September 2021

[LibertyBell]

13 hours ago, bluewave said:

This may be the furthest north along the East Coast that a post tropical or tropical cyclone has spawned an EF-3 tornado.

what caused those crazy EF4 in CT and MA though? I find it weird that they can occur so far north and yet we haven't seen them in NY or NJ

 

[CIK62]

The next 8 days are averaging 76degs.(68/85), or +6.

Month to date is  70.5[-2.5].        Could be  73.4[+1.6] by the 16th.

Just 0.3" tonight/tomorrow..    CMC has 0.8".   SREF has 0.7".    GFS T's return to Normal in about 10 days now. 

Reached 79 here yesterday.

70*(82%RH), hazy blue.    72* at 9am.        Spent Noon-5pm period at 75*---77* with a nasty S wind, but decent sun.

[donsutherland1]

Morning thoughts…

Overnight, the model consensus for rainfall from tonight through tomorrow has increased. A widespread 0.50”-1.50” now appears likely with locally higher amounts. The EPS mean now shows 1” in New York City with 43% of members showing 1” or more. The NBE is now up to just over 0.50”. 

Today will be partly sunny and warm. Clouds will increase later in the day with showers and thunderstorms arriving. High temperatures will likely reach the lower and middle 80s in most of the region.  Likely high temperatures around the region include:

New York City (Central Park): 81°

Newark: 86°

Philadelphia: 85°

Normals:

New York City: 30-Year: 79.0°; 15-Year: 79.0°

Newark: 30-Year: 80.5°; 15-Year: 80.8°

Philadelphia: 30-Year: 81.6°; 15-Year: 81.8°

Tomorrow will be mostly cloudy with some additional rain.

[bluewave]

12 hours ago, wdrag said:

A problem last Wednesday; NIGHT time... much more difficult to judge-assess, especially in near panic mode of torrential rain and some lightning.  Also, I think the upgraded warnings were not NEW issuance but prior warning updates (I will stand corrected if I'm wrong but IEM COW did not show new warnings for me); TRAPPED???  EMERGENCY warnings almost too late as torrents were surcharging manhole-sewer systems and people were getting stuck, abandoning vehicles. Finally for me: how much practice do we get warning the EXTREME RECORD breaking event?  Experience breeds confidence.  WARNING the EXTREME in real time made me almost always pause and be more conservative because it was so seldom in my lifetime. 

Yeah, that gets to prior experience  and normalcy bias which are discussed in the article below.

https://theconversation.com/why-do-people-try-to-drive-through-floodwater-or-leave-it-too-late-to-flee-psychology-offers-some-answers-157577

While playing in or driving through flood waters are avoidable risks, the latter involve adults who generally know the risks – much to the frustration of emergency authorities. So what convinces people make risky decisions in a flood? 

Drivers in our study reported that they saw a majority of people in other vehicles (about 64%) driving through the floodwater, while only 2% were turning around. 

Seeing others do something often leaves people with the impression this behaviour is typical and relatively safe, an effect known as “normalcy bias”.

In 15% of cases we studied, passengers also put pressure on drivers to cross.

When things go wrong, they can go very wrong

Another key reason involves prior experience and perceived probability of adverse outcomes. While 9% reported a negative outcome (such damage to their car or having to be rescued), 91% reported proceeding without any incident. 

The reasons for these crossings were not sudden or impulsive, but often involved what the person saw as “careful consideration” of everyday needs — such as the need to get to work or buy groceries. 

This presents an obvious challenge for emergency authorities. While most people succeed without issues, the cases where something goes wrong can be catastrophic and in some cases fatal.

So, how do we convey the very real risks of floodwater? How do we highlight the need for people to prepare an evacuation plan and avoid entering floodwater?

 

 

 

[wdrag]

On 9/7/2021 at 8:32 AM, bluewave said:

These great tweets from the NWS Mt Holly highlight how extreme our weather has become.

 

This may be a little disconcerting to read-hear, but having worked there and other offices. LSR's are dependent in large part on population density combined with SEEKING reports and of course the reports that are received by phone, spotter reporting. The goal when I worked was to verify warnings and do a lot of post event calling, reading newspaper accounts, and in todays day,  seeking reports via social media. MPing can also contribute reports.  Therefore, other states are lower, in part due to processes of acquiring reports, population density and I think, priorities - available staff. 

This data probably should have been normalized by population.  I see no other way to further normalize this data.

