IDA remnants OBS-nowcasts (storm total rain and/or unusual flooding, wind damage-power outage, gusts ~45+ MPH) Wed-Thu morning Sept 1-2, 2021

[GrindOutWins]

57 minutes ago, CoastalWx said:

If this occurred 40 miles NW, nobody would be talking like you are. It’s unfortunate it all came together over NY metro.

I don't know if that's entirely true. You're saying "if this occurred 40 miles NW" - NW of where? Effects were felt from the Philly Metro on east, throughout almost all of NJ, the entirety of the greater NYC region, into the Lower and Mid Hudson Regions, up into the Capital District, east into Vermont, all of CT, all of MA, and parts of Eastern Maine. This wasn't a localized event. It was the complete opposite and that's what's most remarkable about it. You don't see sudden, flash flooding and wedge tornadoes spread over the entire Northeast like that anywhere in recorded, modern weather history. What non winter event was even remotely close to this? 

All of this, combined with the death/casualty toll - as well as cost - is something that's going to make this one for the books. In the northeast, you don't expect things to change that drastically, that quickly. It's just once or twice in a lifetime. 

edit: May 30/31, 1998: This was probably the most extreme, most widespread non winter event any of us can remember in the Northeast. What happened yesterday is just so far beyond that it's incredible. I honestly didn't think I'd see something like what just occurred in my lifetime. Not throughout the entire northeast. Who knows what tomorrow will bring? 

[GrindOutWins]

40 minutes ago, LibertyBell said:

The question is are they happening more frequently now? Well, to answer that in a different way, our average precip seems to be going way up if you compare 30 year precip norms now vs let's say a few decades ago.  I hate it.  There is nothing I dislike more than sticky, muggy tropical humid weather lol.

It hasn't led to a winter event corresponding with some of these flooding events in 11 years now. That's the one big caveat. I don't know what else can be deduced from that except that eventually there's going to be a winter event on the scale of what we just saw. Eventually. 

[Intensewind002]

This is a vid my dad took yesterday as he was driving, or attempted to drive really, to work. I think it’s the LIE but not exactly sure

https://onedrive.live.com/?authkey=!ACfOCntL1MBIt2c&cid=8A40D87C289A6855&id=8A40D87C289A6855!3947&parId=8A40D87C289A6855!1912&o=OneUp
 

 

[GrindOutWins]

One question: Why does August and September of 2011 (?) get lost in the shuffle? I spent a ton of time driving all across orange, putnam, and westchester counties that late summer. There was another clear 5"+ rainfall over the entire northeast. Anyone remember this? 

edit: There was actually a huge rainstorm in October followed by "Snowtober" a week later (2011). I can't remember weather this wild since then but I definitely know that the entirely of that period I'm talking about didn't cause the level of devastation that this event just did. 

[donsutherland1]

The top hourly rainfall figures were:

NYC: 3.47”

EWR: 3.62”

[GrindOutWins]

1 minute ago, donsutherland1 said:

The top hourly rainfall figures were:

NYC: 3.47”

EWR: 3.62”

Right. "Maybe" one or two other events like that since 1900. 

[donsutherland1]

2 minutes ago, GrindOutWins said:

Right. "Maybe" one or two other events like that since 1900. 

The old record was 3.05” on September 4, 1913.

[eduggs]

6 hours ago, forkyfork said:

Duration (intensity) was the key to local flash flooding, not so much the totals. The 4-6" that occurred in NEPA through SENY was spread over approx. 12 hours, whereas the majority of the 5-8"+ across EPA, CNJ, NYC metro, and into SCT fell in a 3-5 hr period. 

[LibertyBell]

1 hour ago, GrindOutWins said:

It hasn't led to a winter event corresponding with some of these flooding events in 11 years now. That's the one big caveat. I don't know what else can be deduced from that except that eventually there's going to be a winter event on the scale of what we just saw. Eventually. 

I mean we did have the giant 30+ inch snowstorm in Jan 2016.  What an extreme winter that was, from record warm December to that snow bomb to below zero in February for the first time since the 40s.

