2026 Mid-Atlantic Severe Storm General Discussion

[vortex95]

Four days in a row svr risk in this area, esp. this time of year?  Sure ,lots of days get upgraded to slight risk the day of and we get 4 days in a row of svr risk, but to have days 3, 4, and 5 outlooked means synoptically it is defined and impressive, which means higher-end svr wx possible.

Usually in this part of the country, you don't get multiple days in a row w/ svr wx from NW or WNW flow b/c one wave of convection and it s/w trof clears things for moisture, and it takes a bit of time to recover.  Or the front/boundary gets pushed farther and farther S w/ each wave of convection.  But the way the mid and upper level ridge is during this period looks like it may force things to be in the same general area repeatedly.  Why not?  Every so often things do work out for relentless stormy wx in a region!

One might say, "4 days in a row, *everyone* should cash in and get crushed at least once during the period!"  I hope so.  W/ an EML present, you can do some nice things during the overnight hours, esp. with crazy LTG.
 

[vortex95]

On 8/30/2026 at 8:55 AM, stormy said:

Would this EML encouragement of strong storms be more likely for the western ridges or eastern lower elevations ?

I don't know,  Many times in WNW or NW flow, mountains to the W do well, then is often a gap due to downslope flow between IAD and DCA, and then it picks up again due to the bay breeze and higher dew points E of I95,

But its not easy tell on any given days the "DC split" occurs, and w/ an EML present, that makes it more complex b/c nighttime convection is more common and often not surface-based, so downslope flow is not as much of a factor.
 

[stormy]

1 hour ago, vortex95 said:

I don't know,  Many times in WNW or NW flow, mountains to the W do well, then is often a gap due to downslope flow between IAD and DCA, and then it picks up again due to the bay breeze and higher dew points E of I95,

But its not easy tell on any given days the "DC split" occurs, and w/ an EML present, that makes it more complex b/c nighttime convection is more common and often surface-bases, so downslope flow is not as much of a factor.
 

Yesterday evening, this northwest perimeter flow developed a strong storm in southwest Augusta.

A couple locations received close to 2 inches of rain while a few miles away, little more than sprinkles.

[Kmlwx]

I'm encouraged given the favorable things in place. Then again - we have been burned many times by so many different failure methods. Will be curious to see what guidance looks like as we go forward in time and how the AI/ML guidance trends. 

[SnowenOutThere]

2 hours ago, vortex95 said:

Four days in a row svr risk in this area, esp. this time of year?  Sure ,lots of days get upgraded to slight risk the day of and we get 4 days in a row of svr risk, but to have days 3, 4, and 5 outlooked means synoptically it is defined and impressive, which means higher-end svr wx possible.

Usually in this part of the country, you don't get multiple days in a row w/ svr wx from NW or WNW flow b/c one wave of convection and it s/w trof clears things for moisture, and it takes a bit of time to recover.  Or the front/boundary gets pushed farther and farther S w/ each wave of convection.  But the way the mid and upper level ridge is during this period looks like it may force things to be in the same general area repeatedly.  Why not?  Every so often things do work out for relentless stormy wx in a region!

One might say, "4 days in a row, *everyone* should cash in and get crushed at least once during the period!"  I hope so.  W/ an EML present, you can do some nice things during the overnight hours, esp. with crazy LTG.
 

Hoping Cvill can get in on the action once the ridge starts to break down towards the weekend. 

[Kmlwx]

1 hour ago, Kmlwx said:

I'm encouraged given the favorable things in place. Then again - we have been burned many times by so many different failure methods. Will be curious to see what guidance looks like as we go forward in time and how the AI/ML guidance trends. 

Quoting myself but now settled in at the office...

My hunch is that ONE of the day performs for many of us - whether it's divided up into 2 days remains to be seen. But even with what @vortex95 said - I think most of us would be skeptical of seeing consecutive days impact the exact same areas. 

Perhaps the first day hits the M/D line counties more and skunks the rest of us, then perhaps the next day is more of the metro area(s), then a bit too far south for the bulk of the subforum the following day.

[yoda]

12z NAM soundings seem to like Wednesday evening into Thursday morning (21z to 06z).  What i mean is they suggest some significant severe if everything came together

[Kmlwx]

That NAM run also suggests the EML plume (at least somewhat) will be in play. 

[Kmlwx]

Though I will also say both the NAM and the GFS keep favoring areas to our north and east...hopefully it can bleed south. 

