Central Park (CP) Does August rainfall equal or exceed 10" for a second successive month- first time since 1983 (it did 8/28 edit)? Closing date for your prediction 1159PM Aug 25

[wdrag]

Virtually all of us are aware of our wet July August.  CP is poised to exceed 10" of rainfall, for only the second time in its recorded history dating back to 1869.  Despite the controversy involved with the CP rainfall data of 1983, the two successive month record stands alone,  back to March-April 1983 and as Bluewave noted, EWR also exceeded.  I've not checked any Cooperative program data from that time, but there may be other supporting information for the CP data. 

What date, if any, do you expect CP to exceed 9.99" this August?  Closing date for your date prediction is 1159 PM Wednesday August 25. (no editing of your comment after calendar Aug 25)  What do you win?  NIX... except some back slaps from your American Weather friends.

I'll start the ball rolling:  Guessing will not exceed- certainly don't see this as a gimme, at least not yet (I can change my mind up to 1159PM tomorrow). So, this is an uncertain forecast-maybe not using the ensemble data to my best advantage but playing conservative, despite odds would say we should see normal 1 week qpf these last 7 days.  

Also,  I can move this topic elsewhere if you wish... I just thought it meshes well with the events that have just passed, and possibly ahead in September.

 

Added Bluewave post below... thank you for your work on this. 

 

The topic title was edited 8/28 in (parentheses) .

Th

[donsutherland1]

I hope it does, but my thinking is that it won’t reach or exceed 10”.

[wdrag]

31 minutes ago, donsutherland1 said:

I hope it does, but my thinking is that it won’t reach or exceed 10”.

We can still change thru 1159P Wednesday.  I think this sort of fits the recovery period that so often occurs after big events. NAEFS was conservative...seeming to be 1/4" thru 8/31.  However,  and there is always a however  :),  may need to monitor tropical moisture peeling nwd-newd-then end from Baha and coastal Texas toward us ~8/31.  Right now, I bank on that arriving just a little too late. 

[jm1220]

Thanks as always WDrag, but I’ll go with a no on this one as well. 

[uncle W]

so far Central Park has 9.65" and with seven days left I say yes...

[wdrag]

Maybe the odds are tilting toward a YES?  Depends in part what happens between Fri-Sun of this weekend (27-29).  Here's the new ensembled WPC outlook issued early this Wednesday morning.  

[LibertyBell]

12 hours ago, uncle W said:

so far Central Park has 9.65" and with seven days left I say yes...

How hard could it be to get 0.35" of rain?  Remember folks we have 7 days or a FULL WEEK to go.  It isn't that hard.  This ain't Tucson lol.

 

[Stormlover74]

The ever reliable gfs is a deluge for Friday night Saturday. Euro pretty wet as well so I'll go with yes

[LibertyBell]

1 hour ago, Stormlover74 said:

The ever reliable gfs is a deluge for Friday night Saturday. Euro pretty wet as well so I'll go with yes

Yeah I mean some of these people who are saying No must be thinking that August ends tomorrow lol.  SEVEN DAYS LEFT IN THE MONTH FOLKS!  It's almost impossible for it NOT to happen in our new climate.

 

[donsutherland1]

3 hours ago, LibertyBell said:

How hard could it be to get 0.35" of rain?  Remember folks we have 7 days or a FULL WEEK to go.  It isn't that hard.  This ain't Tucson lol.

 

Meanwhile, Tucson recorded 8.06” of rain in July.

[donsutherland1]

The 12z ECMWF is now wetter for Saturday. 

[doncat]

Had 11.13" in July... Have 8.71" this month.

[donsutherland1]

For reference, these are the locations at the highest latitude (eastern North America) that I could find that recorded one or more cases where July and August both received 10” or more of rain:

Norfolk (36.85N):

2004 July: 10.89”; August: 11.11”

2011 July: 10.89”; August: 10.79”

 

Salisbury, MD (38.36N):

2017 July: 11.31”; August: 12.23”

 

Wallops Island, VA (37.88N):

2004 July: 12.10”; August: 11.18”

 

Note: All of these cases occurred 2000 or later.

[Roger Smith]

I would say probably yes it does exceed 10" by about Saturday 28th as weak fronts stall and waves move along them, but as to amounts, could be anywhere from 1-4 inches, so may only just make it. 

Toronto has weather records going back to 1840 and the early 1840s had some very heavy rainfalls there, which are probably before most U.S. stations began their observing periods, although Caswell's Providence RI journal operated from 1831 to 1860. 

There were no examples of two months both hitting 10" or more at Toronto but in years from 1841 to 1843 there was enough rain at Toronto to suggest to me that it might be quite likely some U.S. locations which may have been in the path of tropical remnants that were part of these events may have reached totals that high. Rainfall was particularly excessive in late July and early August of 1841, and September of 1843. I found five or six week intervals that measured over 12" of rain in both cases. 

