April 2021

[donsutherland1]

5 hours ago, LibertyBell said:

Too bad no more 30s like we had last May.  Don, when was the last 30s last year, was it May 10th, and how low did we get in NYC and JFK, 36-38?  I think both had a T of snow too, on Friday and Saturday?

 

 

2020’s last 30s occurred on May 10 at JFK and NYC and May 9 at LGA. There was a trace of snow at all three sites on May 9 (the changeover of the rain occurred after 1 am; the afternoon saw additional snow showers and a minor snow squall in parts of the region).

[ForestHillWx]

It’s 29 here and we woke up to snow on car tops and roofs. I’m not too interested in 90s, just need it to get back above freezing before too much more damage is done. 

[uncle W]

last May NYC had temps in the 30's for the first time since 1978...then in October NYC had a temp of 32 for the first time since 1988...I would not be surprised if NYC gets into the 30's again before Summer...

[nycwinter]

went out this morning wearing my winter coat and gloves it felt refreshing !

[psv88]

34 this morning, terrible. 

[crossbowftw3]

barely 40 degrees on a persistent breeze. awful, hard to believe that in five days we will see 80 degrees

[LibertyBell]

10 hours ago, donsutherland1 said:

2020’s last 30s occurred on May 10 at JFK and NYC and May 9 at LGA. There was a trace of snow at all three sites on May 9 (the changeover of the rain occurred after 1 am; the afternoon saw additional snow showers and a minor snow squall in parts of the region).

So there were two separate bouts of snow, one was after the changeover, and the other was later the following day during snow showers and squalls?  Did any of these sites report a coating or was it all nonaccumulating brief snow showers, Don?  Did the temps drop at NYC or JFK to lower than what we had this morning?

 

[LibertyBell]

9 hours ago, uncle W said:

last May NYC had temps in the 30's for the first time since 1978...then in October NYC had a temp of 32 for the first time since 1988...I would not be surprised if NYC gets into the 30's again before Summer...

wasn't that the shortest freeze free period we've had?

 

[LibertyBell]

10 hours ago, SnoSki14 said:

90F potential in the works given how temps tend to overperform?

I wonder if the early heat is a sign of really hot summer.

Looks like it will only get to 70 here?

 

[donsutherland1]

The temperature could fall into the 30s for one more day tomorrow morning. If so, that will likely be the last time(s) the temperature falls into the 30s in Central Park until next fall. The afternoon will be fair and noticeably milder. The weekend could start out quite mild with readings well into the 60s and perhaps the lower 70s.

April will likely close with much above normal temperatures. The guidance has now moved into good agreement that the month will close with highs generally in the 70s. The potential for an 80° reading as far north as New York City exists.

This outcome would be consistent with the MJO's having moved through Phase 6 at a very high amplitude during the April 1-15 period. Since 1974, there were 7 cases where the MJO reached Phase 6 at an amplitude of 1.500 or above during April 5-15, as was the case this year. Only 1981 had an April 20-30 maximum temperature below 80° (75°). The average highest figure for such cases was 81.3°. The MJO's ongoing passage through Phase 7 at a very high amplitude is consistent with an outcome that typically yields 1-2 80° days.

The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.4°C for the week centered around April 14. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.33°C and the ENSO Region 3.4 anomaly has averaged -0.47°C. Neutral-cool ENSO conditions are now developing. Neutral ENSO conditions will likely be in place by the end of spring.

The SOI was +7.21 today.

The preliminary Arctic Oscillation (AO) figure was -0.181 today.

On April 20 the MJO was in Phase 7 at an amplitude of 2.096 (RMM). The April 19-adjusted amplitude was 2.119 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 90% 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).

 

[donsutherland1]

1 hour ago, LibertyBell said:

So there were two separate bouts of snow, one was after the changeover, and the other was later the following day during snow showers and squalls?  Did any of these sites report a coating or was it all nonaccumulating brief snow showers, Don?  Did the temps drop at NYC or JFK to lower than what we had this morning?

 

Yes, there were two different times when it snowed on May 9. None of the NYC area sites reported measurable snow.

[uncle W]

2 hours ago, LibertyBell said:

wasn't that the shortest freeze free period we've had?

 

NYC only went down to 34 in May of last year...32 on October 31st...1976 had a short season with mid 20's the second week in April and upper 20's near the end of October...

[LoboLeader1]

34 here as of 6:30 this AM.

[CIK62]

The last 8 days of April are averaging 57degs.(48/66), or just Normal.

Month to date is  53.1[+1.4].        April should end near  54.1[+1.1].

