April 2021

[bluewave]

15 minutes ago, LibertyBell said:

Chris, I heard all this cold weather is because of an extreme super typhoon near the Philippines, winds near 200 mph?!  How come no one has been talking about this?

Also there's going to be an impressive late season snow event on Tuesday 3-6 inches from KC to Chicago, how far east will that get?

Looks like permanent warmth is about 7-10 days away?

 

It looks like the typhoon will track very slowly near the Philippines the next several days. So it may be another week before it can recurve back out into the Pacific and potentially cause a wave break. The main player right now is the record block over Western North America buckling the flow. 
 

 

 

[CIK62]

YO HO HO and a Bottle of Rum the new GFS is performing like a Bum.         There are your 80's.        The GEFS still does not show even a 70.

 

[Gravity Wave]

1 hour ago, bluewave said:

Model forecasts indicating a very impressive cold frontal passage on Wednesday. Temperatures quickly rise into the low 70s ahead of the front. The forecast soundings indicate near record surface to 500 mb lapse rates. So severe convection looks possible. This is followed by a quick temperature drop to near freezing just N and W of NYC Thursday morning. Lapse rates remain steep to above 700mb so 50+ mph gusts will be possible behind the cold front. 

 

 

Lapse rates are usually the missing ingredient for big severe outbreaks in this region, I remember the October 2018 PA tornado outbreak where they played a key role. If it hadn't been for the low instability (it was October after all) it would have been a memorable event.

https://en.wikipedia.org/wiki/Tornadoes_of_2018#October_2

[donsutherland1]

Today saw variably cloudy skies with readings topping out in the middle 50s. Tomorrow will be somewhat warmer. Monday and Tuesday could feature readings in the 60s on Monday and even the 70s on Tuesday. A sharp cold front will likely cross the region on Wednesday bringing a short period of much below normal readings.

The recent model runs have now turned colder for the remaining week of April. That development will bear watching.

The ENSO Region 1+2 anomaly was -0.5°C and the Region 3.4 anomaly was -0.5°C for the week centered around April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses.

The SOI was -4.54 today.

The preliminary Arctic Oscillation (AO) figure was +0.499 today.

On April 15 the MJO was in Phase 7 at an amplitude of 1.611 (RMM). The April 14-adjusted amplitude was 1.725 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 60% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 53.7° (0.7° above normal).

 

[LibertyBell]

31 minutes ago, donsutherland1 said:

Today saw variably cloudy skies with readings topping out in the middle 50s. Tomorrow will be somewhat warmer. Monday and Tuesday could feature readings in the 60s on Monday and even the 70s on Tuesday. A sharp cold front will likely cross the region on Wednesday bringing a short period of much below normal readings.

The recent model runs have now turned colder for the remaining week of April. That development will bear watching.

The ENSO Region 1+2 anomaly was -0.5°C and the Region 3.4 anomaly was -0.5°C for the week centered around April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses.

The SOI was -4.54 today.

The preliminary Arctic Oscillation (AO) figure was +0.499 today.

On April 15 the MJO was in Phase 7 at an amplitude of 1.611 (RMM). The April 14-adjusted amplitude was 1.725 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 60% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 53.7° (0.7° above normal).

 

Don looks like 30s for lows and 50s for highs on Thursday and then again the following Sunday and Monday?  What do you think of the two days in the mid 80s predicted on the 28th and 29th?

 

[LibertyBell]

3 hours ago, Gravity Wave said:

Lapse rates are usually the missing ingredient for big severe outbreaks in this region, I remember the October 2018 PA tornado outbreak where they played a key role. If it hadn't been for the low instability (it was October after all) it would have been a memorable event.

https://en.wikipedia.org/wiki/Tornadoes_of_2018#October_2

Some of our most memorable severe wx outbreaks have happened in October and November

 

[donsutherland1]

This afternoon, the weather was mostly cloudy at the New York Botanical Garden. The spring evolution continues uninterrupted.

[donsutherland1]

17 minutes ago, LibertyBell said:

Don looks like 30s for lows and 50s for highs on Thursday and then again the following Sunday and Monday?  What do you think of the two days in the mid 80s predicted on the 28th and 29th?

 

While that would fit with the recent MJO passage, I am somewhat skeptical especially given the other guidance. Last week, I was more bullish about such an outcome so to speak. It’s not out of the question, but not as likely as I had previously thought.

[LibertyBell]

5 minutes ago, donsutherland1 said:

While that would fit with the recent MJO passage, I am somewhat skeptical especially given the other guidance. Last week, I was more bullish about such an outcome so to speak. It’s not out of the question, but not as likely as I had previously thought.

I see, so 30s for lows Thursday and again Monday and Tuesday morning after that is more likely than 80s for the 28th and 29th?

 

[donsutherland1]

43 minutes ago, LibertyBell said:

I see, so 30s for lows Thursday and again Monday and Tuesday morning after that is more likely than 80s for the 28th and 29th?

