2026 Mid-Atlantic Severe Storm General Discussion

[yoda]

DCA at 00z Tuesday 12z NAM 

 

[Kmlwx]

The CAMs (to varying degrees) all have decent amounts of storm coverage too - unlike some of the prior events recently. 

[vortex95]

16 hours ago, high risk said:

Monday has my attention.     The parameter space won't be high end, but we should have modest instability, deep layer shear, and dynamics.   Timing of day is good.     And there are even suggestions of some low-level shear, potentially eventually leading to 5% TOR outlook.

I've noticed that if a 5% tor risk is present, that almost always means a tor watch is issued.

[mappy]

Methinks we won’t be playing softball tomorrow night 

[Kmlwx]

I'm more "in" on this one than the prior events. It could still fizzle - and I certainly don't think it's going to be an "outbreak" - but storm coverage has higher confidence it seems - and the shear does raise some eyebrows!

Also I'll be in the office - which seems to guarantee good storms (my office is in the core of the building with no windows - so I essentially miss anything that happens during cool events). 

[vortex95]

1 hour ago, Kmlwx said:

The CAMs (to varying degrees) all have decent amounts of storm coverage too - unlike some of the prior events recently. 

HRRR and RRFS have meaty storms and in two distinct waves.  However, CAPE is rather low for this time of year for a svr event.  Hodographs look better on the NAM/HRRR but not so much on the RRFS.

0-3 km CAPE is lacking on the HRRR and RRFS, so I have to wonder about tor potential.

It is fairly strong s/w for June passing just to our N and overall wind fields are good, so perhaps the dynamical part will make up for the rather low CAPE and that's why the HRRR and RRFS show meaty storms.  PWATs ramp up nicely during the day.  K-indices fcst get to upper 30s so likely big rain producers.

[Kmlwx]

2 minutes ago, vortex95 said:

HRRR and RRFS have meaty storms and in two distinct waves.  However, CAPE is rather low for this time of year for a svr event.  Hodographs look better on the NAM/HRRR but no so much on the RRFS.

0-3 km CAPE is lacking on the HRRR and RRFS, so I have to wonder about tor potential.

It is fairly strong s/w for June passing just to our N and overall wind fields are good, so perhaps the dynamical part will make up for the rather low CAPE and that's why the HRRR and RRFS show meaty storms.  PWATs ramp up nicely during the day.  K-indices fcst get to upper 30s so likely big rain producers.

I've heard (usually from @high risk ) that the HRRR tends to overmix out low level moisture - could that be a factor here?

[Kmlwx]

FWIW - the 12z CSU MLP maps have reduced quite a bit. 

[batmanbrad]

not much change in the newest SPC day 2 outlook for our area, they held the TOR prob at 2% and mentioned too much uncertainty about degree of destabilization to warrant upgrading to 5%

[SnowenOutThere]

2 hours ago, vortex95 said:

HRRR and RRFS have meaty storms and in two distinct waves.  However, CAPE is rather low for this time of year for a svr event.  Hodographs look better on the NAM/HRRR but not so much on the RRFS.

0-3 km CAPE is lacking on the HRRR and RRFS, so I have to wonder about tor potential.

It is fairly strong s/w for June passing just to our N and overall wind fields are good, so perhaps the dynamical part will make up for the rather low CAPE and that's why the HRRR and RRFS show meaty storms.  PWATs ramp up nicely during the day.  K-indices fcst get to upper 30s so likely big rain producers.

Its the RRFS but man those are some nasty updraft helicity tracks. Most I've seen for this area on any model. 

[SnowenOutThere]

2 hours ago, Kmlwx said:

I've heard (usually from @high risk ) that the HRRR tends to overmix out low level moisture - could that be a factor here?

It mixes tomorrow into the upper 50s for dewpoints, NAM stays in the mid to upper 60s. 

[Ellinwood]

15/5/2 wind/hail/tor on the 06z Day 1... seems reasonable, but I could see a bump up to 30/5/5 this afternoon (no hatches) once we see how things are actually playing out coverage-wise. More confident with the wind coverage bump up than the tor. Shear's there, but the mid-to-high cloud cover loves messing up our setups.

[Kmlwx]

Good amount of sun on the way to work this morning. 

[batmanbrad]

does look clear esp. over MoCo as of now, though there are some clouds to the west so unless those dissipate as they move out of the mountains, we'll probably have intervals of both clear skies and some cloud cover:

 

[Kmlwx]

No changes really on the 13z SPC outlook. 

[Kmlwx]

The 12z CSU MLP update re-increased the 5% area for TOR and also inched the 30% wind closer to MBY. 

[JakkelWx]

the dew has fallen into the low 60s here, but its 92. doesnt exactly feel unstable out there. the extreme dryness plays a big part.

[yoda]

Watch coming by 3pm

 

[yoda]

Mesoscale Discussion 1253
   NWS Storm Prediction Center Norman OK
   1225 PM CDT Mon Jun 22 2026

   Areas affected...portions of the central Appalachians into the
   Mid-Atlantic

   Concerning...Severe potential...Watch likely 

   Valid 221725Z - 221930Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Thunderstorms will increase in coverage and intensity over
   the next couple of hours. Scattered damaging wind gusts, isolated
   hail and perhaps a tornado will be possible through evening. A
   severe thunderstorm watch will likely be needed by 19z.

