Potential POCKETS 5+, at most MAX 12" rain by 18z Sunday. Suggest OBS Tue-Sunday only when exceeding 5". Already at 12z/Wed "tiny" pockets 5-7" I195 NNJ/NYC area

[wdrag]

Monitor NWS products including NHC and local offices from OKX and PHI. 

This Topic doesn't guarantee anything but serves as a platform for comment.  Suggest starting with actual 5+" rainfalls, or unusual flooding.  Note: WPC is already bullish on Tuesday's rainfall.

Tropical Debby remnants-east coast trough-RRQ upper level jet related pattern this week had WPC intermittently forecasting 7+" of rain in NJ and possibly coastal CT/LI.  PA and se NYS may also be involved in big rain.  PRE conditions may??? exist late this week (Fri-Sat?) but uncertain in our NYC subforum.   Added a few graphics.  

WPC overall has been advertising 5+ in its graphics for our area since 06z/4. 

Below is the WPC 7 day rainfall forecast based on ensembles etc. Sampler past 3 days rainfall via CoCoRaHs. Machine ECMWF EFI, Machine GEFS ARI and UFHS, WPC D2 excessive and their D5.  You'll note the GEFS machine tools extend beyond D5.   

This weeklong accumulative event may be over by Sunday the 11th. 

FFG is very dry south of I80, so far.  This could. change radically by Friday night. Ensemble river stage products right now are conservative but highlight I95 corridor in our area.  FFG for now is most vulnerable I80 northward in NJ. 

What to do?  Just think of what you may??? need to alter in your plans due to flooded roads/streams, cellars.  Potential doesn't mean it occurs. 727A/5

 

Initial title 

 Potential POCKETS 5-12" of rain by 18z Sunday. Suggest OBS Tue-Sunday only when exceeding 5".123411 

[Rtd208]

00z GEFS/CMCE/EPS

[Rtd208]

06z GEFS

[MJO812]

[jm1220]

Looking like the buried in the South outcome won’t happen so we have to see where it starts to get booted NE and if this hook back into the Carolinas really happens. Complex interactions-and way too early to determine what our outcome is. We can definitely get drenched and seems like this PRE type event tomorrow will really happen regardless 

[MJO812]

12z

[jm1220]

1 minute ago, MJO812 said:

12z

A lot depends on the strength of the Bermuda High which as we’ve seen is undermodeled much of the time. If it’s stronger it’ll track further west and we already see it strengthening because of the sharp turn back N to landfall in the Carolina’s. The heaviest rain with any Debby remnants will be west of the track. 

[Brian5671]

3 minutes ago, MJO812 said:

12z

definitely a west trend once 2nd LF takes place.   Not much time over water to re-strengthen verbatim

[MJO812]

1 minute ago, jm1220 said:

A lot depends on the strength of the Bermuda High which as we’ve seen is undermodeled much of the time. If it’s stronger it’ll track further west and we already see it strengthening because of the sharp turn back N to landfall in the Carolina’s. The heaviest rain with any Debby remnants will be west of the track. 

This is the closest the models have been to our area. 

Usually the heaviest rains always end up north and west of the area. 

[MJO812]

Just now, MJO812 said:

This is the closest the models have been to our area. 

Usually the heaviest rains always end up north and west of the area. 

Gfs finally caved

My vacation week and it rains lol

[Brian5671]

1 minute ago, MJO812 said:

Gfs finally caved

My vacation week and it rains lol

I doubt it rains for 5 straight days...

[psv88]

34 minutes ago, MJO812 said:

Gfs finally caved

My vacation week and it rains lol

Good, I’m happy for you. I hope it rains everyday for you on your break, just like you like it. 

[SACRUS]

Irene like totals being forecasted in the Northeast

 

2011 wettest Aug overall 

 

MAP is OF IRENE not Debby for reference

 

[uofmiami]

44 minutes ago, jm1220 said:

A lot depends on the strength of the Bermuda High which as we’ve seen is undermodeled much of the time. If it’s stronger it’ll track further west and we already see it strengthening because of the sharp turn back N to landfall in the Carolina’s. The heaviest rain with any Debby remnants will be west of the track. 

Watch where the front that comes through Tuesday night sets up.  Just S of us or over us & does it move back N with remnants of Debby heading our way Thursday into Friday.  Hopefully models resolve things better today into tonight on all these details.

