April 2020

[Ericjcrash]

24 minutes ago, LibertyBell said:

isn't that storm a cutter with temps in the 60s (talking about Monday)?

 

Late week.

[ebwx]

Nice quick shot of wet snowflakes, in East Brunswick at 4:42pm air temp 45.

[SRRTA22]

Man, definitely had some gusts in the hww criteria today

[LibertyBell]

3 minutes ago, SRRTA22 said:

Man, definitely had some gusts in the hww criteria today

for some reason we werent under any kind of advisory let alone warning

[donsutherland1]

5 hours ago, Isotherm said:

Verification. Below pasted from website. Brief analysis as time is limited.

 

https://www.lightinthestorm.com/

 

 

Brief Analysis:

Snowfall departures across the CONUS were generally congruous with expectations spatially – with the storm track favoring the Rockies, Upper Mid-west, and Northern New England for near or above normal snowfall. Snowfall forecast for Mid-Atlantic was accurate with well below average totals. NYC-BOS snowfall totals were forecasted to be below normal, with the reality featuring well below average totals.

Overall snowfall forecast for the CONUS = A-

Temperature wise, departures were well above normal across the East, versus a forecast for solidly above normal. The Southeast US and SW US were well forecast. The Plains/NW US were warmer than forecast.

Overall temperature forecast for the CONUS = C/C-

Local NYC region temperature forecast = C/C-

Local NYC snowfall forecast = B/B-

As to the pattern: forecast was +NAO, +EPO, -PNA, and near neutral AO. The only flaw in the pattern outlook was a more positive AO than expected for the second half of the winter, otherwise the z500 coincided very well with expectations.

Overall pattern, 500mb forecast for the NHEM = A-

 

Thus, the overall winter 2019-20 outlook yields a grade of: B-/B.

This was a hit, and a very good forecast overall, with the primary flaw being the magnitude of the warmth, thus lowering the final grade .

Very nice job, Isotherm. I hope you’re well.

[donsutherland1]

In the wake of yesterday's cold front, today was blustery with changeable skies and even some snow flurries. Snowfall amounts included:

Albany: Trace; Binghamton: 0.5"; New York City: Trace; Newark: Trace; and, Scranton: 0.2".

Through at least April 24, readings could average generally below normal to near normal with a few warmer than normal days across the Middle Atlantic and southern New England regions. Sunday and Monday are among the days that could see temperatures reach above normal levels. The Plains States will likely experience much colder than normal readings.

Past cases that saw the NAO average -0.750 or below during April 1-5 with warmth in the East, as occurred this month, saw the development of a trough in the East after April 10. That trough typically persisted in the means for 1-2 weeks. The 4/6 0z run of the EPS weeklies supports such a scenario.

Looking ahead to May, 73% of cases that saw one or more days where the NAO fell to -1.000 or below during April 1-10, 1950-2019, as was the case this April, wound up with a warmer than normal May. 

The ENSO Region 1+2 anomaly was +0.8°C and the Region 3.4 anomaly was +0.6°C for the week centered around April 1. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.75°C and the ENSO Region 3.4 anomaly has averaged +0.67°C. Neutral and occasionally warm ENSO conditions will likely prevail through at least the end of April.

The SOI was -1.88 today.

Today, the preliminary Arctic Oscillation (AO) figure was +0.907.

On April 9, the MJO was in Phase 7 at an amplitude of 1.614 (RMM). The April 8-adjusted amplitude was 1.226.

February 2020 saw the ENSO Region 1+2 anomaly increase by more than 0.50°C. Such a development has typically occurred before a warmer than normal summer. In all such cases, a warmer than normal spring was followed by a warmer than normal summer. Therefore, a warmer than normal summer is currently more likely than not. Should Spring wind up warmer than normal, a warm or even hot summer will be very likely.

Based on sensitivity analysis applied to the latest guidance, there is an implied 55% probability that New York City will have a cooler than normal April. April will likely finish with a mean temperature near 52.5°.

[SRRTA22]

8 hours ago, LibertyBell said:

for some reason we werent under any kind of advisory let alone warning

It is what it is. The wind was def good enough for atleast a wind advisory but blasi blah...Still had some good wind. Between 1-3pm it was really ripping out there. Gusts 40-60mph. Other then the fact of trying to walk into the wind...it was fun Lol . No damage nor any power outages. Between Irene and Sandy , all the weak trees are gone. 

[CIK62]

The next 8 days are averaging 51degs., or 1deg. BN.

Month to date is +2.7[52.2].        Should be +1.1[51.8] by the 20th.

The next 17 days are averaging   0.0[55.0](48/62).       This would put us at +1.0 by the 28th.

