IDA remnants-Moderate to isolated Major Impact (esp NJ-LI), general storm total 2-8" rainfall Wednesday-Thursday September 1-2 2021

[psv88]

3 minutes ago, Brian5671 said:

dead branch gets water logged and drops....

They had a foot of rain here in the past month. I dont buy it...power came back for now thankfully. 

[bluewave]

1 hour ago, LibertyBell said:

For some reason this reminds me of the overnight part of the storm we had in January 2011.....we had 5"/hr rates for a few hours and ended up with 19" when most were calling bust because precip was light or nonexistent during the day.

 

Actual busts are pretty rare in the age of better modeling. Models do a great job at identifying when heavy precipitation potential exists for the region. It’s just very difficult to pinpoint the exact locations for summer convection and winter snowstorm banding. Since I grew up in the 70s and 80s, one of my definitions off a bust is the models completely missing a storm. The most recent example of this was models  the day before the Jan 25, 2000 snowstorm forecasting no precipitation here. Another type of bust is getting the p-type wrong. Like the January 2008 event that would up mostly rain instead of snow. These two types of model busts were par for the course before the early 90s. While January 2015 was a big forecast amount miss, the blizzard just shifted to a further east part of the forum. NYC got lower amounts than forecast but still a significant snow. So all I really need to see from a model in the warm season is being correct with the the general heavy convection signal. I have learned to be patient on where the specific heaviest rainfall verifies. We often need to rely more on nowcast location of mesoscale features.

[Brian5671]

UKIE

[jm1220]

6 minutes ago, Brian5671 said:

UKIE

Yup. Quite the model war at the end. 

[NJwx85]

7 minutes ago, Brian5671 said:

UKIE

Been on and off torrential rain here all day so far. Some areas will have seen 2-3" before the main show happens which will easily drop an additional 4-6" areawide. 

[Brian5671]

1 minute ago, jm1220 said:

Yup. Quite the model war at the end. 

I'm inclined to split the difference.....

[NJwx85]

1 minute ago, jm1220 said:

Yup. Quite the model war at the end. 

Too much model hugging and not even meteorology. 

[LibertyBell]

28 minutes ago, jm1220 said:

It’s really about the rain over S PA now-how intact it is when it makes it to our region and whether it heads more ENE or NE. If more NE then the heaviest rain stays over CT and Hudson Valley. If it’s more easterly and the warm front can’t push as far, we all get drenched. 

we're getting sporadic heavy tropical rains right now that last for 10-15 min about once an hour.

 

[LibertyBell]

31 minutes ago, bluewave said:

Actual busts are pretty rare in the age of better modeling. Models do a great job at identifying when heavy precipitation potential exists for the region. It’s just very difficult to pinpoint the exact locations for summer convection and winter snowstorm banding. Since I grew up in the 70s and 80s, one of my definitions off a bust is the models completely missing a storm. The most recent example of this was models  the day before the Jan 25, 2000 snowstorm forecasting no precipitation here. Another type of bust is getting the p-type wrong. Like the January 2008 event that would up mostly rain instead of snow. These two types of model busts were par for the course before the early 90s. While January 2015 was a big forecast amount miss, the blizzard just shifted to a further east part of the forum. NYC got lower amounts than forecast but still a significant snow. So all I really need to see from a model in the warm season is being correct with the the general heavy convection signal. I have learned to be patient on where the specific heaviest rainfall verifies. We often need to rely more on nowcast location of mesoscale features.

The last two real busts in my memory are January 2008 "Heavy Snow Warning" and of course, March 2001.  I don't really remember January 2000 for some reason.....before March 2001, the one I remember most clearly was April 1997.  Before that we have to go back before the modern era......February 1989 and December 1989.  Both were extremely ugly misses here.  We seem to get a vast majority of these misses during La Ninas.....have you noticed that too?

For my most cherished positive memory bust it was a 30 hour snowfall which was just supposed to be a frontal passage and the front stalled just offshore and a storm formed along it and it just sat there and snowed in a very narrow band from Newark to Long Island, we got over 8 inches because it was wet snow during the day, and that was in February during the early 90s.

[Allsnow]

Euro is 2-5 inches for the area 

[pstar3182]

Good, keep going down. 

[Dark Star]

47 minutes ago, bluewave said:

Actual busts are pretty rare in the age of better modeling. Models do a great job at identifying when heavy precipitation potential exists for the region. It’s just very difficult to pinpoint the exact locations for summer convection and winter snowstorm banding. Since I grew up in the 70s and 80s, one of my definitions off a bust is the models completely missing a storm. The most recent example of this was models  the day before the Jan 25, 2000 snowstorm forecasting no precipitation here. Another type of bust is getting the p-type wrong. Like the January 2008 event that would up mostly rain instead of snow. These two types of model busts were par for the course before the early 90s. While January 2015 was a big forecast amount miss, the blizzard just shifted to a further east part of the forum. NYC got lower amounts than forecast but still a significant snow. So all I really need to see from a model in the warm season is being correct with the the general heavy convection signal. I have learned to be patient on where the specific heaviest rainfall verifies. We often need to rely more on nowcast location of mesoscale features.