[yoda]

Just now, Kmlwx said:

Though I will also say both the NAM and the GFS keep favoring areas to our north and east...hopefully it can bleed south. 

Well the NAM only goes out to 84... and IIRC, SPC didnt really focus on our region severe-wise until Thursday and Friday - which is near the end of its run and after.  

[Eskimo Joe]

3 hours ago, Kmlwx said:

That NAM run also suggests the EML plume (at least somewhat) will be in play. 

Never underestimate an EML in NW flow events.

Source: https://journals.ametsoc.org/view/journals/wefo/25/4/2010waf2222363_1.xml

[high risk]

Not much to add to the ongoing discussion:  trying to place and time particular events between now and the end of the week (best chances between Wednesday morning and Friday midday?) is likely to be futile, but higher end events in the Mid-Atlantic are certainly on the table.   A taste of the potential.....

 

[vortex95]

14 hours ago, stormy said:

Yesterday evening, this northwest perimeter flow developed a strong storm in southwest Augusta.

A couple locations received close to 2 inches of rain while a few miles away, little more than sprinkles.

I have only lived in the DC area for 8 years, and I am still trying to get an overall feel for local nuances when it comes to tstms, esp. when the "DC split" occurs.  That seems more than just a random coincidence.  And it is apparent the corridor from about 30 mi W of BWI to the city is a favorable area, so is just E of I95 to the Delmarva, and it seems really apparent CHO-RIC-ORF area in terms of a "hot spot!"  Also, w-cntrl and swrn VA get some really nicely-structured supercells at times!

[vortex95]

10 hours ago, Eskimo Joe said:

Never underestimate an EML in NW flow events.

Source: https://journals.ametsoc.org/view/journals/wefo/25/4/2010waf2222363_1.xml

Yes, NW flow events are *notorious* in New England for its biggest tor events and outbreaks.  Historically, it is a little less defined in the Mid-Atlantic b/c it does well in SW flow (College Park, Sep 2001) and TC events (remains of Ivan in Sep 2004), but you have June 23, 1944 (WV hit hard) and June 2, 1998 (Frostburg MD F4).
https://www.weather.gov/lwx/events_19980602
https://www.tornadotalk.com/june-2-1998-tornado-outbreak/

And, of course, the derecho on June 29, 2012.  I think an EML present is important for high-end derechos.
 

[high risk]

39 minutes ago, vortex95 said:

And, of course, the derecho on June 29, 2012.  I think an EML present is important for high-end derechos.
 

 

         I'd say that there isn't much doubt about it, especially in the East.    We've had several derechos over the year die an ugly death over the mountains to our west when no EML was in place downstream.   One event in 2000 led SPC to issue a rare PDS severe thunderstorm watch here due to an intense bow echo over southeast Ohio blasting east.    Our environment did not have an EML, and the Appalachians shredded the system - we ended up with line of showers featuring gusts to 30 kt.

 

[vortex95]

It appears today will remain capped.  HRRR and RRFS have next to nothing.  700 temps warm from around 8C at 06z to 11 C by 00z and 1000-500 thk gets to 580, so that should cap things off.

However, some nocturnal action appears possible as the BDF approaches from the NE.  The RRFS MPAS looks impressive at 03z.  It is on its own, but look at the MUCAPE axis on the HRRR at 07z Wed.

And Wed aftn looks good w/ the front NNW to SSE across the areas.  Surprised SPC does not have at least 2% tor risk in the area.
 

 

[Kmlwx]

SPC discusses potential/conditional need for CIG1 and higher probabilities for D2 depending on timing and such. 

[Eskimo Joe]

1 hour ago, Kmlwx said:

SPC discusses potential/conditional need for CIG1 and higher probabilities for D2 depending on timing and such. 

Wednesday and Thursday could be legit ENH or MOD for someone in the Northeast or Mid Atlantic.

[Kmlwx]

Also related but only partially - and apologies if already posted. Saint Louis University is sunsetting their meteorology program and discontinuing CIPS on their site. But Mizzou has agreed to start hosting it - the new link to CIPS is here --> https://analog.missouri.edu/

[Eskimo Joe]

33 minutes ago, Kmlwx said:

Also related but only partially - and apologies if already posted. Saint Louis University is sunsetting their meteorology program and discontinuing CIPS on their site. But Mizzou has agreed to start hosting it - the new link to CIPS is here --> https://analog.missouri.edu/

That's terrible news. St. Louis University has turned out some incredible meteorologists and climatologists.