 

[LibertyBell]

1 hour ago, GrindOutWins said:

I don't know if that's entirely true. You're saying "if this occurred 40 miles NW" - NW of where? Effects were felt from the Philly Metro on east, throughout almost all of NJ, the entirety of the greater NYC region, into the Lower and Mid Hudson Regions, up into the Capital District, east into Vermont, all of CT, all of MA, and parts of Eastern Maine. This wasn't a localized event. It was the complete opposite and that's what's most remarkable about it. You don't see sudden, flash flooding and wedge tornadoes spread over the entire Northeast like that anywhere in recorded, modern weather history. What non winter event was even remotely close to this? 

All of this, combined with the death/casualty toll - as well as cost - is something that's going to make this one for the books. In the northeast, you don't expect things to change that drastically, that quickly. It's just once or twice in a lifetime. 

edit: May 30/31, 1998: This was probably the most extreme, most widespread non winter event any of us can remember in the Northeast. What happened yesterday is just so far beyond that it's incredible. I honestly didn't think I'd see something like what just occurred in my lifetime. Not throughout the entire northeast. Who knows what tomorrow will bring? 

also Labor Day 1998 we had an F2 tornado here!  I would also argue for November 1989 which was a horrendous severe weather event.

States of emergency in PA, NJ and NY, this was definitely not localized.

[LibertyBell]

1 hour ago, CoastalWx said:

We are getting warmer. And that means more moisture. But could it also be an unlucky stretch too? The 50s had some rough floods as well. It’s tough to point fingers and Blame it on CC.

50s were crazy however the magnitude of 3"+ events and how much more frequent they are is whats the difference.

 

[LibertyBell]

1 hour ago, GrindOutWins said:

One question: Why does August and September of 2011 (?) get lost in the shuffle? I spent a ton of time driving all across orange, putnam, and westchester counties that late summer. There was another clear 5"+ rainfall over the entire northeast. Anyone remember this? 

edit: There was actually a huge rainstorm in October followed by "Snowtober" a week later (2011). I can't remember weather this wild since then but I definitely know that the entirely of that period I'm talking about didn't cause the level of devastation that this event just did. 

Hey I mentioned August 2011

[HeadInTheClouds]

8 minutes ago, eduggs said:

Duration (intensity) was the key to local flash flooding, not so much the totals. The 4-6" that occurred in NEPA through SENY was spread over approx. 12 hours, whereas the majority of the 5-8"+ across EPA, CNJ, NYC metro, and into SCT fell in a 3-5 hr period. 

Yup. I got 5 inches but it was spread out over about 16 hours and there were no problems. 

[LibertyBell]

2 hours ago, uncle W said:

as bad as the storms were this Summer the record for the biggest rain fall still stands...

11.83" 09/21-23/1882

11.80" 10/08-10/1903

..9.19" 11/07-08/1977

..8.45" 04/15-16/2007

..8.19" 08/21-23/2021

..7.76" 09/13-14/1944

..7.19" 09/01-02/2021

..7.01" 10/12-13/2005

I know 1903 was a hurricane that curved into ACY like Sandy did but what happened in 1882 and 1977?

1944 was extremely impressive too, big hurricane hit.

 

[donsutherland1]

14 minutes ago, LibertyBell said:

I mean we did have the giant 30+ inch snowstorm in Jan 2016.  What an extreme winter that was, from record warm December to that snow bomb to below zero in February for the first time since the 40s.

 

It was the first subzero reading since 1994.

[LibertyBell]

2 minutes ago, donsutherland1 said:

It was the first subzero reading since 1994.

No I meant in the month of February.....haven't seen that in a long time.

 

[donsutherland1]

1 minute ago, LibertyBell said:

No I meant in the month of February.....haven't seen that in a long time.

 

Ok. Thanks.

[Cfa]

1 hour ago, donsutherland1 said:

The top hourly rainfall figures were:

NYC: 3.47”

EWR: 3.62”

Both higher than my 3.38” event total.