Yes, working the I95 corridor DCA-BOS is I think a larger than normal YEAR ROUND responsibility due to population-impacts on commerce, and also the broader array of weather events that impact this region. For NJ, it can range from killer fire weather, to hurricanes,  coastal flooding, severe storms, flooding, dense fog,  urban heat warnings, freezing spray, ice jams, synoptic scale wind, and last but not least-heavy snow-blizzards.  Not every state has this array of events (let's not forget tsunami).  So the responsibility, imo, is greater here in the I95 corridor but I do think this data needed to be normalized.  The data is out there now as a news story, but I do wish there would be a greater attempt at perspective, as I feel the same on all other events that we watch-warning for. 

[bluewave]

44 minutes ago, wdrag said:

This may be a little disconcerting to read-hear, but having worked there and other offices. LSR's are dependent in large part on population density combined with SEEKING reports and of course the reports that are received by phone, spotter reporting. The goal when I worked was to verify warnings and do a lot of post event calling, reading newspaper accounts, and in todays day,  seeking reports via social media. MPing can also contribute reports.  Therefore, other states are lower, in part due to processes of acquiring reports, population density and I think, priorities - available staff. 

This data probably should have been normalized by population.  I see no other way to further normalize this data.

Yes, working the I95 corridor DCA-BOS is I think a larger than normal YEAR ROUND responsibility due to population-impacts on commerce, and also the broader array of weather events that impact this region. For NJ, it can range from killer fire weather, to hurricanes,  coastal flooding, severe storms, flooding, dense fog,  urban heat warnings, freezing spray, ice jams, synoptic scale wind, and last but not least-heavy snow-blizzards.  Not every state has this array of events (let's not forget tsunami).  So the responsibility, imo, is greater here in the I95 corridor but I do think this data needed to be normalized.  The data is out there now as a news story, but I do wish there would be a greater attempt at perspective, as I feel the same on all other events that we watch-warning for. 

A recent paper used the STP to increase confidence in the reports of tornadoes shifting east from the Plains.

https://www.nature.com/articles/s41612-018-0048-2

Meanwhile, a robust upward trend is found in portions of the Southeast, Midwest, and Northeast (Fig. 4). No significant increase (decrease) in tornado environments is observed west (east) of the 95^th meridian. We believe these trends in tornado environments are significant and have not been documented with this level of detail by previous research.

https://www.sciencedaily.com/releases/2018/10/181017172846.htm

The researchers tracked the number of tornado reports from 1979 to 2017, while also investigating regional trends in the daily frequency of tornado-environment formation over the same time period, using an index known as the Significant Tornado Parameter (STP). Frequently used for predicting severe weather, the index captures the coexistence of atmospheric ingredients favorable for producing tornadoes.

Both the number of actual tornado reports and the historical STP analysis showed the eastward uptick in tornado frequency.

"One could argue that because a region's population has increased, more tornadoes are sighted and reported," Gensini said. "But we also identified this eastward trend when using the STP index, which looks at the frequency of tornado environments and has nothing to do with people. This increases our confidence in the reporting trend that we're seeing."

The trend is important for understanding the potential for future tornado exposure, damage and casualties. Severe thunderstorms accompanied by tornadoes, hail and damaging winds cause an average of $5.4 billion of damage each year across the United States, and events with $10 billion or more in damages are no longer uncommon.

 

[wdrag]

14 minutes ago, bluewave said:

A recent paper used the STP to increase confidence in the reports of tornadoes shifting east from the Plains.

https://www.nature.com/articles/s41612-018-0048-2

Meanwhile, a robust upward trend is found in portions of the Southeast, Midwest, and Northeast (Fig. 4). No significant increase (decrease) in tornado environments is observed west (east) of the 95^th meridian. We believe these trends in tornado environments are significant and have not been documented with this level of detail by previous research.

https://www.sciencedaily.com/releases/2018/10/181017172846.htm

The researchers tracked the number of tornado reports from 1979 to 2017, while also investigating regional trends in the daily frequency of tornado-environment formation over the same time period, using an index known as the Significant Tornado Parameter (STP). Frequently used for predicting severe weather, the index captures the coexistence of atmospheric ingredients favorable for producing tornadoes.

Both the number of actual tornado reports and the historical STP analysis showed the eastward uptick in tornado frequency.