Looking now at Caswell's journal the highest two month total I found was 14.75" in July-Aug 1853. However his journal indicates that a rainfall on the night of July 12-13 1834 overflowed the capacity of his seven inch rain gauge and he isn't sure how much actually fell that night. Although his journal is admirable for general completeness and attention to detail, there are a few missing days and possibly missing precip on a few occasions, also it was interesting that when a hurricane hit the region on Oct 7, 1849, he details the events but never mentions the word hurricane (this is listed as a cat2-3 landfall that caused over a hundred deaths in s.e. MA -- the track looks like it went just barely to the east of Providence since he never got into tropical air and winds went strong NE to NW). 

If you don't already have this bookmarked, the journal can be seen in its entirety here: 

https://books.google.ca/books?id=oYY_AAAAcAAJ&pg=PA168&source=gbs_toc_r&cad=3#v=onepage&q&f=false

If that fails to load, look for the wikipedia entry for Alexis Caswell and then in the footnotes, the reference to his weather journal which was preserved by the Smithsonian Institute. Caswell is seen as one of the forerunners of development of late 19th century meteorological science in America. 

[wdrag]

Due to time constraints here at home... will hold NO, but completely understand trends are for more than .35".  I do know point specific qpf is exceedingly difficult to predict and that you can 1"/mi or greater gradients (MKE FF 1987),  so unless it's a well defined slow moving front or an area of low pressure passing along or just s of I80,  I get a little reluctant to express HIGH confidence. Seven days is a long time but we're now through day 1. Maybe we can end this tomorrow or Friday, but if we don't by Sunday night, then I think the uncertainty increases a bit.

 I as many others are rooting to accomplish the rarity of two successive 

I've attached CP August 2021.  First 9 days less than 0.35, and ditto 12-20.  So it does happen.  In this pattern, will it again?

[LibertyBell]

3 hours ago, donsutherland1 said:

For reference, these are the locations at the highest latitude (eastern North America) that I could find that recorded one or more cases where July and August both received 10” or more of rain:

Norfolk (36.85N):

2004 July: 10.89”; August: 11.11”

2011 July: 10.89”; August: 10.79”

 

Salisbury, MD (38.36N):

2017 July: 11.31”; August: 12.23”

 

Wallops Island, VA (37.88N):

2004 July: 12.10”; August: 11.18”

 

Note: All of these cases occurred 2000 or later.

Weird, would you say our climate is evolving to more of a coastal Virginia kind of climate?  I remember this brought up during the 2015-16 winter when JFK tied Norfolk as the only two locations that have had a 40 degree average winter temperature and 40 inches of snow.

 

[LibertyBell]

13 minutes ago, wdrag said:

Due to time constraints here at home... will hold NO, but completely understand trends are for more than .35".  I do know point specific qpf is exceedingly difficult to predict and that you can 1"/mi or greater gradients (MKE FF 1987),  so unless it's a well defined slow moving front or an area of low pressure passing along or just s of I80,  I get a little reluctant to express HIGH confidence. Seven days is a long time but we're now through day 1. Maybe we can end this tomorrow or Friday, but if we don't by Sunday night, then I think the uncertainty increases a bit.

 I as many others are rooting to accomplish the rarity of two successive 

I've attached CP August 2021.  First 9 days less than 0.35, and ditto 12-20.  So it does happen.  In this pattern, will it again?

Walt I see our major media outlets predicting exactly that, a stalled front over our region and a developing low delivering flooding rains across NJ and NY on Saturday.

 

 

[donsutherland1]

57 minutes ago, LibertyBell said:

Weird, would you say our climate is evolving to more of a coastal Virginia kind of climate?  I remember this brought up during the 2015-16 winter when JFK tied Norfolk as the only two locations that have had a 40 degree average winter temperature and 40 inches of snow.

 

It is. One study suggested that NYC’s climate could resemble that of present-day Virginia Beach by the end of the 21st century.

[donsutherland1]

At present, I still lean toward a miss. Hopefully, that thinking is incorrect.

Currently, 23/51 (45%) of EPS members (8/25 12z) show 0.35” or more. That is broadly in line with the historical frequency for the 1971-2020 period. As tomorrow is virtually certain to see no rain, I ran the numbers of the 8/27-8/31 period. 60% of cases had < 0.35” rain. 40% had 0.35” or more (20% had 1.00” or more). 

The National Blend of Models still does not show enough precipitation. 

[LibertyBell]

33 minutes ago, donsutherland1 said:

It is. One study suggested that NYC’s climate could resemble that of present-day Virginia Beach by the end of the 21st century.