[Stormlover74]

Nam thru Thursday evening. Most falls Thursday though not Tuesday/Wednesday 

[MANDA]

Posted yesterday in August thread.  Worst case is a PRE followed by Debby passing near or just to the east.  Moist tropical air would get lifted over frontal boundary into "cooler drier" air mass.

Will be interesting to see how remnants interact with upper trof and frontal boundary that will be floundering arcoss our area.  My opinion,  spatial area of excessive rainfall to be determined but confidence increasing locations in this forum see 5-7"+ totals.  Hopefully broken up over several days.  Just for reference Ida rains came in a 3-5 hour period.  Short term intense rainfall is by far worse than something spread out over a few days. Regardless, that does little to help river flooding but it does lessen the intense flash flooding that was associated with Ida.  Not suggesting this is Ida type event.   We'll see how this plays out.

[winterwarlock]

well no one expected Ida to cause those issues so definitely people should be aware of that for Tuesday night and looks like Thursday night

[Stormlover74]

9 minutes ago, MANDA said:

Posted yesterday in August thread.  Worst case is a PRE followed by Debby passing near or just to the east.  Moist tropical air would get lifted over frontal boundary into "cooler drier" air mass.

Will be interesting to see how remnants interact with upper trof and frontal boundary that will be floundering arcoss our area.  My opinion,  spatial area of excessive rainfall to be determined but confidence increasing locations in this forum see 5-7"+ totals.  Hopefully broken up over several days.  Just for reference Ida rains came in a 3-5 hour period.  Sort term intense rainfall is by far worse than something spread out over a few days. Regardless, that does little to help river flooding but it does lessen the intense flash flooding that was associated with Ida.  Not suggesting this is Ida type event.   We'll see how this plays out.

Yes thankfully this would be spread out over a few days. Ida was insane and something I never want to experience again

[Allsnow]

Icon has 2-4 inches of rain tomorrow 

[Allsnow]

1 minute ago, Allsnow said:

Icon has 2-4 inches of rain tomorrow 

Rgem as well 

[MANDA]

24 minutes ago, winterwarlock said:

well no one expected Ida to cause those issues so definitely people should be aware of that for Tuesday night and looks like Thursday night

Ida rains well well advertised at least 48 hours in advance.  Most guidance was printing out intense and excessive totals over a short time.  Maybe not the precise location but the threat was very real.

As to the actual effects from the intense short term rainfall I don't think anyone could grasp in advance how bad it was going to be.  I believe it was labeled a 1 in 1000 year event but don't quote me on that.  At least a 500 year event.  The death toll in NJ alone was beyond belief.

[Brian5671]

35 minutes ago, Allsnow said:

Icon has 2-4 inches of rain tomorrow 

looks like Tue night Wed?

[Stormlover74]

9 minutes ago, Brian5671 said:

looks like Tue night Wed?

Gfs has 2 to 4 but that's the total for the week

[Brian5671]

CMC moving west last 3 runs with the highest rain totals-maybe seeing a further west track of the low (best rains usually west of track)

[jm1220]

3 minutes ago, Brian5671 said:

CMC moving west last 3 runs with the highest rain totals-maybe seeing a further west track of the low (best rains usually west of track)

Yep, there’s always a front that sets up west of the track in these that dumps out all the tropical moisture and usually zilch other than a band or two east. Historically this happens in NJ/Hudson Valley but we’re still at the anything can happen range. This PRE for mid week looks more definite and that can cause flooding by itself. 

[Stormlover74]

1 minute ago, jm1220 said:

Yep, there’s always a front that sets up west of the track in these that dumps out all the tropical moisture and usually zilch other than a band or two east. Historically this happens in NJ/Hudson Valley but we’re still at the anything can happen range. This PRE for mid week looks more definite and that can cause flooding by itself. 

Yeah and you can see there's going to be an area in between that sees very little. Probably delmarva tidewater area

But yeah too early to speak definitively 

[Allsnow]

18 minutes ago, jm1220 said:

Yep, there’s always a front that sets up west of the track in these that dumps out all the tropical moisture and usually zilch other than a band or two east. Historically this happens in NJ/Hudson Valley but we’re still at the anything can happen range. This PRE for mid week looks more definite and that can cause flooding by itself. 

 

[Allsnow]

 

[Stormlover74]

Ukie 6-10" for all

[Rtd208]