2026 Mid-Atlantic Severe Storm General Discussion

[Kmlwx]

I'm doing it....the 2026 iteration starts today. With potential warm weather on the horizon, we will likely see the start of the pencil thing gusty shower line season. 

@yoda - I feel like you're usually on board with early tracking with me. 

Excited to get back to our smaller spring/summer crew...The winter weenies can take their bickering away soon enough. As much as I hate summer heat - I tolerate it for thunderstorms. 

And now....I will go back to watching CFS/weeklies/CSU-MLP/CIPS pages for signs of our first threats! 

[George BM]

2 hours ago, Kmlwx said:

I'm doing it....the 2026 iteration starts today. With potential warm weather on the horizon, we will likely see the start of the pencil thing gusty shower line season. 

@yoda - I feel like you're usually on board with early tracking with me. 

Excited to get back to our smaller spring/summer crew...The winter weenies can take their bickering away soon enough. As much as I hate summer heat - I tolerate it for thunderstorms. 

And now....I will go back to watching CFS/weeklies/CSU-MLP/CIPS pages for signs of our first threats! 

Remember... the new type of convective outlooks come out starting next week with the 1630z Day 1 March 3rd outlook.

https://www.spc.noaa.gov/exper/conditional-intensity-information/

 

 

 

 

[Kmlwx]

I wasn't aware of this! I've been not monitoring as closely due to work. Thank you!!! Imagine a 90% wind  

[Eskimo Joe]

I can't decipher these new outlooks. My astigmatism makes these hatched maps almost unreadable. 

[Kmlwx]

The 2nd half of the coming week has some minor potential. GFS has some modest supercell composite parameters - and even the Euro has some instability around. Interesting enough for early March, at least. Nothing substantial, of course. 

CSU-MLP has some minor probs painted over some of our area Friday. 

[Kmlwx]

19 hours ago, Eskimo Joe said:

I can't decipher these new outlooks. My astigmatism makes these hatched maps almost unreadable. 

It's definitely a little wacky looking - I'm not sure other than doing completely separate color-coded maps how they could have implemented this differently. I like the idea/principle, though! 

[Kmlwx]

The CFS monthlies seemingly have a potential NW flow H5 pattern (at least in general/smoothed terms) same with CanSIPS. For June. 

[high risk]

Nice to see the thread ready to go for the upcoming season!

[yoda]

Hmmm... sneaky severe this evening?

 

[Kmlwx]

I think there could be some non-zero chances into next week. CSU MLP page looks "decent enough for this time of year" for next Wednesday, for example. It's always going to be slim pickings in March (and even most of April) - but I'm intrigued that as soon as warmer temps rolled in some of the predictive tools ramped up just a touch. 

Give us some unseasonably warm/humid days in April into May and something will probably pop off with how dynamics systems can still be that time of year. 

[high risk]

2 hours ago, yoda said:

Hmmm... sneaky severe this evening?

         Way too stable for severe east of the mountains, but there will be some elevated instability, so I expect some thunder during the evening / overnight, especially for areas north of 66 (VA) and 50 (MD).

[Stormchaserchuck1]

Pretty nice cell in eastern West Virginia. maybe some small hail.

[WxUnit]

Pretty good cell going in West Virginia. Tagged for a possible tornado as well. 

[SnowenOutThere]

Had first thunder of the season!

[yoda]

Seems could be interesting out west tomorrow afternoon into night?  Afternoon discussion from LWX 

We`re expecting two rounds of storms tomorrow. The first round
is expected to form within a surface trough just to the east of
the Alleghenies during the mid-late afternoon hours. Model
soundings show a fair amount of dry air in place aloft, and
large scale forcing for ascent won`t be overly strong, so areal
coverage with this first round of storms is only expected to be
isolated to scattered in nature. If storms do become well
established, the background environment will have enough
instability (around 1000 J/kg of MLCAPE) and shear (around 40
knots in the 0-6 km layer) to promote updraft rotation.
Isolated instances of damaging winds or hail may be possible
with these storms as they move eastward from the Potomac
Highlands toward the I-81 corridor and then the Blue
Ridge/Catoctins during the mid-late afternoon hours. Conditions
will likely remain dry to the east of US-15 during the daylight
hours.

A second round of pre-existing storms will approach from the
Ohio Valley, reaching the Allegheny Front around sunset. This
round of storms could be well organized into a squall line, and
may potentially be quite intense. With the loss of daytime
heating, the trend will likely be downward with the strength of
this activity as it moves into our area, but damaging winds may
still be possible, especially along and west of the Allegheny
Front. Large scale forcing for ascent may enable these storms
to hold together in a weakened form as they move eastward across
the forecast area during the first half of the night.

As of now, SPC has Garrett County in Slight Risk for severe
thunderstorms, with locations further east to about US-15 in a
Marginal Risk.

[Jebman]

You guys are gonna get LOTS of interesting severe weather this season.

[Jebman]

You guys are gonna get LOTS of interesting severe weather this season.

[Kmlwx]

CSU MLP has increased our odds for Wednesday. 

[yoda]

LWX AFD from this afternoon on Wednesday into Thursday 

KEY MESSAGE 2.. A strong cold front brings gusty winds, colder
temperatures, and widespread shower/thunderstorm chances starting
Wednesday.

Not too much change in regards to timing or hazards for the midweek
period. Still monitoring the deep digging upper level trough
dropping down out the Great Lakes region as well as a piece of
southern stream energy ejecting out of the southern Plains region.
At the surface, will lay a strong cold frontal boundary which will
flip the script when it comes to late Winter and early Spring. 6/12z
guidance still has this front progged to move through the area some
time late Wednesday into Thursday. As for severe weather, it will be
highly dependent on timing with a focus remaining west of the Blue
Ridge. This is the area where better instability and shear may be
maximized given a lead shortwave that should touch off some
convection over the mountains Wednesday afternoon as the northern
stream trough tries to take a negative tilt. CSU learning machine
probabilities remain around 15 to 30 percent for all severe hazards
for the entirety of the area Wednesday afternoon into Thursday. NSSL
probabilities are quite similar with a focus more on areas west of
US-15 and out across the Allegheny Mountains.