[LibertyBell]

25 minutes ago, Cfa said:

Both higher than my 3.38” event total.

It dried out as it came east lol

 

[TriPol]

Does anyone realize that the March 2001 curse has been broken? Usually when that is brought up, a bust is in store for our area, or if one isn't and someone brings it up, a bust occurs. March 2001 was brought up the other day. We did not bust. The 20-year curse has been broken.

[LibertyBell]

10 minutes ago, TriPol said:

Does anyone realize that the March 2001 curse has been broken? Usually when that is brought up, a bust is in store for our area, or if one isn't and someone brings it up, a bust occurs. March 2001 was brought up the other day. We did not bust. The 20-year curse has been broken.

dude that curse was broken with the 2002-03 winter lol

 

[nyrangers1022]

8 hours ago, GrindOutWins said:

One question: Why does August and September of 2011 (?) get lost in the shuffle? I spent a ton of time driving all across orange, putnam, and westchester counties that late summer. There was another clear 5"+ rainfall over the entire northeast. Anyone remember this? 

edit: There was actually a huge rainstorm in October followed by "Snowtober" a week later (2011). I can't remember weather this wild since then but I definitely know that the entirely of that period I'm talking about didn't cause the level of devastation that this event just did. 

2011 we had Irene, and Lee flood us out.  Lost power for like 3 hours.  That October snowstorm really shook us up.  Can't remember how much snow, probably around 8-12 inches of solid paste, wiped out the power grid here for days up to a couple weeks.  After that, power companies have had contractors cut back trees over power lines.  Some people get so mad about this tree cutting, yet are the first to complain about Facebook on their power being out.    Luckily Ida had minimum winds here, power loss would have been more widespread

[bluewave]

I just posted this paper a few days ago in the increase of 10” rainfall months in our area since around 2003 thread.

 

A recent study also found an abrupt shift to more extreme precipitation in the Northeast over this same time period.

https://journals.ametsoc.org/view/journals/hydr/18/6/jhm-d-16-0195_1.xml

Abstract

The northeastern United States has experienced a large increase in precipitation over recent decades. Annual and seasonal changes of total and extreme precipitation from station observations in the Northeast were assessed over multiple time periods spanning 1901–2014. Spatially averaged, both annual total and extreme precipitation across the Northeast increased significantly since 1901, with changepoints occurring in 2002 and 1996, respectively. Annual extreme precipitation experienced a larger increase than total precipitation; extreme precipitation from 1996 to 2014 is 53% higher than from 1901 to 1995. Spatially, coastal areas receive more total and extreme precipitation on average, but increases across the changepoints are distributed fairly uniformly across the domain. Increases in annual total precipitation across the 2002 changepoint are driven by significant total precipitation increases in fall and summer, while increases in annual extreme precipitation across the 1996 changepoint are driven by significant extreme precipitation increases in fall and spring. The ability of gridded observed and reanalysis precipitation data to reproduce station observations was also evaluated. Gridded observations perform well in reproducing averages and trends of annual and seasonal total precipitation, but extreme precipitation trends show significantly different spatial and domain-averaged trends than station data. The North American Regional Reanalysis generally underestimates annual and seasonal total and extreme precipitation means and trends relative to station observations, and also shows substantial differences in the spatial pattern of total and extreme precipitation trends within the Northeast.

1. Introduction

Multiple studies have found increasing total and extreme precipitation across the northeastern United States (Kunkel et al. 2013a; Peterson et al. 2013; Hayhoe et al. 2007), and extreme precipitation events have increased faster over the Northeast region than in any other part of the United States (Kunkel et al. 2013a). Hayhoe et al. (2007) found an increase of 10 mm decade⁻¹ in annual total precipitation from 1900 to 1999 using the 93 stations in the U.S. Historical Climatology Network in the states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, and Pennsylvania. Using the U.S. Climate Divisional Dataset, version 2, over the domain of Hayhoe et al. (2007) plus Maryland, Delaware, West Virginia, and Washington, D.C., Kunkel et al. (2013b) found a 10.2 mm decade⁻¹ increase in annual total precipitation over 1895–2011. However, across a similar time period (1901–2000) as Hayhoe et al. (2007), Walsh et al. (2014) and Kunkel et al. (2013b) found a trend of approximately 5.6 mm decade⁻¹.

