September 2023

[psv88]

14 minutes ago, Will - Rutgers said:

i was a student at the time and just happened to seize upon that one storm and those model runs and was telling people for weeks we were in trouble

never did it before or since, my college friends thought i was a weather savant instead of a lucky weenie

Same here. Except I was 28 

[psv88]

26 minutes ago, nycwinter said:

there is a difference between 68 southerly winds and humidity and 68 low humidity and a brisk northerly wind.

Yea 70 degree’s definitely cold for sure. 

[uofmiami]

16 minutes ago, bluewave said:

Yeah, the correction below is definitely what you want to see from a 3 run trend. But I would really like to know why the initial 102 hr forecast was so suppressed. There are people programming that model with some very advanced physics and math degrees. So it would be nice for one of them to join the forum and tell us what the  challenges are with East Coast storm tracks. Perhaps interactions between the polar Jet and Gulf Stream just are too hard for the state of the art technology to resolve. Maybe we can get luckier when the Euro upgrades to 4-5 km resolution and improves their convective schemes. And I hope AI can make some real advances with correcting model biases.

 

Wonder if the data sparse upstream of the pacific plays a role.  Feb 21 air travel wasn’t back to normal levels, so I’m sure missing that data could have played a role to some extent. 

[kat5hurricane]

What is with the yellow jackets this year especially late this summer? I got swarmed with them today.

[bluewave]

10 minutes ago, uofmiami said:

Wonder if the data sparse upstream of the pacific plays a role.  Feb 21 air travel wasn’t back to normal levels, so I’m sure missing that data could have played a role to some extent. 

Yeah, but I have seen versions of this from the Euro since after its hot streak around the time of Sandy. Sometimes it seems to get locked into a suppression forecasting pattern with storms that correct west over time. On other occasions, it’s way too far west and amped up. So I am not sure what is going on. I always read the latest ECMWF reports on performance. But seldom do we see regional skill forecasts for an area like the East Coast. It’s always very generalized with hemispheric or continental skill scores. But there was one write up in the January 2015 storm which the Euro had too far west. The Northeast Corridor is the most densely populated part of North America. So generalized skill scores for much wider geographic areas don’t  tell the full story. Something seemed to happen with the model around one of the updates after Sandy.  

[WX-PA]

3 hours ago, Allsnow said:

It’s definitely not what it use to be in years past. We have had it on our side several times the past few winters inside it’s 3-5 day wheelhouse. Unfortunately, it’s not that accurate in the medium range anymore. It has become very prone to big changes from run to run inside 5 days. It’s definitely the model I want in my side for a snowstorm but it’s just not as accurate anymore…

Their running it 4 times a day, I wonder if that has anything to do with it. I remember the days it ran only once at 12z at it was super accurate then.

[Stormlover74]

13 minutes ago, kat5hurricane said:

What is with the yellow jackets this year especially late this summer? I got swarmed with them today.

spike in the yellow jacket population can be attributed to various factors, according to Sequeira. Such factors include mild winters and warm summers

[Stormlover74]

Gfs quite wet

 

[FPizz]

49 this morning.  A beautiful breezy 70 now

[rclab]

1 hour ago, Will - Rutgers said:

wasps are bug cops

Good afternoon Will. …….and they never read you your rights. Stay well, as always ……

[Stormlover74]

[Brian5671]

1 hour ago, Stormlover74 said:

NE trend has begun

[SACRUS]

Up to 78 here off a low of 53

[jm1220]

38 minutes ago, Brian5671 said:

NE trend has begun

Could finally be one where east of the city is favored for the heavy rain. 

[Rmine1]

27 minutes ago, jm1220 said:

Could finally be one where east of the city is favored for the heavy rain. 

Blasphemy! 

[winterwx21]

1 hour ago, jm1220 said:

Could finally be one where east of the city is favored for the heavy rain. 

Yeah that's looking like a possibility. The 18z RGEM just has some light rain for us monday morning. The heavier rain for the afternoon with the coastal misses well to the east (central and eastern LI). Of course some other models get the heavy rain further to the west, so it's too early to call this one. Obviously we'll get a much better idea tomorrow. 

But no matter what happens with this monday, the weather for the rest of the week is going to be spectacular. Sunny with high temps mid to upper 70s and very low humidity. Probably the best stretch of weather for the year coming up. 

[SnoSki14]

3 hours ago, Brian5671 said:

NE trend has begun

We're straying from the WAR coastal hugger/inland tracks this year I see. 

