Jump to content
  • Member Statistics

    17,610
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

Sun July 11-Mon July 19 Pockets of FF/SVR and a modest heat wave


wdrag
 Share

Recommended Posts

Yep,

I did not expect this in Monmouth this eve (from morning post)...  it seems to be mostly FF,  with spotty microburst damage.  At least something happened near NYC.  Good WXunderground post by DONCAT. Thanks!

 

The remainder of the eve...N CT primary but keep monitoring other cells still warned.

 

Added the first 13 days of July from CoCoRAHS only.    AND the lightning that occurred late yesterday into predawn today,

 

Presuming this weekend's heavy showers occur, we may start a month long normal or below normal rainfall trend sometime next week...into mid August, per CPC only. 

 

Click on the maps and they show more clearly. 

Screen Shot 2021-07-14 at 5.45.25 PM.png

Screen Shot 2021-07-14 at 5.46.17 PM.png

 

Screen Shot 2021-07-14 at 6.23.38 AM.png

  • Like 1
Link to comment
Share on other sites

545A Thursday: Extended the original 9th post headline to Monday July 19.  

Modest heatwave at least for portions of NJ through Sat continues. Peak of the Heat Index values 95-100F either Fri or Sat?

The main reason to extend the duration is for QPF purposes. Appears to me that a short wave (weak closed LOW aloft) will separate and drift east across the mid Atlantic states Sunday-Monday, hanging up the front a bit with HIGH PW (nr 2") airmass  near and south of the front Sunday and possibly into Monday in our NYC subforum.  IF that occurs, heavy qpf would occur along and south of the boundary, certainly into Sunday and possibly Monday. Where all this qpf will occur??  

Guessing Sat I80 northward, Sunday I80 southward, but that is just an idea.  Yes, there is still a chance the front will drift south of us faster, limiting the risk to Sat only, but there just seems to be too much information indicating caution on the previously faster progression.

In the meantime: Today- could be a late shower or Tstm in high PW air coastal NJ?

FrI: No SPC marginal risk for SVR, and wind fields are not favoring but with the approaching CF, I think the I90 to I84 corridor is at risk for isolated embedded SVR late Fri-Fri eve.

Sat: Think it likely for FF and wetmicrobust wind damage thunderstorms, especially I80 north later in the day eve. No SPC outlook but there is from WPC, please see attached. It's a broad outlook but well stated. 

Sun-Mon: TBD per pgh's above.

alid 12Z Sat Jul 17 2021 - 12Z Sun Jul 18 2021

...THERE IS A SLIGHT RISK FOR EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST...

...Tennessee River Valley to southern New England...
A very slow moving cold front with multiple waves of low pressure
along it is forecast to be in place from the Ohio Valley to New
England on Saturday morning, and a strong upper ridge/Bermuda high
will limit the eastward progression of this front through early
Sunday.  Much of the interior Northeast will be under the right
entrance region of the upper level jet, along with an incoming 500
mb shortwave trough.  At the surface, PWs are expected to surge
near or slightly above 2 inches from the eastern Mid-Atlantic to
southern England, which is well above the 90th percentile for this
region.  A corridor of enhanced PWs should along exist farther
southwest ahead of the front from Tennessee to the central
Appalachians, along with plenty of instability with surface based
CAPE near 2000 J/kg. 

These factors will be enough to produce widespread moderate to
intense convection with high rainfall rates, with the model
consensus suggesting the potential for widespread 1-3 inch
rainfall totals from central Pennsylvania to the Massachusetts
close where the Slight Risk area resides.  It is also important to
note that portions of this region have significantly reduced flash
flood guidance owing to 300-500% of normal 7-day rainfall over the
past week, and those areas will be more vulnerable to flash
flooding from slow moving storms.

 

Screen Shot 2021-07-15 at 5.16.36 AM.png

 

  • Like 3
Link to comment
Share on other sites

6 hours ago, gravitylover said:

Hey @wdrag I know you have some New England experience :) so... Do you think this makes it to the RI coast as strong as it could be here? We have a two day outdoor festival that we've paid for the booth space and it's rain or shine so I need to know how to prepare. Thanks ;) 

Cannot quote me:  Decision time for you is when?    

 

tonights 00z HPC HREF is a start into what and where Sat.  I think we're looking good here for big QPF.  my guess is RI is targeted Sunday but i could completely wrong.  Still uncertainty...  

Let me know decision time. Thanks,

 

Link to comment
Share on other sites

No changes in outlook.  Sun-Mon remain up in the air.  CF and weak low pressure posit combined with PWAT bullseye will determine deluge areas of concern. NAVGEM suddenly on board with EC for Sun-Mon.

I think its good to remember all the modeling has been off on for Sunday so all i'm pretty sure of is an active Sat afternoon-night I80 north. 