"One could argue that because a region's population has increased, more tornadoes are sighted and reported," Gensini said. "But we also identified this eastward trend when using the STP index, which looks at the frequency of tornado environments and has nothing to do with people. This increases our confidence in the reporting trend that we're seeing."

The trend is important for understanding the potential for future tornado exposure, damage and casualties. Severe thunderstorms accompanied by tornadoes, hail and damaging winds cause an average of $5.4 billion of damage each year across the United States, and events with $10 billion or more in damages are no longer uncommon.

 

did read this prior to post.

I still believe I'm correct we have report seek/population bias. # of LSR reports can include hail, ice, snowfall of 1"/hr or greater, storm totals.  Eastward trend of TOR environment is understood.  Also, having worked 1980s-90's, we just didn't have as much human kind dedication (EM's and spotter coordinators I think are now trained to do some of this for the NWS) to finding every little TOR, or  time to do the job correctly.  

I did read NSW article.  Good information.  

 

[LoboLeader1]

Currently 75* here, RH 68/DP 64

[Brian5671]

21 minutes ago, Torch said:

Off topic a bit: Louis  Uccellini retiring. Sorry if discussed already.

saw that elsewhere-one of the all time greats!

[wdrag]

Sept: last half seems to be setting up ever-so-slowly for plenty of rain here.  Ridging developing northern tier, while a weakness evolves Gulf States (wet).  

I see NYC yesterday only a NORMAL day.   Might happen again Friday-Sat, but otherwise me it looks like the warmer than normal pattern here should continue through at least the 23rd. 

[bluewave]

Dew points back above 70° here on the South Shore. So it’s no surprise that more heavy rain is in the forecast around the region. A continuation of the high humidity theme. Ben Noll posted an expanded version of this for the entire Northeast. I posted the local NYC Metro records of recent years earlier in the thread.

Wantagh          N/A     77  72  83 S8    

 

[gravitylover]

12 hours ago, LibertyBell said:

the only way to do it is to just shut the roads down so people cant travel, that will take the decision making process out of their hands.

We see how well that works during blizzards. I think the bottom line is NWS issues watches and warnings and people being people will then go on to make their decisions based on their needs at the moment. Even knowing better I've made some questionable decisions over the years when it comes to moving water over roadways when turning around wasn't a better option or the end goal was important.

[Dark Star]

1 hour ago, wdrag said:

did read this prior to post.

I still believe I'm correct we have report seek/population bias. # of LSR reports can include hail, ice, snowfall of 1"/hr or greater, storm totals.  Eastward trend of TOR environment is understood.  Also, having worked 1980s-90's, we just didn't have as much human kind dedication (EM's and spotter coordinators I think are now trained to do some of this for the NWS) to finding every little TOR, or  time to do the job correctly.  

I did read NSW article.  Good information.  

 

I think case in point is that the tornado damage occurred in Mullica Hill, in which appears to be a new development?  The many undeveloped areas in the most densely populated state are disappearing.  AS my brother in law says: K Hovnanian - Filling the spaces in between the spaces.   The forecast last Wednesday was correct.  However, the actual real time radar was showing the main area of precipitation missing the most populated areas to the north, the radar filled in the back trailing end just before it hit NE New Jersey.  I was dead wrong (this wasn't the first time)...

[LibertyBell]

2 hours ago, gravitylover said:

We see how well that works during blizzards. I think the bottom line is NWS issues watchings and warning and people being people will then go on to make their decisions based on their needs at the moment. Even knowing better I've made some questionable decisions over the years when it comes to moving water over roadways when turning around wasn't a better option or the end goal was important.

We saw this during Harvey too.  Sometimes there is no other option.

I'd like to know what have been the costliest disasters in NYC tristate area, both in terms of dollars and lives?  Sandy and Ida must both be near the top of the list, but what about long duration events like the December 1992 noreaster?  I remember the area was basically underwater during that historic event.  Blizzard of 1888 is right up there too.

 

[LibertyBell]

2 hours ago, Dark Star said:

I think case in point is that the tornado damage occurred in Mullica Hill, in which appears to be a new development?  The many undeveloped areas in the most densely populated state are disappearing.  AS my brother in law says: K Hovnanian - Filling the spaces in between the spaces.   The forecast last Wednesday was correct.  However, the actual real time radar was showing the main area of precipitation missing the most populated areas to the north, the radar filled in the back trailing end just before it hit NE New Jersey.  I was dead wrong (this wasn't the first time)...