   DISCUSSION...Thunderstorms over the higher terrain of WV and
   vicinity are gradually increasing in intensity this afternoon as
   gradual destabilization occurs. Downstream from higher terrain
   across portions of VA into MD/DE, southern NJ and southeast PA,
   stronger heating is occurring within areas of mostly clear skies.
   Higher quality moisture across eastern VA has been streaming
   northward toward southeast PA/southern NJ and ensuing stronger
   destabilization is noted. Enhanced westerly flow is apparent in
   early afternoon mesoanalysis and 12z regional RAOBs. This should
   allow for sufficient deep layer shear for storm organization.
   Thunderstorm clusters will pose mainly a risk of damaging wind gusts
   given steep (greater than 7.5 C/km) 0-3 km lapse rates and PW values
   around 1.75 inches. 

   Some forecast guidance suggests sufficient clustering/outflow
   consolidation may occur in the vicinity of northern VA/MD and a
   forward propagating cluster/bowing segment could develop and track
   northeast with time toward southeast PA/NJ. This corridor aligns
   with the corridor of stronger midlevel westerlies, and may pose a
   relative greater severe risk compared to points further south into
   southern VA and NC where flow is weaker. If this scenario unfolds,
   damaging wind potential will increase. Given modest 0-1 km SRH
   across the region, a tornado or two also could occur, though the
   damaging wind risk is expected to be the primary hazard into early
   evening.

   ..Leitman/Hart.. 06/22/2026

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...PHI...AKQ...CTP...LWX...RAH...RNK...PBZ...RLX...
   GSP...MRX...JKL...

   LAT...LON   40497808 40747686 40807597 40757507 40587476 40047426
               39677428 38847474 38197525 37847570 37297702 36447933
               36097997 35748149 35858253 36268338 36608350 36928354
               37748308 38378233 39148140 40177908 40497808 

   MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN

 

[Kmlwx]

Yeah CAMs have been *relatively* consistent with pushing some sort of loose cluster of storms through the DC area. 

[batmanbrad]

for those hoping for at least drought-denting rainfall, WPC shares some decent possibilities in their latest ERO/ERD:

...Central Appalachians to Northeast U.S...

Surface low currently analyzed over the western Ohio Valley will
gradually lift to the east-northeast with an expectation for the
low center to exit off the northern Mid Atlantic coast, dragging a
cold front through the Mid Atlantic and Ohio Valley and lifting a
warm front ahead of the disturbance. The current indications are
for convection to spawn over the eastern Ohio Valley by the early-
afternoon as mid-level ascent and increased surface forcing aided
by the cold front and area of low pressure will trigger convective
initiation just upstream of the terrain in WV and western PA. This
area of thunderstorms will migrate eastward, entering a favorable
environment within a modest warm sector as you move east of the
Appalachian front. Shear profiles across the Mid Atlantic are
anticipated to be greatest north of the Mason Dixon, however shear
magnitudes are still capable for enabling stronger mid-level
mesocyclones to materialize and hold as far south as I-66 leading
to prospects for heavier thunderstorms to hold across the urban
corridor extending from northern VA up through NYC and western LI.

HREF probs for >1" are pretty high for both the neighborhood and
EAS fields meaning there's a consensus for areas of heavy rainfall
to impact much of the Mid Atlantic with the most pronounced
signatures into the Central Appalachians and the urban centers,
both are which are susceptible to flash flood concerns. Antecedent
soil moisture is dry, so the initial burst of rainfall will be
beneficial to those areas not tied completely by urban
infrastructure, however, there's a sufficient signal in the QPF
means to maintain the previous SLGT risk inherited for the region
as 00z CAMs maintained their depictions on a multi-round cycle of
convection moving into the area with pockets of 2-3+" forecast
across portions of the aforementioned areas.
 

[SnowenOutThere]

I’m sorta feeling today. At the bare minimum we’re over 1000 SCAPE right now so I think we will at least get some storms this evening.  

[Kmlwx]

The watch has been issued. 

[Kmlwx]

The cell near Moorefield, WV intensified relatively quickly. We'll see how things trend the next 1-2 hours. 

[Kmlwx]

Warned storm approaching Luray looks semi-interesting on velocity. 

[SnowenOutThere]

7 minutes ago, Kmlwx said:

Warned storm approaching Luray looks semi-interesting on velocity. 

Debating if I want to drive out on a local chase. Would set up east of Culpepper. 

[Kmlwx]

It's overall a very messy looking radar so far. 

[SnowenOutThere]

Just now, Kmlwx said:

It's overall a very messy looking radar so far. 

Cell south of dc has a weak mesocyclone 

[SnowenOutThere]

1 minute ago, SnowenOutThere said:

Cell south of dc has a weak mesocyclone 

DCA radar shows it well

[batmanbrad]

WPC just issued an MPD for our area - warns of heavy rain leading to possible flash flooding:

https://www.wpc.ncep.noaa.gov/metwatch/metwatch_mpd_multi.php?md=0499&yr=2026