2026 Mid-Atlantic Severe Storm General Discussion

[vortex95]

11 hours ago, JakkelWx said:

it happened again the same evening. woo storms!

I *never* get sick of +CGs, even when they do not strike close.  One time, I had one strike about 6 mi from me about 1 hr before sunset, and even though I did not see the bolt, the flash was unusually bright and "encompassing" (meaning it was bright all around me, not a flash in the distance) for the daylight hours, and I go, "ooo, there is going to be big thunder."  And I counted, 30 sec later, a really deep THUD!  The acoustics can be really bizarre!

[Eskimo Joe]

9 minutes ago, vortex95 said:

Or the Ivan tor day in Sep 2004?  What, like 40 tors in VA alone, and many clustered right up to the MD/VA border just W of DC!  I think that day is the only SPC MDT ever issued for a TC tor event.

There were so many tors in VA that day, that if you look at a map for the CONUS showing which month tors are most common for each state, VA says "September" -- all b/c of that Ivan tor day!  It shows how a single outlier event can skew climo big time.

Biggest tornado outbreak in this region. 

[Hank Scorpio]

52 minutes ago, Eskimo Joe said:

Biggest tornado outbreak in this region. 

That outbreak produced the one and only tornado I've ever seen. I was working at Dulles that day and very wisely ignored the "take shelter" commands issued via loud speaker. Instead I ran up onto the enclosed pedestrian bridge between terminal A and B just in time to watch the tornado drop near the main terminal.

[high risk]

Sign me up for the 00Z HRRR.

[high risk]

1 hour ago, vortex95 said:

Or the Ivan tor day in Sep 2004?  What, like 40 tors in VA alone, and many clustered right up to the MD/VA border just W of DC!  I think that day is the only SPC MDT ever issued for a TC tor event.

There were so many tors in VA that day, that if you look at a map for the CONUS showing which month tors are most common for each state, VA says "September" -- all b/c of that Ivan tor day!  It shows how a single outlier event can skew climo big time.

       

      SPC issued MDTs on back to back days with Ivan.   The first day over the southeast somewhat busted, as too much cloud cover limited instability.   On the second day, we did eventually get a MDT into parts of northern VA, but the threat was not obvious until it evolved in real time.    This was the initial outlook of the day.  The area with a 5% got a SLGT.    (The probabilities ramped up starting with the 1630Z outlook.)

       

[vortex95]

3 hours ago, high risk said:

Sign me up for the 00Z HRRR.

Wow.  You get the classic "discrete cells ahead of line" which you always have to watch closely for tor potential, then big clusters w/  training psbl and FF threat.

And now much of the DMV could do well on Wed as the front gets hung up w/ more training and FF threat.

The 00z HRRR is really big for QPF. 48 hr totals 5" max just NW of DC and a whopping nearly 12" max near WAL!  Well, we do need the rain.

00z RRFS is very similar to the HRRR for big QPF w/ the 5" max just S of DC and an 11" max near WAL.

Winds aloft look better than the last event for svr wx.  I esp. like the 250 mb speed max approaching late in the afternoon, so discrete supercells should sustain better.  Tor threat is there but not high-end.
 

[dailylurker]

Congrats fokes south and east today. Looks like 2-3" of rain and lots of storms. Models looks pretty unenthusiastic for central Maryland. Probably just the normal spots like Fredrick and Glen Burnie see action lol.  Crickets in here for a severe day.

[yoda]

Morning discussion from LWX on the threat today 

DISCUSSION...
KEY MESSAGE 1...Strong to severe thunderstorms are likely today,
with some thunderstorm risk lingering into Wednesday.

Higher dew points have been advecting into the area with
moisture and instability increasing in S/SW flow. So far shower
activity has been isolated and short lived. However, a subtle
shortwave is approaching, and some of the convection currently
across WV and SW VA could persist or redevelop across the area
through the early morning hours. Areas of stratus are also
forming. Both of these features could inhibit surface heating
this morning, although it does appear we should have some
partial sun by midday as the warm front continues to lift to the
north. This should be enough to allow temperatures to rise into
the mid 80s to lower 90s. Combined with dew points in the 70s,
at least moderate surface based instability should develop,
highest east of the Blue Ridge Mountains.

A seasonably strong trough will be approaching from the west,
providing forcing and anywhere between 30 and 50 kt of flow in
the cloud bearing layer. This will provide a favorable
environment for severe thunderstorms, with supercells and
clusters both possible. One initiation region will likely be
along the prefrontal/lee trough near or just east of the Blue
Ridge. These storms will likely affect the I-95 corridor between
mid afternoon and early evening. While these storms will
certainly carry severe potential, it is interesting to note on
average the 850-700 mb wind fields will be greater to our south
and west until late afternoon or early evening. Other details
remain unresolved, especially the effects of upstream convection
that moved through the upper Great Lakes and mid Mississippi
Valley. This could have some impact on how thunderstorms develop
across the Ohio Valley this afternoon and what subsequently
moves into western areas. If stronger/more widespread
convection does not move in from the Ohio Valley, there is some
potential there is a relative minimum in coverage between the
Blue Ridge and Alleghenies.

The coverage of afternoon storms and upstream effects will
determine what happens this evening as the strongest forcing
overspread the area along with increasing low level wind fields.
A second round of showers and thunderstorms will be possible for
some areas, though increasing low level stability may limit the
severe weather threat. It appears the evening/overnight coverage
could gradually shift to southern parts of the forecast area, or
even mostly to our south, potentially focusing on outflow from
earlier activity.

Damaging winds will be the primary severe hazard, although
large hail and a tornado or two are possible if supercells
develop. Some localized swaths of more considerable wind damage
are possible. Relatively speaking, the tornado threat is higher
to the north (and north of the CWA) closer to the warm front
and possibly closer to the Chesapeake Bay where low level winds
could be backed. With that said, forecast hodographs vary quite
a bit between models and also throughout time, so any relatively
higher threat will depend on the mesoscale details.

With precipitable water values increasing (over 2 inches east of
the Blue Ridge), any storm mergers and training along mesoscale
boundaries could result in localized flash flooding. Overall
storm motions will be progressive though, so this threat
appears too localized for a Flood Watch at the moment and will
continue to be evaluated. Additional areas to monitor will be
the Ohio Valley low level jet potentially leading to training
(looks to be mostly west of the area), and the evening low level
jet leading to backbuilding along any residual
outflow/convergence feature (best QPF signal is currently mostly
south of the forecast area).

[Kmlwx]

46 minutes ago, dailylurker said:

Congrats fokes south and east today. Looks like 2-3" of rain and lots of storms. Models looks pretty unenthusiastic for central Maryland. Probably just the normal spots like Fredrick and Glen Burnie see action lol.  Crickets in here for a severe day.

Our severe crew isn't always up super early (except @yoda who seems to never sleep lol). We don't do the wall-to-wall posting as well as the larger winter crowd. I'd expect by 9-10am you'll get some more of the folks posting in here. 

Pretty cloud in Colesville, MD right now. Haven't looked at visible sat yet though 

[aldie 22]

Light drizzle north of Winchester