MONDAY AM  WIND POTENTIAL:

Mon 04/13 09Z

55 °

57 °

55 °

50 °

S 18

S 49

SSW 56

0.05

0.00

556

568

-13 °

5 °

8 °

1014

100 %

5 °

54

Mon 04/13 12Z

54 °

57 °

54 °

51 °

S 22

S 56

S 67

0.41

0.00

558

567

-11 °

7 °

9 °

1010

100 %

7 °

57

Mon 04/13 15Z

57 °

57 °

54 °

53 °

S 31

S 74

SSW 85

0.52

0.00

561

565

-11 °

9 °

11 °

1004

100 %

9 °

60

Mon 04/13 18Z

60 °

60 °

54 °

55 °

S 31

SSW 76

SSW 89

0.24

0.00

563

562

-11 °

10 °

13 °

999

100 %

10 °

63

Mon 04/13 21Z

69 °

69 °

60 °

54 °

SSW 22

SW 58

SW 67

0.10

0.04

562

561

-14 °

12 °

18 °

1000

75 %

8 °

66

Tue 04/14 00Z

62 °

71 °

60 °

45 °

W 20

WSW 54

WSW 63

0.00

0.01

558

562

-15 °

9 °

13 °

1005

64 %

2 °

69

Tue 04/14 03Z

57 °

62 °

57 °

40 °

W 20

W 45

WSW 49

0.00

0.00

553

561

-16 °

4 °

8 °

1010

0 %

-5 °

39* here at 6am.      40* by 8am.     41* at 9am.      43* at 10am.    47* by Noon.      50* by 2pm.    57* by 6pm.    51* by 11pm.

[bluewave]

Good model agreement on a near record April LLJ for Monday. Short term meso models should provide guidance on how much convection is able to develop. Stronger convection would mix down a portion of these  winds from aloft.

https://forecast.weather.gov/product.php?site=NWS&issuedby=BOX&product=AFD&format=CI&version=1&glossary=1&highlight=off

By 18Z Monday guidance
shows a southerly 850 mb LLJ of 90-100kts! GEFS ensemble guidance
shows v (southerly) component of the jet at 5-6 standard deviations
above normal.

 

[uncle W]

todays ao forecast is leaning more negative than yesterdays forecast...The nao has a few members falling off the table...I was counting on the nao getting positive later this month...some members are still positive so we wait...

[TriPol]

1 hour ago, uncle W said:

todays ao forecast is leaning more negative than yesterdays forecast...The nao has a few members falling off the table...I was counting on the nao getting positive later this month...some members are still positive so we wait...

Is this going to be like last year where we have a -NAO through the Spring and Summer which gives us a warm, hot summer again? I can't even begin to imagine how bad this summer is going to get.

[Ace]

21 minutes ago, TriPol said:

Is this going to be like last year where we have a -NAO through the Spring and Summer which gives us a warm, hot summer again? I can't even begin to imagine how bad this summer is going to get.

Last July was certainly hot, but last summer wasn't that bad. 2018 was much worse considering how humid it was that year.

[weathermedic]

High wind watch just posted for the area for Monday. Winds can gust up to 70mph. 

[bluewave]

Pretty impressive to see the NAM wind gust guidance come in at 70 mph or higher. 

 

[SnoSki14]

4 minutes ago, bluewave said:

Pretty impressive to see the NAM wind gust guidance come in at 70 mph or higher. 

 

I can see why the HWW was posted. GFS looked pretty impressive too.

[MJO812]

20 minutes ago, bluewave said:

Pretty impressive to see the NAM wind gust guidance come in at 70 mph or higher. 

 

Euro is similiar 

[MJO812]

Nam has gusts to 90 for eastern LI

[Barman49]

Anyone think the Euro's precip is overdone in NNJ?

 

Sent from my GM1925 using Tapatalk

 

 

 

 

[Ace]

4 minutes ago, Barman49 said:

Anyone think the Euro's precip is overdone?

No support from the other models, but I wouldn't be surprised to see the other models trend to it.  Seems to be multiple waves of rain on Monday and areas that get hit hard can probably expect over 2 inches.

On another note the winds are impressive at 925mb. If we can get into some get convective activity, could bring some of those damaging winds down.

 

 

 

[donsutherland1]

This afternoon, the temperature rose into the middle 50s under bright sunshine. As a result, people came outdoors to enjoy the fine spring day.

 

[Barman49]

No support from the other models, but I wouldn't be surprised to see the other models trend to it.  Seems to be multiple waves of rain on Monday and areas that get hit hard can probably expect over 2 inches.
On another note the winds are impressive at 925mb. If we can get into some get convective activity, could bring some of those damaging winds down.
 

 
 

Agreed. The NAM actually seemed to back off last run but I wouldn't be surprised to see it bump back up by tomorrow. Winds to me are the most exciting part of this as long as we don't have any power issues.

