Hoisting the Sultan Signal: Heavy Rain Event July 5-7

[WxWatcher007]

Big heat is gone for now and we quickly turn our attention to an unusual summer setup. Weak high to the north, a weak low to the south, and an all-important warm front which will wring out PWATs of 1.5-2.0" between late tonight and Tuesday. Flood watches are up for CT, which may be expanded depending on where the axis of heaviest rain sets up. 

Ensemble guidance has a heavy rain signal

 

 

Some high resolution guidance goes wild. 

 

The main takeaway is that while there may be a sizable area of meaningful rain (my forecast is 2-4 generally for CT) there is high end localized flash flooding potential where the warm front sets up. Most models have been fairly consistent in focusing the heaviest general and localized rain in SNE. 

For most, the mitigating factors here are 1) Outside of the axis of heaviest rain this is likely to be a spread out rainfall over many hours rather than short burst deluge and 2) antecedent conditions have been relatively dry, though many in CT have seen rain in recent days. 

Let's discuss. Let's flood.  

[OceanStWx]

I'm just over here saying that whenever you see most (all?) of guidance spitting out some big numbers, it usually happens somewhere in a roughly CWA-sized area. The difficult part here is that this could be anywhere in the BOX/ALY/OKX CWAs.

[OceanStWx]

I think a good example is to watch the convection in the BGM CWA. It's not moving much. That is what will drift east over the next couple of days.

[Sey-Mour Snow]

[WxWatcher007]

Yeah if I had to guess southern CT/Long Island is where the flooding happens. 

[dendrite]

Let’s get ISP another foot of rain in a few hours. 

[WxWatcher007]

20 minutes ago, dendrite said:

Let’s get ISP another foot of rain in a few hours. 

BDR to ISP flood while Kev and I get sprinkles? 

[ineedsnow]

[dendrite]

4 minutes ago, WxWatcher007 said:

BDR to ISP flood while Kev and I get sprinkles? 

Kev will get 4” and make some kind of “pleasantly surprised” post. Then the following week it’ll be another concern. 

[Damage In Tolland]

28 minutes ago, WxWatcher007 said:

Yeah if I had to guess southern CT/Long Island is where the flooding happens. 

I think that is possible as but more likely is Philly to NNJ /NYC corridor . N CT has been bone dry since June 1.. so even if a few inches managed to fall there shouldn’t be any issues . S CT has been much wetter so they could have a few issues if they ended up training 

[Damage In Tolland]

9 minutes ago, WxWatcher007 said:

BDR to ISP flood while Kev and I get sprinkles? 

I still think .50-.75 is the best forecast around here . An inch of things break right 

[kdxken]

6 minutes ago, ineedsnow said:

Don't like the trend of heavy rain in Massachusetts. Models initially contained it south of the pike. No longer. I'll be lucky if only an inch and a half.

 

[Damage In Tolland]

5 minutes ago, dendrite said:

Kev will get 4” and make some kind of “pleasantly surprised” post. Then the following week it’ll be another concern. 

I’ll make a deal. If your forecast ends up correct and I get 4” or more, I will not make one mention of Stein the rest of this summer 

[Damage In Tolland]

Just now, kdxken said:

Don't like the trend of heavy rain in Massachusetts. Models initially contained it south of the pike. No longer. I'll be lucky if only an inch and a half.

 

What models besides the NAM and HREF which is NAM based ?

[OceanStWx]

Just now, Damage In Tolland said:

What models besides the NAM and HREF which is NAM based ?

  It's 20% NAM. 

[CT Rain]

21 minutes ago, Damage In Tolland said:

I think that is possible as but more likely is Philly to NNJ /NYC corridor . N CT has been bone dry since June 1.. so even if a few inches managed to fall there shouldn’t be any issues . S CT has been much wetter so they could have a few issues if they ended up training 

I got like 1.25" yesterday. 

[Damage In Tolland]

1 minute ago, CT Rain said:

I got like 1.25" yesterday. 

Well aren’t you central CT? 

[Baroclinic Zone]

Hep us here.

need the rain.

[kdxken]

26 minutes ago, Damage In Tolland said:

What models besides the NAM and HREF which is NAM based ?

 

[Amped]

No model had the giant blob convective blob east of Pittsburgh. Thats where the heaviest rain is arm.

[Great Snow 1717]

1 hour ago, kdxken said:

Don't like the trend of heavy rain in Massachusetts. Models initially contained it south of the pike. No longer. I'll be lucky if only an inch and a half.

 

That map is a great "practice" map for the methuen area this winter...

 

[TauntonBlizzard2013]

1 hour ago, Baroclinic Zone said:

Hep us here.

need the rain.

Yup. Bone dry here 

[CT Valley Snowman]

1.66 since June 1 at a nearby PWS in Enfield.  Let's see how this works out.  

[WxWatcher007]

Oof

[kdxken]

7 minutes ago, WxWatcher007 said:

Oof

 

New one to me. 

 

[OceanStWx]

1 minute ago, kdxken said:

 

New one to me. 

It's a pretty cool visualization tool. More shading means that more ensemble members are showing something anomalous for the time of year. More black lines with higher numbers mean the most extreme ensemble members are quite extreme.

[BrianW]

Man look at those training cells out west over NY. Someone is going to get absolutely crushed. 

Wonder if we see a repeat of 08/17/2024.

 

 

 

[kdxken]

Pretty cool.

[WxWatcher007]

NAM still pretty aggressive across CT. Several flood reports in PA tonight. 

[powderfreak]

South coast smoked on NAM and HRRR.