If that was year round that would mean we could still get a big winter (like they had in 1965-66 and 2009-10)  but it would probably be a once in 30 year occurrence.  Many more 90 degree days and perhaps a 100 degree high every year on average.  Also scary to think about getting a TC hit up here likely every other year.

 

[Stormlover74]

Nam is a good soaking Friday night and Saturday 

[wdrag]

Good Thursday morning,  WPC has almost 1.5" NYC by the end of the month.  SPC HREF tries for Friday.  HRRR is not optimistic through 06z/Sat.  Other 00z/26 models including UK/EC struggle to get to 1/4".  I didn't check ens but am sure they're over the .35" limit.  From an EC K index perspective,  it's more or less we get it late today or we have to get late Sunday or Monday.  The probably soon to be named Caribbean-GMEX TC influence arrives too late for August.   Let's see how this evolves. 513A/26

[wdrag]

0.08 so far today at CP ending 20z/27.  that raises the monthly total to 9.73 and only 0.27" more by Sept 1 too exceed 10".  Aint lookin good for the NO's  like myself on this one.

[donsutherland1]

With 0.66” of rain so far, Central Park has reached 10” rain for August.

[LibertyBell]

6 minutes ago, donsutherland1 said:

With 0.66” of rain so far, Central Park has reached 10” rain for August.

1983 is always going to be special to me because of how amazingly hot it was wall to wall, and even at JFK.  The funny thing about it being the rainiest year on record is it didn't rain all that much during the summer, which was perfectly timed and enabled it to be super hot.

 

[wdrag]

So all who had it as a gimme and or 1-4" etc...you're winners.  I'll check some more data tomorrow.  So, what this means to me... we've had a unique two consecutive months in our NYC CP history,  seldom seldom recording two 10+'s in a row.  Can our two month total exceed 1983's two consecutive months (see top of thread) 24.55"?  Need 3.16" or thereabouts.  Finally,  long-long-long shot, but might we try for a third totally unique 3 consecutive months.  Seems like we have to get a dose of IDA (RRQ of se Canada trough and inflow at 850 from IDA).  That could be in the 3-6" range... (or miss us?).  I may be starting a NORA contribution thread tomorrow, as I'm pretty sure RH is going to come out of Baha and cross the Rockies and join an approaching CF here ~ the 5ht or so.  Then after the 7th??? There may be more?  Repeating trough looks okay to our west if we get some more TC up w of 80W Longitude. 

 

 

[donsutherland1]

17 minutes ago, wdrag said:

So all who had it as a gimme and or 1-4" etc...you're winners.  I'll check some more data tomorrow.  So, what this means to me... we've had a unique two consecutive months in our NYC CP history,  seldom seldom recording two 10+'s in a row.  Can our two month total exceed 1983's two consecutive months (see top of thread) 24.55"?  Need 3.16" or thereabouts.  Finally,  long-long-long shot, but might we try for a third totally unique 3 consecutive months.  Seems like we have to get a dose of IDA (RRQ of se Canada trough and inflow at 850 from IDA).  That could be in the 3-6" range... (or miss us?).  I may be starting a NORA contribution thread tomorrow, as I'm pretty sure RH is going to come out of Baha and cross the Rockies and join an approaching CF here ~ the 5ht or so.  Then after the 7th??? There may be more?  Repeating trough looks okay to our west if we get some more TC up w of 80W Longitude. 

 

 

It will also be interesting to see how Tucson does with Nora’s moisture. July was its wettest month on record.

[LibertyBell]

4 hours ago, donsutherland1 said:

It will also be interesting to see how Tucson does with Nora’s moisture. July was its wettest month on record.

Has a TC ever made landfall in SoCal or Arizona?  I want to see a storm go right up the Gulf of California without hitting land until it hits the US border.  I wonder if a hurricane could maintain its intensity doing that?

 

[donsutherland1]

7 hours ago, LibertyBell said:

Has a TC ever made landfall in SoCal or Arizona?  I want to see a storm go right up the Gulf of California without hitting land until it hits the US border.  I wonder if a hurricane could maintain its intensity doing that?

 

In 1858, a hurricane impacted San Diego. Here’s a paper on that storm, which mentions others that have impacted CA and/or AZ:

https://www.aoml.noaa.gov/hrd/Landsea/chenowethlandsea.pdf

 

[wdrag]

August CP total 10.32 through 8AM/28.  Just so you know how difficult it is... Newark T past 24 hours, so far.  So, I know some want to state it was a gimme...  but not in my mind.  Convective qpf has very large gradients over just a 1000-5000 feet.  Now, how much more  before Sept 1?  Please see IDA thread. 

 

I've added digital storm total data for this event through 606AM,  and note the black areas of no qpf up against the rainy areas. To illustrate further, at 922AM I added the CoCoRAHS data...note in NNJ the 1.61" and the Trace very nearby. Click CoCoRaHs map for greater clarity.