Extreme precipitation events have also been increasing across the Northeast, both in intensity and frequency, particularly over the past three decades (Walsh et al. 2014; Kunkel et al. 2013a; Hoerling et al. 2016). This increase in extreme precipitation events is consistent with expected impacts of climate change on precipitation, primarily more extreme events driven by the ability of the atmosphere to hold more water as described by the Clausius–Clapeyron relationship (e.g., Trenberth 1998; Mishra et al. 2012; Prein et al. 2017). Kunkel et al. (2013a) found significant increases in both 2-day precipitation events that occur once every 5 years and the amount of precipitation falling on the 1% wettest days during the time period 1957–2010 for the Northeast. Hoerling et al. (2016) discovered a 2%–3% increase per decade in both the total amount and frequency of heavy precipitation events (5% wettest days) in the Northeast over 1901–2013, with the increases in heavy precipitation total amount, frequency, and intensity accelerating after 1979. Walsh et al. (2014) also evaluated trends in the amount of precipitation falling in the Northeast on the 1% wettest days using the Global Historical Climatology Network-Daily (GHCN-D) dataset, finding a striking increase of 71% from 1958 to 2012.

Given the growing consensus on the recent dramatic increase of extreme precipitation across the Northeast, our motivation is to explore the temporal and spatial attributes of precipitation increases in greater detail, as well as to assess the ability of gridded observational and reanalysis datasets to capture this precipitation increase. Specifically, we add to this literature by 1) assessing the sensitivity of total and extreme precipitation changes to the time period of analysis [sections 3a(1), 3a(3)]; 2) exploring the spatial distribution of total and extreme precipitation across the Northeast [sections 3a(2), 3a(4)]; 3) analyzing seasonal changes in total and extreme precipitation [section 3a(5)]; and 4) evaluating the consistency of means and trends in precipitation across station, gridded, and reanalysis data (section 3b).

4. Conclusions

Over the 1901–2014 station observational record in the Northeast, we find a significant 6.8% (0.6% decade⁻¹) increase in annual total precipitation and a much larger 41% (3.6% decade⁻¹) increase in annual extreme precipitation. However, a key conclusion of our study is that the recent increases in annual total and extreme precipitation in the Northeast are best characterized as abrupt shifts in 2002 and 1996, respectively, rather than long-term increases over several decades as could be implied from a linear trend. While the pre-changepoint trends in annual total (1901–2001; −1.6 mm decade⁻¹) and annual extreme (1901–95; 0.1 mm decade⁻¹) precipitation are not statistically significant, total precipitation from 2002 to 2014 was 13% higher than from 1901 to 2001 and extreme precipitation from 1996 to 2014 was 53% higher than from 1901 to 1995, with both increases being statistically significant. The fact that these wetter periods both abut the end of our record in 2014 means that any long-term linear trends are highly dependent on their start date and should therefore be interpreted with caution, particularly when extrapolating into the future. Of note, the recent 2015–16 drought in the Northeast is not included in our analyses, although it is not likely to change the significance of the post-changepoint increases.

Spatially, we find that the increases in annual total and extreme precipitation are widespread across the Northeast domain, with the exception of smaller increases and even some significant decreases to the east of Lake Erie, and in the southern part of the domain in West Virginia, Maryland, and Delaware. Our seasonal analysis reveals that fall and summer total precipitation have statistically significant increases after changepoints in 2002 and 2003, respectively, suggesting that they contribute to the annual total precipitation changepoint in 2002. The extreme precipitation increase across the 1996 changepoint is associated with 83% and 85% increases in spring and fall extreme precipitation, respectively, and may indicate common atmospheric forcing of spring and fall extreme precipitation in the mid- to late 1990s. The increase in fall precipitation across the 1995 changepoint is consistent with the finding of Kunkel et al. (2010) that increased heavy precipitation associated with tropical cyclones after 1994 is an important driver of the overall increase in extreme precipitation. Our ongoing investigations into the underlying dynamical causes for Northeast annual total and extreme precipitation increases are focusing on these critical time periods in the late 1990s and early 2000s.