Sent from my GM1925 using Tapatalk

[crossbowftw3]

What are you all thinking for everywhere in between the actual low and the LLJ? Here where I'm at guessing only 40-50 at most with 50+ in higher elevations (Sullivan County)

[Rtd208]

20 minutes ago, Barman49 said:

Anyone think the Euro's precip is overdone in NNJ?

 

Sent from my GM1925 using Tapatalk

 

 

 

 

1-2" rainfall amounts are more reasonable IMO.

[Rtd208]

Slight risk not to far away. Now covering portions of NJ.

 

[Dan76]

A thread for Monday ?

[lee59]

Monday is looking real interesting at this point.

[hudsonvalley21]

[hudsonvalley21]

1 hour ago, Rtd208 said:

Slight risk not to far away. Now covering portions of NJ.

 

Their discussion for our area below,

Virginia through central and eastern Pennsylvania and New
   Jersey...

   Have expanded the SLGT risk farther north into this region. Areas of
   rain and thunderstorms will likely be ongoing north of a warm front
   from PA and NJ into southern New England. This activity will shift
   northeast during the morning allowing modest destabilization to
   occur in the pre-frontal warm sector with MLCAPE from 400-800 J/kg.
   Storms are expected to redevelop along cold front and in association
   with deeper forcing accompanying the northeast-ejecting shortwave
   trough. Wind profiles with 50+ kt effective bulk shear along with
   large 0-1 km hodographs will promote a threat for organized storms
   including supercells capable of damaging wind and a couple of
   tornadoes.

[donsutherland1]

Under bright sunshine, temperatures rose into the 50s across the region today.

Record warmth prevailed in parts of the United Kingdom, Ireland and France. In parts of the United Kingdom and Ireland, temperatures approached all-time April records. Daily records included:

Birmingham, UK: 75°; Brest, France: 75°; Cork, Ireland: 66°; Cranwell, UK: 75°; Dublin: 66°; East Midlands, UK: 72°; Humberside, UK: 75°; Jersey, UK: 75°; London-Gatwick: 75°; London-Heathrow: 75°; Manchester, UK: 66°; Paris-Charles de Gaulle: 77°; Paris-Le Bourget: 77°; Saint-Yan, France: 77°; Scampton, UK: 73°; Troyes, France: 77°; and, Yeovilton, UK: 77°.

Tomorrow will be partly sunny and noticeably milder. Temperatures will likely rise into the 60s.

Overnight, a rapidly deepening storm will track toward the Great Lakes. By Monday night, the storm could have a central pressure under 970 mb as it pushes through Quebec. Before then, this storm will spread periods of moderate to heavy rain into the region tomorrow night and Monday. Rainfall amounts will likely total 0.75"-1.75" with some locally higher amounts in excess of 2.00". Strong winds with gusts past 50 mph are likely on Monday. The potential also exists for some strong to possibly severe thunderstorms. Colder air should return for Tuesday.

Through at least April 24, readings could average generally below normal to near normal with a few warmer than normal days across the Middle Atlantic and southern New England regions. Sunday and Monday are among the days that could see temperatures reach above normal levels. The Plains States will likely experience much colder than normal readings. The potential exists for warming after April 24.

Past cases that saw the NAO average -0.750 or below during April 1-5 with warmth in the East, as occurred this month, saw the development of a trough in the East after April 10. That trough typically persisted in the means for 1-2 weeks.

Looking ahead to May, 73% of cases that saw one or more days where the NAO fell to -1.000 or below during April 1-10, 1950-2019, as was the case this April, wound up with a warmer than normal May. In addition, two-thirds of cases that saw the MJO reach Phase 8 at an amplitude of 2.000 or above during the April 5-20 period, as happened this month, saw a warmer than normal May. 

The ENSO Region 1+2 anomaly was +0.8°C and the Region 3.4 anomaly was +0.6°C for the week centered around April 1. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.75°C and the ENSO Region 3.4 anomaly has averaged +0.67°C. Neutral and occasionally warm ENSO conditions will likely prevail through at least the end of April.

The SOI was +5.19 today.

Today, the preliminary Arctic Oscillation (AO) figure was +0.895.

On April 10, the MJO was in Phase 8 at an amplitude of 2.068 (RMM). The April 9-adjusted amplitude was 1.613.

February 2020 saw the ENSO Region 1+2 anomaly increase by more than 0.50°C. Such a development has typically occurred before a warmer than normal summer. In all such cases, a warmer than normal spring was followed by a warmer than normal summer. Therefore, a warmer than normal summer is currently more likely than not. Should Spring wind up warmer than normal, a warm or even hot summer will be very likely.

Based on sensitivity analysis applied to the latest guidance, there is an implied 54% probability that New York City will have a cooler than normal April. April will likely finish with a mean temperature near 52.5°.

[MJO812]