Could be a good sign for winter if the WAR isn't as strong 

[qg_omega]

11 hours ago, bluewave said:

Pretty cool how the early season nor’easter now forecast for Monday was missed by earlier model runs. So wet and cool pattern to start the new week. We’ll take anything that resembles an actual fall pattern. Eastern sections should be favored. So if this was the winter, better snows east with western areas missing out.

New run now has our first nor’easter of fall on Monday

 

Old run just a frontal passage 

[jm1220]

1 hour ago, winterwx21 said:

Yeah that's looking like a possibility. The 18z RGEM just has some light rain for us monday morning. The heavier rain for the afternoon with the coastal misses well to the east (central and eastern LI). Of course some other models get the heavy rain further to the west, so it's too early to call this one. Obviously we'll get a much better idea tomorrow. 

But no matter what happens with this monday, the weather for the rest of the week is going to be spectacular. Sunny with high temps mid to upper 70s and very low humidity. Probably the best stretch of weather for the year coming up. 

Yup, of course 18z models look to be trending well out to sea with any significant rain. Guess we’ll see what happens. 

[nycwinter]

why is weather forecasting so bad a few days ago we were looking a week to 10 days without any rain now that has changed quickly.,

[etudiant]

13 minutes ago, nycwinter said:

why is weather forecasting so bad a few days ago we were looking a week to 10 days without any rain now that has changed quickly.,

Forecast reliability declines very rapidly going out beyond a couple of days. No one has a high skill forecast for even a working week, afaik.

That is what makes the effort so worthwhile, it's a really hard problem.

[donsutherland1]

Cirrus clouds on the fringes of Post-Tropical Storm Lee.

 

[donsutherland1]

Tomorrow will be fair and pleasant. However, rain will arrive on Monday and continue into Tuesday. A general 0.50"-1.50" of rain is likely.

In the medium and longer range, a warmer than normal pattern could develop in eastern North America.

The ENSO Region 1+2 anomaly was +2.9°C and the Region 3.4 anomaly was +1.6°C for the week centered around September 6. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +3.20°C and the ENSO Region 3.4 anomaly has averaged +1.38°C. El Niño conditions will likely continue to strengthen into the fall with the current East-based event transitioning to a basinwide El Niño for the upcoming winter.

The SOI was -13.19 today.

The preliminary Arctic Oscillation (AO) was -0.786 today.

On September 13 the MJO was in Phase 4 at an amplitude of 1.663 (RMM). The September 12-adjusted amplitude was 1.721 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 81% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 71.5° (2.3° above normal).

 

[SACRUS]

 

9/16

 

 

ACY: 79
EWR: 79
New Bnswck: 78
JFK: 78
PHL: 78
BLM: 77
LGA: 77
TEB: 77
TTN: 76
ISP: 75

NYC: 75

[winterwx21]

3 hours ago, jm1220 said:

Yup, of course 18z models look to be trending well out to sea with any significant rain. Guess we’ll see what happens. 

So far the 0z models not impressed. RGEM, HRRR and both NAMs giving just a light to moderate amount of rain. Those Euro runs were probably overdoing it by a lot. Right now I'd say this is looking like a quarter to half inch of rain for most. 

[winterwx21]

3 hours ago, nycwinter said:

why is weather forecasting so bad a few days ago we were looking a week to 10 days without any rain now that has changed quickly.,

Still a mostly dry 10 day period. Just 1 little period of rain (sunday night into monday) in the middle of the overall dry stretch. 

[forkyfork]

https://twitter.com/ECMWFbot

if you go through the runs it had the right idea most of the time except for a west shift that lasted about two days. if the whole setup were shifted west that could have meant an atlantic city landfall panic before turning back into a suffolk landfall

[jm1220]

21 minutes ago, winterwx21 said:

So far the 0z models not impressed. RGEM, HRRR and both NAMs giving just a light to moderate amount of rain. Those Euro runs were probably overdoing it by a lot. Right now I'd say this is looking like a quarter to half inch of rain for most. 

NAM would split screw most of us with an initial round for the NW areas then the coastal low well out to sea. 

Other models have this split screw as well. 

[Wxoutlooksblog]

4 hours ago, nycwinter said:

why is weather forecasting so bad a few days ago we were looking a week to 10 days without any rain now that has changed quickly.,

The pattern is transitioning into fall. And yes in a very short time-frame we've gone from tracking Lee to tracking the arrival of an autumn air mass into the Great Lakes. The models are struggling. A few days ago the models were depicting a warm to very warm finish to September and start to October. It does not appear that way now. It could change again but I wouldn't bet on it. The endless summer is going to end.

WX/PT

[Rjay]

6 hours ago, donsutherland1 said:

Cirrus clouds on the fringes of Post-Tropical Storm Lee.