There's good reasons to keep them undeveloped....both for environment's sake and for human lives.

 

[LibertyBell]

3 hours ago, wdrag said:

Sept: last half seems to be setting up ever-so-slowly for plenty of rain here.  Ridging developing northern tier, while a weakness evolves Gulf States (wet).  

I see NYC yesterday only a NORMAL day.   Might happen again Friday-Sat, but otherwise me it looks like the warmer than normal pattern here should continue through at least the 23rd. 

but probably no more 90s at least not here.

 

[LibertyBell]

2 hours ago, bluewave said:

Dew points back above 70° here on the South Shore. So it’s no surprise that more heavy rain is in the forecast around the region. A continuation of the high humidity theme. Ben Noll posted an expanded version of this for the entire Northeast. I posted the local NYC Metro records of recent years earlier in the thread.

Wantagh          N/A     77  72  83 S8    

 

Second  most?  Is 2016 number 1 with the 42 75+ dew point days at JFK?

 

[JerseyWx]

13 hours ago, LibertyBell said:

the only way to do it is to just shut the roads down so people cant travel, that will take the decision making process out of their hands.

And then you have to stop every vehicle to see who's essential and who isn't?  NWS puts out the warnings, it's up to the public to read and interpret them.

[LibertyBell]

30 minutes ago, JerseyWx said:

And then you have to stop every vehicle to see who's essential and who isn't?  NWS puts out the warnings, it's up to the public to read and interpret them.

But that's essentially what we did in Sandy.  That's what they are planning to roll out for Flash Flood Emergencies too.

 

[LibertyBell]

Where did this horrible wind come from? I didn't see anyone say prepare for windy conditions.  It took my power out!

 

[Dan76]

1 hour ago, LibertyBell said:

Where did this horrible wind come from? I didn't see anyone say prepare for windy conditions.  It took my power out!

 

NWS had it in their forecast since monday.

[LibertyBell]

1 minute ago, Dan76 said:

NWS had it in their forecast since monday.

Yeah but bad enough to create a power outage?  I don't usually take 20-25 mph gusts too seriously.....we usually need 40 mph sustained winds or 60 mph gusts to cause a power outage here.

[Dan76]

5 minutes ago, LibertyBell said:

Yeah but bad enough to create a power outage?  I don't usually take 20-25 mph gusts too seriously.....we usually need 40 mph sustained winds or 60 mph gusts to cause a power outage here.

Welcome to PSE&G

[LibertyBell]

7 minutes ago, Dan76 said:

Welcome to PSE&G

Imagine if we had gotten the 8-14" of rain that NJ and NYC got with Ida....wow.....it would be like Sandy conditions on Long Island with power outages and long gas lines.

 

[Gravity Wave]

10 hours ago, bluewave said:

A recent paper used the STP to increase confidence in the reports of tornadoes shifting east from the Plains.

https://www.nature.com/articles/s41612-018-0048-2

Meanwhile, a robust upward trend is found in portions of the Southeast, Midwest, and Northeast (Fig. 4). No significant increase (decrease) in tornado environments is observed west (east) of the 95^th meridian. We believe these trends in tornado environments are significant and have not been documented with this level of detail by previous research.

https://www.sciencedaily.com/releases/2018/10/181017172846.htm

The researchers tracked the number of tornado reports from 1979 to 2017, while also investigating regional trends in the daily frequency of tornado-environment formation over the same time period, using an index known as the Significant Tornado Parameter (STP). Frequently used for predicting severe weather, the index captures the coexistence of atmospheric ingredients favorable for producing tornadoes.

Both the number of actual tornado reports and the historical STP analysis showed the eastward uptick in tornado frequency.

"One could argue that because a region's population has increased, more tornadoes are sighted and reported," Gensini said. "But we also identified this eastward trend when using the STP index, which looks at the frequency of tornado environments and has nothing to do with people. This increases our confidence in the reporting trend that we're seeing."

The trend is important for understanding the potential for future tornado exposure, damage and casualties. Severe thunderstorms accompanied by tornadoes, hail and damaging winds cause an average of $5.4 billion of damage each year across the United States, and events with $10 billion or more in damages are no longer uncommon.