GFS now serving up highs in the 50's where it showed the 70's and  up to 94 for days.        Sunday rain still 0.5" to 1.0".         Heavy rain next Sunday too with those lower temperatures.

39*(49%RH) here at 6am, m. clear.(was 43 at midnight).      40* at 7am.      43* by 9am.        50* by Noon.       59* by 3pm.         61*(30%RH) at 4pm.      Reached 66*(26%RH) at 6pm.

[donsutherland1]

Morning thoughts...

At 7 am, the temperature was 39° in New York City’s Central Park. That will very likely be the last temperature in the 30s there until some time next fall.

Today will be partly to mostly sunny and noticeably milder than yesterday. High temperatures will likely reach the lower 60s in most of the region. Likely high temperatures around the region include:

New York City (Central Park): 62°

Newark: 65°

Philadelphia: 63°

Tomorrow will be partly cloudy and even warmer. There are growing indications on the guidance that the closing days of April could feature much above normal temperatures.

[bluewave]

Another day with a big diurnal temperature range. Our high temperatures usually beat guidance with such  low dewpoints and humidity. MOS numbers have mid 60s today in the warm spots. So maybe somebody can get close to 70°.
 

KEWR   GFS MOS GUIDANCE    4/23/2021  0600 UTC                      
 DT /APR  23      /APR  24                /APR  25             /     
 HR   12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 00 06 
 X/N              65          46          68          51       63    
 TMP  42 53 62 65 62 56 51 48 53 63 66 65 62 57 54 53 54 56 60 56 49 
 DPT  22 18 17 19 23 29 31 32 35 33 32 34 36 40 43 44 45 45 45 38 33 

 

[LibertyBell]

14 hours ago, uncle W said:

NYC only went down to 34 in May of last year...32 on October 31st...1976 had a short season with mid 20's the second week in April and upper 20's near the end of October...

wow 1976 must've been unimaginably cold compared to today's standards.....funny thing is they had the three straight 90s in April just like 2002 did.  What was JFK's lowest last May?  I can't find it.

This cold is much less prominent, only got down to 36 (still beat the 37 record from 2013)

[LibertyBell]

3 hours ago, bluewave said:

Another day with a big diurnal temperature range. Our high temperatures usually beat guidance with such  low dewpoints and humidity. MOS numbers have mid 60s today in the warm spots. So maybe somebody can get close to 70°.
 

KEWR   GFS MOS GUIDANCE    4/23/2021  0600 UTC                      
 DT /APR  23      /APR  24                /APR  25             /     
 HR   12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 00 06 
 X/N              65          46          68          51       63    
 TMP  42 53 62 65 62 56 51 48 53 63 66 65 62 57 54 53 54 56 60 56 49 
 DPT  22 18 17 19 23 29 31 32 35 33 32 34 36 40 43 44 45 45 45 38 33 

 

I think this kind of consistent low dew point heat is a great sign for the summer 

 

[tek1972]

Another day with a big diurnal temperature range. Our high temperatures usually beat guidance with such  low dewpoints and humidity. MOS numbers have mid 60s today in the warm spots. So maybe somebody can get close to 70°.
 

KEWR   GFS MOS GUIDANCE    4/23/2021  0600 UTC                      DT /APR  23      /APR  24                /APR  25             /     HR   12 15 18 21 00 03 06 09 12 15 18 21 00 03 06 09 12 15 18 00 06 X/N              65          46          68          51       63    TMP  42 53 62 65 62 56 51 48 53 63 66 65 62 57 54 53 54 56 60 56 49 DPT  22 18 17 19 23 29 31 32 35 33 32 34 36 40 43 44 45 45 45 38 33 

 

Not here lol. 50 at 12PM
:/

Sent from my SM-N986U using Tapatalk

[Brian5671]

models shifting south with sunday's storm-we're now on the northern fringe on the Euro and GFS.

[bluewave]

25 minutes ago, tek1972 said:

Not here lol. 50 at 12PM
:/

Sent from my SM-N986U using Tapatalk
 

Even Long Island should make it to at least 60° today. But as usual, Newark is the warm spot. Already 56° there with another 5 hours of warming to come. So mid 60s look like a good bet there.

Newark Liberty MOSUNNY   56  21  25 W15G31    

[winterwx21]

13 minutes ago, Brian5671 said:

models shifting south with sunday's storm-we're now on the northern fringe on the Euro and GFS.

Although 12z NAM came north with the heavier rain amounts, compared to last night's run. It gives NYC close to an inch.  RGEM also gives NYC a good three quarters of an inch. Hopefully GFS is off with the heavier amounts staying south. We could use a good soaking.