If a storm is predicted, and misses by 100 miles, its a bust.  In fact some forecasters are persistent with the previous 48 hours outputs, that they can't revise their forecasts.  Easy for me to say as an armchair forecaster.  March 05, 2001 was a major bust when almost every forecaster stuck with the forecast, even after the snow had moved north and east of Manhattan.  Alan Kasper was the first to pick this up.

[SI Mailman]

Just need the rain to hold off til 630 here so I can get everybody's mail to them dry.

[jm1220]

15 minutes ago, pstar3182 said:

Good, keep going down. 

Euro actually got slightly wetter for NYC proper and LI. All systems go regardless for a ton of rain north of the city. 

[Yanksfan]

5 minutes ago, Dark Star said:

If a storm is predicted, and misses by 100 miles, its a bust.  In fact some forecasters are persistent with the previous 48 hours outputs, that they can't revise their forecasts.  Easy for me to say as an armchair forecaster.  March 05, 2001 was a major bust when almost every forecaster stuck with the forecast, even after the snow had moved north and east of Manhattan.  Alan Kasper was the first to pick this up.

Don’t. Ever. Say. That. Date. Again.

[NJwx85]

2 minutes ago, NutleyBlizzard said:

Don’t. Ever. Say. That. Date. Again.

That storm was child's play compared to this one...

[NJwx85]

Let's play a game called, Find the Warm Front

[bluewave]

18 minutes ago, Dark Star said:

If a storm is predicted, and misses by 100 miles, its a bust.  In fact some forecasters are persistent with the previous 48 hours outputs, that they can't revise their forecasts.  Easy for me to say as an armchair forecaster.  March 05, 2001 was a major bust when almost every forecaster stuck with the forecast, even after the snow had moved north and east of Manhattan.  Alan Kasper was the first to pick this up.

The heaviest snowfall axis for January 2015 would up about 60 miles further east than forecast the day before. I believe that is within the margin of error for 24 hr model forecasts. We only noticed this since NYC is the most densely populated part of the country. A similar miss out on the Great Plains would hardly make news since it could easily fall between the spread out population centers. January 2000 was my most recent memory of a big model bust. The forecast the day before was for no storm at all for NC up to New England. Parts of the NC had one of their biggest snowstorms on record. Jan 87 was a big model bust since we got 10” of snow instead of modeled snow quickly changing to rain. Jan 20, 78 had a nighttime forecast of rain heavy at times. But 12-18” of snow verified the next morning. So most of the model misses since the 2000 event have been minor in comparison. There were many other examples in the pre-1990 era of winter storm warming’s that verified as partly sunny or the moon visible through a thin cloud layer.

[Yanksfan]

3 minutes ago, NJwx85 said:

That storm was child's play compared to this one...

What made 3/5/01 so painful was the big hype of the storm. I’ll never forget the snowfall map Al Roker showing 2-3 feet for the eastern half of NJ, while the western half was 3-4 feet two days before the event! That bust forever changed TV forecasters methods when it comes to a potential major event. They have become much more conservative when it comes to predicting snowfall amounts. 

[SnoSki14]

Things are about to get wild soon. Convection is exploding to our SW now.

[NJwx85]

1 minute ago, NutleyBlizzard said:

What made 3/5/01 so painful was the big hype of the storm. I’ll never forget the snowfall map Al Roker showing 2-3 feet for the eastern half of NJ, while the western half was 3-4 feet two days before the event! That bust forever changed TV forecasters methods when it comes to a potential major event. They have become much more conservative when it comes to predicting snowfall amounts. 

I remember the storm well. I was in high school.

[NJwx85]

Location was near Edgewater, MD.

[larrye]

1 hour ago, psv88 said:

They had a foot of rain here in the past month. I dont buy it...power came back for now thankfully. 

We get power hits here in Tarrytown all the time from heavy rain. They last typically a few seconds or at most a few hours. But they happen repeatedly. It's almost like there's a ConEd box somewhere that water leaks into.

[lee59]

Not bad here so far, just some mostly light rain. .11 so far.

[NJwx85]

18z HRRR

[Rtd208]

 

[Brian5671]

18z NAM moved a bit south....6-8 inches N and W of NYC but the 2 inch line is further south-this run would drop a quick 3-4 inches in the city

[Allsnow]

3knam 4-7 for the area 

[Dark Star]

1 hour ago, NutleyBlizzard said:

Don’t. Ever. Say. That. Date. Again.

I hear thee.

[NJwx85]

All you need to look at now is the radar to see what's coming.