 

This is interesting. Has there been any research on tornado conditions in the Great Plains (i.e. the classic 'Tornado Alley')? That study indicates that the plains have been experiencing fewer tornadoes relative to the South and Midwest but nothing about the raw numbers of tornadoes in that region. This obviously isn't scientific but growing up almost every major outbreak seemed to be in the plains and over the past decade it feels like there's been more diversity in terms of tornado distribution. If there are fewer tornadoes in the Plains, what are some possible explanations? 

 

[GrindOutWins]

Severe Thunderstorm Watch

SEVERE THUNDERSTORM WATCH OUTLINE UPDATE FOR WS 491
NWS STORM PREDICTION CENTER NORMAN OK
755 PM EDT WED SEP 8 2021

SEVERE THUNDERSTORM WATCH 491 IS IN EFFECT UNTIL 1200 AM EDT
FOR THE FOLLOWING LOCATIONS

NYC021-027-039-071-079-087-105-111-090400-
/O.NEW.KWNS.SV.A.0491.210908T2355Z-210909T0400Z/

NY
.    NEW YORK COUNTIES INCLUDED ARE

COLUMBIA             DUTCHESS            GREENE
ORANGE               PUTNAM              ROCKLAND
SULLIVAN             ULSTER
$$

...a very hot and humid September night out there currently. You can smell the moisture in the air. Should be interesting to see what happens when the line develops. 

[donsutherland1]

A cold front will cross the region tonight. In doing so, it will bring showers and thunderstorms to parts of the region. Afterward, the front's progression will slow and there is a possibility that parts of the region will see additional rainfall tomorrow. In general, most of the region will likely see 0.50"-1.50" of rain. Some areas, especially northwestern New Jersey and northeastern Pennsylvania could see 2"-3" rainfall amounts. 2"-3" rainfall amounts could also develop across eastern New England.

A warming trend will likely develop this weekend. Despite a cooler than normal first 7-10 days, September will likely feature near normal to somewhat warmer than normal temperatures in much of the region. The second half of the month could feature above to perhaps much above normal temperatures.

Fall 2021 will likely be wetter to much wetter than normal in the northern Middle Atlantic region. Since 1869, there have been 9 August cases where New York City picked up 20.00" or more rainfall during the summer. Two thirds of those cases (and 4/5 of those with summer mean temperatures of 73.0° or above) had 17.00" or more fall precipitation in New York City. 2011 is probably the closest match in terms of precipitation and a nearly identical summer mean temperature. Mean fall precipitation for those 9 cases was 14.86". The median was 17.35". The 1991-2020 normal value is 12.27".

The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.3°C for the week centered around September 1. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.22°C and the ENSO Region 3.4 anomaly has averaged -0.43°C. Neutral ENSO conditions will likely prevail through September. Afterward, La Niña conditions could begin to develop.

The SOI was +3.63 today.

The preliminary Arctic Oscillation (AO) figure was -0.417 today.

On September 6 the MJO was in Phase 4 at an amplitude of 1.097 (RMM). The September 5-adjusted amplitude was 0.914 (RMM).

Based on sensitivity analysis applied to the latest guidance, there is an implied 61% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 70.1° (0.9° above normal).

 

[Santa Claus]

78/68 at 8:20 PM on September 8th.  i'm really just numb to humidity at this point, this feels perfectly comfortable especially with the wind.

i'd like to understand the physiological responses to constant exposure to heat and humidity.  there must be long-term adjustments the body makes if you move to different climates.  probably centered around hormonal changes and metabolic adjustments but probably too electrolyte and water management, skin secretions, hair growth, who knows.

[RippleEffect]

How bad is this weather going to get tonight into tomorrow?

[Cfa]

13 hours ago, gravitylover said:

We see how well that works during blizzards. I think the bottom line is NWS issues watches and warnings and people being people will then go on to make their decisions based on their needs at the moment. Even knowing better I've made some questionable decisions over the years when it comes to moving water over roadways when turning around wasn't a better option or the end goal was important.

And even with watches/warnings some people simply don’t get the message. Even as a weather enthusiast, the March 2010 Nor’easter caught me completely off guard, I’d known nothing about it at all, it was simply a normal day, until it wasn’t. We were in Garden State Plaza all day and stepped outside into what resembled a landfalling Hurricane, just minutes before the mall lost power.

Being on the GWB during all of this, as it was closing, is still my #1 wildest/scariest weather moment, the wind gusts were literally lifting up the front of our vehicle, and MOVING it, in the outer lane, in heavy traffic. Those gusts had to be well in excess of 100mph, I don’t know how they kept that bridge open for as long as they did.