 

The possibility of minimum temperatures in the 30s on Thursday and then the 26th and perhaps 27th are more likely than 80s. 

[CIK62]

The next 8 days are averaging 53degs.(44/61), or -3.0.

Month to date is  52.6[+1.7].         Should be about 52.8[+0.2] by the 26th.

CMC has a Trace of snow for the 22nd.      GFS out of the 80's and in the 70's for the 29th.

49*(62%RH) here at 6am, thin scattered overcast.          51* by 9am.        53* by 10am.       55* by Noon.       57* at 1pm.    60* at 2pm.     Got back down to 53* during PM, 57* at 8pm.

[SnoSki14]

Yeah I'm not seeing 80s anymore though we could see some really warm temps on Tuesday (mid 70s) ahead of the front. 

Looks like another strong -NAO in the LR to start May. If that holds we may be waiting till mid May or longer for 80s. 

[donsutherland1]

Morning thoughts...

Today will be partly sunny and milder. 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): 64°

Newark: 64°

Philadelphia: 64°

Tomorrow will be sunny and mild. The first half of next week will be noticeably warmer with readings well into the 60s with perhaps a day where they reach or exceed 70°.

At the same time, a storm could bring 2” or more of snow to Detroit on Tuesday into Wednesday. Since 1874, Detroit has had only four storms of 2” or more snow on or after April 20: May 21-22, 1883: 5.0”; April 29, 1909: 3.0”; May 9, 1923: 6.0”; April 23-24, 2005: 4.3”. Detroit’s most recent measurable snow on or after April 20 occurred on May 10, 2020 when 0.5” of snow fell.

[Rtd208]

At least I picked up "some" rain during the week. 

7 day total ending yesterday of 1.33"

[gravitylover]

This rain is making me unhappy

[nyrangers1022]

53 minutes ago, gravitylover said:

This rain is making me unhappy

Thought it wasn't supposed to rain?   Hoping it holds off because I put down some Scotts Weed and Feed this morning.   If it rains it will wash it away

[dave0176]

10 hours ago, SnoSki14 said:

Yeah I'm not seeing 80s anymore though we could see some really warm temps on Tuesday (mid 70s) ahead of the front. 

Looks like another strong -NAO in the LR to start May. If that holds we may be waiting till mid May or longer for 80s. 

Another crappy spring in the making. Guess I’ll have to wait for the switch to flip to all out summer once again. Unbelievable how April May and most of June are just crappy anymore.

[LongBeachSurfFreak]

2 hours ago, dave0176 said:

Another crappy spring in the making. Guess I’ll have to wait for the switch to flip to all out summer once again. Unbelievable how April May and most of June are just crappy anymore.

At lease we got some blocking this winter. The worst is when it’s warm all winter and we flip to a cool dreary spring with a mega -NAO. 

[Rtd208]

Have to wonder if things are setting up for a cooler/wetter summer instead of a hotter summer which some have been forecasting. We'll see if the heat switch gets turned on by mid May.

[SnoSki14]

2 hours ago, dave0176 said:

Another crappy spring in the making. Guess I’ll have to wait for the switch to flip to all out summer once again. Unbelievable how April May and most of June are just crappy anymore.

I disagree with that. They'll still be plenty of 70+ sunnier days. 

Personally I'd rather wait for the heat until it actually matters. 70s with some cooler days is ok for me.

[donsutherland1]

Tomorrow and Tuesday will be springlike days. The temperature could surge above 70° in much of the region on Tuesday. A sharp cold front will likely cross the region on Wednesday, possibly with a squall line, bringing a short period of much below normal readings. Thursday morning could see the temperature fall below 40° in New York City.

Meanwhile, a storm will likely bring accumulating snow to parts of the Great Lakes region on Tuesday into Wednesday. Detroit could see 2" or more of snow on or after April 20 for only the 5th time on record. Detroit's last measurable snowfall on or after April 20 occurred just last year on May 10, 2020 when 0.5" of snow was measured.

The ENSO Region 1+2 anomaly was -0.5°C and the Region 3.4 anomaly was -0.5°C for the week centered around April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses.

The SOI was -1.01 today.

The preliminary Arctic Oscillation (AO) figure was +0.191 today.

On April 17 the MJO was in Phase 7 at an amplitude of 1.749 (RMM). The April 16-adjusted amplitude was 1.573 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 62% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 53.8° (0.8° above normal).

 

[psv88]

1 hour ago, Rtd208 said:

Have to wonder if things are setting up for a cooler/wetter summer instead of a hotter summer which some have been forecasting. We'll see if the heat switch gets turned on by mid May.

We say this every year. And every year the summers are hot...

[TriPol]

2 hours ago, psv88 said:

We say this every year. And every year the summers are hot...

Last Summer wasn't that hot. When was the last time we hit 100+?