BTW 3rd 90F day of the week at KEWR and other locations NNJ, 2 in a row there and many other spots NJ except NW NJ high terrain and some of the coasts.  HI Near 100F HI tomorrow and then Sat has all to do with posit of the CF...going to be close for a 90F day in NNJ.  s NJ looks like HI near 100... boundary somewhere between I84-I80?

SPC moved the Marg risk tomorrow closer into the nw part of the subforum.  I think a good move. 

Have a good night. 

Walt

  • Thanks 1
Link to comment
Share on other sites

11 hours ago, wdrag said:

Cannot quote me:  Decision time for you is when?    

 

tonights 00z HPC HREF is a start into what and where Sat.  I think we're looking good here for big QPF.  my guess is RI is targeted Sunday but i could completely wrong.  Still uncertainty...  

Let me know decision time. Thanks,

 

Appears to me a possible  tstm RI very late this afternoon-eve; better chance sometime later Sat night, and to me, best chance for heavy storms is Sunday up there in RI.  Let me know how it goes. Thanks.  Walt

Link to comment
Share on other sites

No changes for me:  Sunday-early Monday are in doubt due to model differences, the Canadian a little exuberant for our area while the GFS/EC say the potential big show is basically done by dawn Sunday. 

Therefore, focusing these next two days: SPC marginal risk both today-tomorrow in our subforum due to greatest instability.  Stronger wind tomorrow so I suspect more widespread outbreak Saturday.  However, can't rule out a damaging tstm I84 corridor to near- just north of NYC late today.  

Pattern suggests to me isolated 4 to 5" by daybreak Sunday. Where best chance?  

Cant comment further right now...may be back late today.  Have a good day.

 

 

 

  • Like 1
Link to comment
Share on other sites

4 hours ago, wdrag said:

No changes for me:  Sunday-early Monday are in doubt due to model differences, the Canadian a little exuberant for our area while the GFS/EC say the potential big show is basically done by dawn Sunday. 

Therefore, focusing these next two days: SPC marginal risk both today-tomorrow in our subforum due to greatest instability.  Stronger wind tomorrow so I suspect more widespread outbreak Saturday.  However, can't rule out a damaging tstm I84 corridor to near- just north of NYC late today.  

Pattern suggests to me isolated 4 to 5" by daybreak Sunday. Where best chance?  

Cant comment further right now...may be back late today.  Have a good day.

 

 

 

BGM at least believes Catskills/Poconos will be a big target tomorrow within their CWA so I would think most other places that can get into warm sector 

Link to comment
Share on other sites

14 minutes ago, bluewave said:

The HREF has another strong flash flooding and severe signal. But it will probably take a few more runs to pin down the exact locations. It has done very well with these general signals recently. 
 

2FDB5CD9-3A6B-4753-907E-98DA33322219.thumb.jpeg.ef6798b81397fbde54c44196c277f1c9.jpeg

Wow NE NJ/NYC metro look to be a hotspot again if that is correct.

Link to comment
Share on other sites

1 hour ago, bluewave said:

The HREF has another strong flash flooding and severe signal. But it will probably take a few more runs to pin down the exact locations. It has done very well with these general signals recently. 
 

2FDB5CD9-3A6B-4753-907E-98DA33322219.thumb.jpeg.ef6798b81397fbde54c44196c277f1c9.jpeg

I think this is overdone, this is mostly a 1 inch event!

  • Weenie 2
Link to comment
Share on other sites

think it's a good idea to be ready for some short duration FF this eve in nw NJ and parts of our area Sat afternoon-eve.  

It should end by sunrise Sunday and this airmass should dry out per modeling.  But  by then the damage will be done.

Already today near 3" near Wantage NJ...  who gets it tomorrow... please read on

 

Screen Shot 2021-07-16 at 5.55.25 PM.png

Screen Shot 2021-07-16 at 5.58.00 PM.png

  • Like 2
Link to comment
Share on other sites

Expect NOT widespread 4-5", instead widespread 0.2-1.2" with a band or two of 4-5" probably somewhere near the 90F heat which will be in NJ (Probably D4 modest heatwave in most of NJ except coastal waters).

This eve's 1-3" nw NJ in the digital storm total radar band previously shown. My  Wantage (this southern part) total 1.12.  

Will try and reevaluate potential early tomorrow morning. 12z/16 SPC HREF under played the max by about 1" ending 8PM this evening.  

SPC HREF seems to favor, imo, ne NJ received ing the most by daybreak Sunday, starting this evening.  As others have said,  we shall see.

 

Screen Shot 2021-07-16 at 8.40.04 PM.png

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

35 minutes ago, BombsAway1288 said:

Last time they hoisted FFW 24hrs in advance it failed miserably. They're the pro's so I guess time will tell.

What do you want them to do, issue a FFW for one or two counties? 

The ffw is warranted. Some places will miss and some places may flood. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...