Our comparison of spatial and temporal extreme precipitation patterns in station (GHCN-D), gridded (LI2013), and reanalysis (NARR) datasets shows that LI2013 is more consistent with station data than NARR. LI2013 reasonably captures the mean (within 2%) and seasonality (within 11%) of GHCN-D extreme precipitation, but contains significant differences in its trends. NARR underestimates regionally averaged extreme precipitation across all seasons by 1%–16%, and the annual extreme trends show significant differences in their spatial distribution, particularly over New England. Perhaps more importantly, both the NARR and LI2013 annual extreme time series have no significant changepoints.

LI2013 does, however, reproduce GHCN-D regionally averaged annual and seasonal total precipitation within 5% (and usually within 3%), and its trends faithfully capture those from station observations both across the region and averaged over the Northeast. In addition, LI2013 has a changepoint in 2003, only one year later than the changepoint identified in GHCN-D annual total precipitation. However, NARR underestimates annual and seasonal total precipitation by 3%–10% and has annual total precipitation trends that are a factor of 2–9 times smaller than GHCN-D trends. Spatially, NARR is also less accurate than LI2013, with decreasing 1979–2014 trends over much of the coastal and western portions of the domain where GHCN-D trends are positive. This comparison of LI2013 and NARR to GHCN-D provides important information on the strengths and limitations of these products for use in analyzing hydroclimate, forcing climate impacts models, and identifying drivers of total and extreme precipitation.

 

[Snowlover11]

death toll up to 25 in jersey with 6 people missing.

[gravitylover]

19 hours ago, user13 said:

There is a massive ecological problem. Water is very different from different parts of the country. Also, bacteria, algae, ect from long transport.

Knowing very little about this other than "the dream" I think that having UV "scrubbers" and other modern treatment and filtration stations at regular intervals throughout the system ought to solve this problem. 

11 hours ago, GrindOutWins said:

One question: Why does August and September of 2011 (?) get lost in the shuffle? I spent a ton of time driving all across orange, putnam, and westchester counties that late summer. There was another clear 5"+ rainfall over the entire northeast. Anyone remember this? 

edit: There was actually a huge rainstorm in October followed by "Snowtober" a week later (2011). I can't remember weather this wild since then but I definitely know that the entirely of that period I'm talking about didn't cause the level of devastation that this event just did. 

Irene, Lee and the snowstorm were devastating here. Power out for 5 days after Irene with over a quarter of the roads impassable from downed trees then an insane amount of frozen paste from the snowstorm that took the power out for another 7 days truly sucked. The media pretty much stopped talking about both the day after the initial event. Then again a year later when Sandy took out a few thousand trees followed by the pre Halloween foot and a half snowstorm left us without power for about 10 days. Oh and don't forget the March '18 snowstorm that knocked the power out for 8 days with temps in the teens and 20s. 

[tamarack]

13 hours ago, CoastalWx said:

If this occurred 40 miles NW, nobody would be talking like you are. It’s unfortunate it all came together over NY metro.

Unless it caused a "Brodhead Creek (1955)" event - 37 fatalities in NE PA.

[MJO812]

41 people dead in NY/ NJ and 7 missing

[qg_omega]

Deblasio trashing meteorologists for not predicting this, blaming it all on global warming

[IrishRob17]

40 minutes ago, tamarack said:

Unless it caused a "Brodhead Creek (1955)" event - 37 fatalities in NE PA.

According to this article the fatalities were even higher than that: https://www.poconorecord.com/article/20150818/news/150819477

[MJO812]