[LibertyBell]

On 4/17/2021 at 9:18 PM, donsutherland1 said:

The possibility of minimum temperatures in the 30s on Thursday and then the 26th and perhaps 27th are more likely than 80s. 

Don, this has been one of the colder Aprils, I've had my heat on all month and it looks like more cold is coming.  Isn't it going to be difficult to have an above normal month?

 

[LibertyBell]

9 hours ago, donsutherland1 said:

Tomorrow and Tuesday will be springlike days. The temperature could surge above 70° in much of the region on Tuesday. A sharp cold front will likely cross the region on Wednesday, possibly with a squall line, bringing a short period of much below normal readings. Thursday morning could see the temperature fall below 40° in New York City.

Meanwhile, a storm will likely bring accumulating snow to parts of the Great Lakes region on Tuesday into Wednesday. Detroit could see 2" or more of snow on or after April 20 for only the 5th time on record. Detroit's last measurable snowfall on or after April 20 occurred just last year on May 10, 2020 when 0.5" of snow was measured.

The ENSO Region 1+2 anomaly was -0.5°C and the Region 3.4 anomaly was -0.5°C for the week centered around April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses.

The SOI was -1.01 today.

The preliminary Arctic Oscillation (AO) figure was +0.191 today.

On April 17 the MJO was in Phase 7 at an amplitude of 1.749 (RMM). The April 16-adjusted amplitude was 1.573 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 62% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 53.8° (0.8° above normal).

 

Looks like the accumulating snow will make it to KC, Chicago, Detroit, Cleveland and Buffalo? What about the NE PA mountains Don?  Lows in the 20s are being predicted there.

Also with all this cold around all month how will we get an above normal month?

 

[LibertyBell]

9 hours ago, Rtd208 said:

Have to wonder if things are setting up for a cooler/wetter summer instead of a hotter summer which some have been forecasting. We'll see if the heat switch gets turned on by mid May.

NWS is predicting a hot May-June-July (60%+ chance).  One thing that may throw a monkey wrench into the works is this volcanic eruption in the Caribbean which released a lot of SO2 which is now starting to encircle the globe.  Though the question is, how much is the lag with this and how strong will the effect be?  It might be more of an influence on the winter time pattern rather than the upcoming summer.

 

[LibertyBell]

5 hours ago, TriPol said:

Last Summer wasn't that hot. When was the last time we hit 100+?

I think we should measure summers by number of 90 degree days.  100 degree days just aren't frequent enough.....although I do measure heat by a combo of both 90 degree and 100 degree days, so for a summer to be historic by my definition it has to have at least 30 90 degree days and at least 1 100 degree day.

 

 

[CIK62]

The next 8 days are averaging 54degs.(45/64), or -3.0.

Month to date is  52.8[+1.8].         Should be 53.2[+0.3] by the 27th.

All models have 1" to 2" of rain on the 25th.     Even the GEFS makes it into the 70's now about the 28th/29th period.    The OP is 5875m and 15C, which puts  it +9F over the ensemble mean for this time frame at 2M.

53*(59%RH) here at 6am, m. clear.       57* by 9am.        59* by 2pm.        57* by 4pm.           Made it to 61* around 6:30pm.

[bluewave]

It’s actually been a warmer than average April so far with numerous 70° days. But the cool downs after each warm up have created a cooler perception.  We make another run on 70° before the sharp cold front on Wednesday. This is when strong to locally severe convection will be possible across the region. Then another sharp cool down into the 30s with a freeze just N and W of NYC. This is followed by another rebound in temperatures with a coastal storm possible on Sunday. Longer range may come down to the typhoon interaction with the mid and higher latitude pattern. The OP GFS and EPS are hinting that the SE Ridge will try to flex near the end of the month. So that may be the next chance to reach 80° if the models don’t shift before then.
 

KEWR   GFSX MOS GUIDANCE   4/19/2021  0000 UTC                       
 FHR  24| 36  48| 60  72| 84  96|108 120|132 144|156 168|180 192      
 MON  19| TUE 20| WED 21| THU 22| FRI 23| SAT 24| SUN 25| MON 26 CLIMO
 X/N  67| 50  71| 52  58| 33  56| 39  65| 47  69| 51  66| 51  70 45 64
 

SE ridge builds near end of April?

[donsutherland1]

Morning thoughts...

Today will be partly sunny and warm. High temperatures will likely reach the middle and upper 60s in most of the region. Likely high temperatures around the region include:

New York City (Central Park): 66°

Newark: 67°

Philadelphia: 68°

Tomorrow will be sunny unseasonably warm. Temperatures will likely reach or exceed 70° in much of the region.

At the same time, a storm could bring 1”-3” of snow to Detroit on tomorrow into Wednesday. Detroit’s most recent measurable snow on or after April 20 occurred on May 10, 2020 when 0.5” of snow fell. 

Detroit’s daily snowfall records are:

April 20: 1.2”, 1947

April 21: 0.3”, 1978