[stormy]

I live about 27 miles northwest of Charlottesville as the crow flies. Therefore, I am conscious of weather occurrences in Charlottesville more than D.C..

Charlottesville has been blasted with a highly unusual repetition of strong to severe storms during the past 60 days. This is within a rectangular area that encompasses much of Nelson and Albemarle counties that has repeatedly been hammered with hail, high winds and heavy rain..

The Charlottesville-Albemarle airport about 9 miles north of town has had the wettest August of the past 65 years with 10.13" of rain.  This compares to a normal 3.73" for August.

This began during July when 5.99" fell at the airport. 

During August, west of the Blue Ridge has been dry with serious drought.   I would enjoy sharing the rain but am very happy to escape the severe storms!!  

[Kmlwx]

2 minutes ago, Eskimo Joe said:

That's terrible news. St. Louis University has turned out some incredible meteorologists and climatologists.

It sounds like it will be a process - but lack of budget/funding and retiring faculty. It's very unfortunate!

[midatlanticweather]

2 hours ago, Eskimo Joe said:

That's terrible news. St. Louis University has turned out some incredible meteorologists and climatologists.

It is OK - Weather Weenies have us covered! (OF COURSE tons of sarcasm)
 

It is bad news 

 

[MN Transplant]

2 hours ago, Eskimo Joe said:

That's terrible news. St. Louis University has turned out some incredible meteorologists and climatologists.

This is on the heels of Nebraska-Lincoln losing their department too.  There are new ones to balance out, but it is always sad to see departments close.

[yoda]

New Day 2 mentions higher chance for large hail and tornadoes

SLGT risk moved further south towards RIC 

[yoda]

Granted higher chance for this (bolded mine) is to our north

Day 2 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   1230 PM CDT Tue Sep 01 2026

   Valid 021200Z - 031200Z

   ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE EASTERN
   GREAT LAKES INTO MID-ATLANTIC AND OVER THE NORTHERN ROCKIES...

   ...SUMMARY...
   Severe thunderstorms are possible across portions of the eastern
   Great Lakes to the Mid-Atlantic Wednesday into Wednesday night.
   Damaging wind gusts are the main threat, though some large hail and
   a few tornadoes may also occur. Widely scattered severe gusts and
   more sporadic occurrences of large hail appear possible from the
   northern Rockies into northern High Plains Wednesday afternoon into
   night.

   ...Synopsis...

   A belt of 40-50+ kt mid-level winds will spread from the Great Lakes
   into the Northeast in tandem with a series of low-amplitude
   disturbances. Elsewhere, a negatively tilted shortwave trough and
   attending mid-level jet streak will progress through the northern
   Rockies Wednesday afternoon and evening. At the surface, the primary
   baroclinic zone is expected to extend from low pressure over James
   Bay through the Great Lakes and mid MO Valley into the northern High
   Plains. A backdoor front/quasi-stationary boundary will reside over
   the Mid-Atlantic, the specific location of which will be dictated by
   the extent of outflow associated with early-day storms and the
   strength of low-level ridging stretching from the Gulf of St.
   Lawrence through the Northeast.  


   ...Great Lakes into the Mid-Atlantic...

   As alluded to in the synopsis, thunderstorms may be ongoing at 12Z
   Wednesday from portions of WI and MI into NY and PA within a zone of
   forcing for ascent associated with a lead short-wave trough. The
   strongest storms will be capable of isolated occurrences of large
   hail and/or damaging winds as they spread east-southeast through the
   lower Great Lakes and Mid-Atlantic Wednesday morning. In the wake of
   the early-day convection, prevailing west-northwest mid-level flow
   will maintain a plume of relatively steep mid-level lapse rates
   (e.g., 7 C/km) atop boundary layer dewpoints in the upper 60s to low
   70s, yielding MLCAPE upwards of 2000-3000+ J/kg by afternoon from
   lower MI into western parts of NY and PA.

   Additional thunderstorms are expected during the afternoon from
   lower MI through the lower Great Lakes, aided by weak disturbances
   aloft and the moderate to strong instability forecast across the
   warm sector. The presence of 35-45 kt of effective bulk shear will
   support organized storm modes including supercells and bowing
   structures capable of large hail potentially approaching two inches
   and damaging wind gusts into Wednesday night. Tornado potential will
   be conditional on storm mode; however, the models do indicate
   stronger low-level winds and resultant larger SRH developing from
   southwest ON into NY and PA Wednesday afternoon into evening, where
   the greatest potential for a few tornadoes will exist.