[LibertyBell]

1 hour ago, bluewave said:

Even Long Island should make it to at least 60° today. But as usual, Newark is the warm spot. Already 56° there with another 5 hours of warming to come. So mid 60s look like a good bet there.

Newark Liberty MOSUNNY   56  21  25 W15G31    

But with a dry wind doesn't that mean land breeze?  There should be no sea breeze here today.

I really wish we could artificially heat up the near coastal waters, temps in the 40s are absolutely offensive right now.

 

[gravitylover]

1 hour ago, Brian5671 said:

models shifting south with sunday's storm-we're now on the northern fringe on the Euro and GFS.

That .2" the other day was pretty useless, we need a good soaker. Everything is leafing out, grass is popping and it has been windy so the soil is dry, even 4-6" down it's moist not wet. 

[Brian5671]

15 minutes ago, gravitylover said:

That .2" the other day was pretty useless, we need a good soaker. Everything is leafing out, grass is popping and it has been windy so the soil is dry, even 4-6" down it's moist not wet. 

12z Euro is very dry for you, maybe .20 more.  Coastal areas get .5 to maybe .75

[winterwx21]

5 minutes ago, Brian5671 said:

12z Euro is very dry for you, maybe .20 more.  Coastal areas get .5 to maybe .75

12z Euro looks good for a decent soaking. It gives NYC about .75, similar to RGEM, and gets the half inch line well up into northern NJ. GFS is probably too far south with the rain amounts. The other models are in agreement on a good half inch to 1 inch soaking.

[sn0w]

18z NAM just moved well south with Sunday' rain.... 12z had over a half inch here and .75 to an inch around the city.

18z only gets 0.5" to Central NJ with the 1" all the way down by ACY

[Brian5671]

18 minutes ago, sn0w said:

18z NAM just moved well south with Sunday' rain.... 12z had over a half inch here and .75 to an inch around the city.

18z only gets 0.5" to Central NJ with the 1" all the way down by ACY

yeah the CMC and RGEM sniffed it out 2 days ago, then went back north, now it's all trending south

[donsutherland1]

Under bright sunshine, the temperature rose into the lower and middle 60s today. The weekend could start out quite mild with readings well into the 60s and perhaps the lower 70s. However, a storm passing to the south of the region could bring some rain to parts of the region on Sunday.

April will likely close with much above normal temperatures. The guidance has now moved into good agreement that the month will close with highs generally in the 70s. The potential for an 80° reading as far north as New York City exists. Tuesday and Wednesday could be the warmest days in a region stretching from the Great Lakes area to the Northeast.

This outcome would be consistent with the MJO's having moved through Phase 6 at a very high amplitude during the April 1-15 period. Since 1974, there were 7 cases where the MJO reached Phase 6 at an amplitude of 1.500 or above during April 5-15, as was the case this year. Only 1981 had an April 20-30 maximum temperature below 80° (75°). The average highest figure for such cases was 81.3°. The MJO's ongoing passage through Phase 7 at a very high amplitude is consistent with an outcome that typically yields 1-2 80° days.

Both the dynamical guidance and statistical measures that incorporate ENSO and the forecast teleconnections are in agreement that the first half of May will likely be warmer than normal in the region.

The ENSO Region 1+2 anomaly was -0.9°C and the Region 3.4 anomaly was -0.4°C for the week centered around April 14. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.33°C and the ENSO Region 3.4 anomaly has averaged -0.47°C. Neutral-cool ENSO conditions are now developing. Neutral ENSO conditions will likely be in place by the end of spring.

The SOI was +12.40 today.

The preliminary Arctic Oscillation (AO) figure was -0.181 today.

On April 21 the MJO was in Phase 7 at an amplitude of 2.048 (RMM). The April 20-adjusted amplitude was 2.096 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 92% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 54.6° (1.6° above normal).

 

[CIK62]

The last 7 days of April are averaging 64degs (55/73) or +6.5.

Month to date is  53.0[+1.2].        April should end at 55.5[+2.5].

Still about 0.40" to 1.0" rain tomorrow.     Model T performance is erratic and useless.       At any rate,  every model (5 out of 6) has 80+ for Wed. 4/28, except the Euro Ens.---as of the 0Z runs.

50*(47%RH) here at 6am, m. clear.         54* by 9am.       59* by Noon.      62* by 1pm.      65* by 2pm.        SE breeze and filtered sun, dropped T to 59* at 3pm.      55* by 6pm, nasty feel.