2026 Mid-Atlantic Severe Storm General Discussion

[high risk]

1 hour ago, Kmlwx said:

The CAMs are really all over the place (seems to be a common theme this year). I could technically see chunks of the area getting skunked through the whole week...The game of weather lottery! 

 Even this evening has a lot of questions.  While there is general agreement that a cluster of storms drops south through NJ/DE, some of the CAMs have storms building back to the west and catching much of central MD.

[yoda]

Severe Thunderstorm Watch up until midnight for NE MD and DE 

URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 638
   NWS Storm Prediction Center Norman OK
   435 PM EDT Tue Sep 1 2026

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     Delaware
     Northeast Maryland
     New Jersey
     Southern New York
     Central and Eastern Pennsylvania
     Coastal Waters

   * Effective this Tuesday afternoon from 435 PM until Midnight
     EDT.

   * Primary threats include...
     Scattered damaging wind gusts to 70 mph likely
     Scattered large hail events to 1.5 inches in diameter possible
     A tornado or two possible

   SUMMARY...Supercell thunderstorms should pose a threat for large
   hail this afternoon as they track east-southeastward across the
   northern Mid-Atlantic. The threat for scattered severe/damaging
   winds should increase this evening as one or more clusters develops.
   A tornado or two may also occur with any sustained supercell.

 

[yoda]

 

[The Dude]

19 minutes ago, high risk said:

 Even this evening has a lot of questions.  While there is general agreement that a cluster of storms drops south through NJ/DE, some of the CAMs have storms building back to the west and catching much of central MD.

Dumb question:  When folks are referencing the CAMs here, which models are you looking at.  I assume the HRRR, NAM Nest, RRFS.  Any others?  FV3, WRF-ARW? 

[high risk]

1 hour ago, The Dude said:

Dumb question:  When folks are referencing the CAMs here, which models are you looking at.  I assume the HRRR, NAM Nest, RRFS.  Any others?  FV3, WRF-ARW? 

 

        Correct.   HRRR, NAM Nest, RRFS, and the three Hires Windows (FV3, ARW, ARW2).

 

[yoda]

12 minutes ago, high risk said:

 

        Correct.   HRRR, NAM Nest, RRFS, and the three Hires Windows (FV3, ARW, ARW2).

 

What about the MPAS?

[high risk]

24 minutes ago, yoda said:

What about the MPAS?

      I personally don't look at it very often, as it's still being tweaked.   That said, it's the future, so as it matures, I'll definitely be looking more often.   

[vortex95]

Around 8pm this evening looking N from the N side of the Beltway, I could see robust ACCAS, almost MDT CU.  So there is your elevated instability in place.  RRFS MPAS suggest a few cells may form in the DC area the next few hrs (DCA already reporting LTGIC NE), and we have those storms in the far nrn Delmarva w/ a distinct OFB.

The EIR sat loop is impressive.  Look at the backbuilding and sharp cloud temp gradient in far NE MD.  NW flow is neat!

Got this loop from here.  Nice sector for the region!
https://whirlwind.aos.wisc.edu/~wxp/goes16/ircm/goes16_ne_3h.html

[dailylurker]

I see our storms for later on over Lake Erie this morning. Lake Ontario also has a nice batch.

[WxUSAF]

1 hour ago, dailylurker said:

I see our storms for later on over Lake Erie this morning. Lake Ontario also has a nice batch.

10z hrrr made a big flip to carrying that Erie (I call it Lake Freedom now) cluster into central MD

[TSSN+]

5 minutes ago, WxUSAF said:

10z hrrr made a big flip to carrying that Erie (I call it Lake Freedom now) cluster into central MD

The models haven’t done well showing the storms. Yesterday those storms that ripped ne and eastern Pa weren’t super well shown either. If that area holds together as the atmosphere gets unstable it could be an interesting afternoon. 

[dailylurker]

5 minutes ago, WxUSAF said:

10z hrrr made a big flip to carrying that Erie (I call it Lake Freedom now) cluster into central MD

This post caused an eagle to gain it's wings.

It should be a fin day of radar watching. I could really go for some severe. I might cut out of work around 2 and do a lightning chase this afternoon. 

[batmanbrad]

the 2AM SPC outlook pulled the 2% TOR risk down into much of our area, and the 30% wind prob into much of the northern parts of our area.  CSU-MLP charts keep most of the TOR north of us but does agree with the 30+% wind area in our northern areas for today and keeps that going with even more of our area covered into tomorrow.  Let's see if this holds when the 9AM SPC outlook for today comes out.  Still many variables to sort out but should be an interesting next 36 hours or so to track!

[SolidIcewx]

Optimally, id like to see it develop more west as the morning goes on. That way it increases the chances of a wider hit for us all this evening.

[TSSN+]

Got multiple tornado warnings and severe warnings but no watch up there.