ago, LibertyBell said:

How is it not in the summer when temps are warmer?

 

During summer the Bermuda high is more involved in our weather bringing in much more moisture from the Atlantic and Gulf of Mexico.

[uncle W]

48 minutes ago, LibertyBell said:

wow thats interesting!

 

which of those were ones that had snow....just 1982 and 2003?

 

1882 and 2003 had a relatively cool summer...I think the first 90 degree day came in July for both years...1982 had three hot weeks in July...otherwise it was quite cool...2003 was cool and wet to start and warm and humid to the end...

[bluewave]

1 hour ago, LibertyBell said:

wow thats interesting!

 

We are pretty much rewriting SST and air temperature climo following such a -AO winter. Notice how much warmer the Western Atlantic is now compared to 2010 and 2011. Those were the last two winters with such a -AO and peak values dipping below -5. There is supposed to be  a cold pool off the East Coast after  such a -AO winter. But instead, there are near record warm SSTs to our east. The blocking pattern this month so far is linking up with the WAR and boosting heights over the NE. So the average temperature during the first week of April was much warmer than the past years with a low max temperature under 40°. It also resulted in the near record low single digit RH values and highs that keep beating guidance.

4-6-21

4-6-11

4-6-10

[psv88]

Feels hot in the sun right now but only 65. No wind for a change 

[LibertyBell]

1 hour ago, bluewave said:

We are pretty much rewriting SST and air temperature climo following such a -AO winter. Notice how much warmer the Western Atlantic is now compared to 2010 and 2011. Those were the last two winters with such a -AO and peak values dipping below -5. There is supposed to be  a cold pool off the East Coast after  such a -AO winter. But instead, there are near record warm SSTs to our east. The blocking pattern this month so far is linking up with the WAR and boosting heights over the NE. So the average temperature during the first week of April was much warmer than the past years with a low max temperature under 40°. It also resulted in the near record low single digit RH values and highs that keep beating guidance.

4-6-21

4-6-11

4-6-10

I sense a pattern here.....didn't we also just have the warmest period with no high of 50 or above during the middle of winter?

 

[LibertyBell]

20 minutes ago, bluewave said:

Models shifted further north with the warm front on Sunday. So the warm spots could make a run on 80°. Quite a change from earlier model runs.

 

New run

 

Old run

 

 

so maybe less rain on sunday?

 

[donsutherland1]

1 hour ago, bluewave said:

We are pretty much rewriting SST and air temperature climo following such a -AO winter. Notice how much warmer the Western Atlantic is now compared to 2010 and 2011. Those were the last two winters with such a -AO and peak values dipping below -5. There is supposed to be  a cold pool off the East Coast after  such a -AO winter. But instead, there are near record warm SSTs to our east. The blocking pattern this month so far is linking up with the WAR and boosting heights over the NE. So the average temperature during the first week of April was much warmer than the past years with a low max temperature under 40°. It also resulted in the near record low single digit RH values and highs that keep beating guidance.

4-6-21

4-6-11

4-6-10

It’s possible that the slowing thermohaline circulation might be having some impact. 

[LibertyBell]

Just now, donsutherland1 said:

It’s possible that the slowing thermohaline circulation might be having some impact. 

that should also impact the gulf stream

[bluewave]

3 minutes ago, donsutherland1 said:

It’s possible that the slowing thermohaline circulation might be having some impact. 

Yeah, that was the conclusion of a recent study.

 

[Brian5671]

68 and sunny here-another bluebird sky.    

[bluewave]

7 hours ago, LibertyBell said:

so maybe less rain on sunday?

 

The latest Euro brings the warm front through around 7-8 am in Sunday with some rain. Then it has breaks of sun and areas south of the warm front make it into the 70s. It has a round of late afternoon  and evening convection as the atmosphere destabilizes behind the front.
 

 

[donsutherland1]

Tomorrow will be partly to mostly cloudy and somewhat cooler. High temperatures will likely reach the upper 50s and lower 60s. A period of rain is possible across the region during the weekend. Sunday could be quite mild. A thundershower cannot be ruled out.

An unseasonably cold air mass will move into the Plains States next week and then into the Southeast toward or by the following weekend. The position of the block will keep the coldest air away from the region. As a result, temperatures will likely continue to top out mainly in the upper 50s and lower 60s.

Up north, excessive warmth will continue in northeastern Canada where some record high temperatures will be possible through Saturday.

The ENSO Region 1+2 anomaly was -1.1°C and the Region 3.4 anomaly was -0.5°C for the week centered around March 31. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.25°C and the ENSO Region 3.4 anomaly has averaged -0.63°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses.

The SOI was +0.050 today.

The preliminary Arctic Oscillation (AO) figure was -0.426 today.

On April 6 the MJO was in Phase 6 at an amplitude of 1.454 (RMM). The April 5-adjusted amplitude was 1.352 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 70% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 54.7° (1.7° above normal).

 

[CIK62]

The next 8 days are averaging 52degs.(47/57), or just Normal.

Less than an inch of rain on all models again for 4/10 to 4/15.

50*(83%RH) here at 6am, overcast.        49* by 9am.        Been 50* to 52* the last 6 hours.

[donsutherland1]

Morning thoughts...

It will be partly to mostly cloudy and cooler today. High temperatures will likely reach the upper 50s and lower 60s in most of the region. Likely high temperatures around the region include:

New York City (Central Park): 60°

Newark: 61°

Philadelphia: 65°

Tomorrow will be mostly cloudy. There could be a shower. A period of rain is likely during Saturday night or Sunday.

[bluewave]

This was the first time that Newark dropped below freezing during the first week of April while recording three days of 70° or higher.
 

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

Rank	Ending Date	Number of Days Max Temperature >= 70 Apr 1 to Apr 7	Minimum  Temperature
-	2010-04-07	5	44°
-	2021-04-07	3	28°
-	2005-04-07	3	41°
-	1981-04-07	3	37°
-	1974-04-07	3	34°
-	1967-04-07	3	33°
-	1945-04-07	3	33°

[LibertyBell]

15 minutes ago, bluewave said:

This was the first time that Newark dropped below freezing during the first week of April while recording three days of 70° or higher.
 

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

Rank	Ending Date	Number of Days Max Temperature >= 70 Apr 1 to Apr 7	Minimum  Temperature
-	2010-04-07	5	44°
-	2021-04-07	3	28°
-	2005-04-07	3	41°
-	1981-04-07	3	37°
-	1974-04-07	3	34°
-	1967-04-07	3	33°
-	1945-04-07	3	33°

wow and it was 28, beating all those other years by a fair amount

[LibertyBell]

16 minutes ago, donsutherland1 said:

Morning thoughts...

It will be partly to mostly cloudy and cooler today. High temperatures will likely reach the upper 50s and lower 60s in most of the region. Likely high temperatures around the region include:

New York City (Central Park): 60°

Newark: 61°

Philadelphia: 65°

Tomorrow will be mostly cloudy. There could be a shower. A period of rain is likely during Saturday night or Sunday.

Looks like the sunny blue sky weather is gone for an extended period

[bluewave]

37 minutes ago, LibertyBell said:

wow and it was 28, beating all those other years by a fair amount

Unusual combination of strong south based block and UL east of New England. This produced the near all-time record low relative humidity values in the single digits. So the very dry downslope flow really warmed up as it reached the coast.