Meanwhile, SPC continues to highlight a 15 percent probability
zone for portions of Garrett Co. MD during the Day 4 (Wednesday
into Thursday). Storms will have plenty of fuel to work with as
temperatures surge into the 70s and low 80s with dewpoint
factors getting into the upper 50s and low 60s. Shear is a bit
more uncertain with strong southwesterly flow at the surface
ahead of the front and gusty northwesterly flow likely behind
the front heading into the Thursday timeframe. Also, any early
convection over the mountains combined with a later timing of
the front (i.e Wednesday night into Thursday) could hamper
convective output. Wind and heavy rainfall would be the primary
threats for storms if they can develop Wednesday afternoon into
Wednesday night.

The bigger story with the front will be the notable drop in
temperatures heading into late week. Temperatures will take a 15 to
25 degree dive Thursday with highs ranging from the 30s over the
mountains to low 60s east of I-95 and across southern MD/central VA
Piedmont. Some anafrontal snow is even possible in the Alleghenies
as the front departs Thursday afternoon into Thursday evening.
Temperatures do level out Friday with highs in the upper 40s over
northeast MD/the Alleghenies and mid to upper 50s elsewhere across
the region. Similar values are expected this weekend despite another
front passing through the region.

 

[yoda]

12z NAM looked a lil intriguing with its soundings at hrs 78 to 84 across the region.  Granted it can change next run of course and its at range... but looks like our first real chance of severe 

[high risk]

6 hours ago, yoda said:

12z NAM looked a lil intriguing with its soundings at hrs 78 to 84 across the region.  Granted it can change next run of course and its at range... but looks like our first real chance of severe 

        Soundings for later Wednesday do look interesting, but what will trigger storms?   Maybe there is a subtle shortwave in the flow to do something, and the ECMWF admittedly does suggest a couple of open warm sector storms, but I'm skeptical.   It appears that the strong forcing won't arrive until early Thursday, the most unfavorable time of day possible for this setup.

[yoda]

SPC opens Day 3 severe bidding with SLGT risk i81 corridor west and MRGL for the rest of us

[Kmlwx]

Likely first MEH of the year for us. Woooooooo storms! 

[dailylurker]

14 minutes ago, Kmlwx said:

Likely first MEH of the year for us. Woooooooo storms! 

LNFG! 

[high risk]

4 hours ago, yoda said:

SPC opens Day 3 severe bidding with SLGT risk i81 corridor west and MRGL for the rest of us

           As I noted earlier, I was down on the chances, because I'm not sure what would trigger storms during peak heating.   The HiResW FV3, RRFS, and ECMWF do all suggest cells in our area, however, Wednesday afternoon in an overall somewhat favorable environment, so I can't ignore that.

[SnowenOutThere]

25 minutes ago, high risk said:

           As I noted earlier, I was down on the chances, because I'm not sure what would trigger storms during peak heating.   The HiResW FV3, RRFS, and ECMWF do all suggest cells in our area, however, Wednesday afternoon in an overall somewhat favorable environment, so I can't ignore that.

FV3 soundings seem legit as the squall line approaches. Steep (nearly unconditionally unstable lmao) low level lapse rates. Decent turning of wind with height and sheer increase. Just lacking in the cape department past the LCL. Would need just a bit of a trigger to get some storms I think considering the lower levels lapse rates. 

[yoda]

Good afternoon discussion from LWX 

KEY MESSAGE 2... Strong to severe thunderstorms are possible
west of I-95 Wednesday afternoon and evening as a strong cold
front pushes through. A significant drop in temperatures and
gusty winds will accompany the front Thursday.

Still monitoring the progression of a deep digging positively
northern stream trough out of the Great Lakes and it`s associated
strong cold front which looks to cross the area during the late
Wednesday into Thursday timeframe. Meanwhile, southern stream energy
will be lifting northward ahead of the boundary Wednesday afternoon
and evening.

SPC currently has a Slight Risk (Level 2 out 5) west of a line from
from Frederick/Hagerstown, MD southwest toward
Strasburg/Harrisonburg/Monterey, VA. There is a Marginal Risk (Level
1 out of 5) east of these areas (including both the DC/Baltimore
metros) with a focus mainly west of I-95. The primary threat with
storms would be wind and locally heavy rainfall. Secondary threats
would include an isolated tornado given the increased shear/helicity
and large hail with dry air aloft. CSU probabilities remain between
15 to 30 percent for all severe hazards areawide while NSSL/NCAR
probs generally focus on areas, mainly west of US-15 and in
particularly west of the Blue Ridge. CIPS probabilities remain less
than 10 percent for this event.

Plenty of uncertainty remain in regards to the severe weather threat
Wednesday into Thursday. Timing will be important along with cloud
cover. 6z/12z model soundings from KCHO, KIAD, and KHGR all have
hints of a capping inversion which could squander convective
development. The question is to if the cap breaks and to when it
happens with a focus west of Frederick, MD down toward the I-66/US-
50 corridor and points west per the latest CAM guidance. One or two
strong storms could fire within the warm sector Wednesday afternoon
along a lead shortwave trough out ahead of the cold frontal
boundary. Any of these storms could become severe (i.e either
multicellular clusters or supercells) given the added shear and
instability to work with. Confidence drops off with the severe
threat along the immediate cold front given the projected timing
late evening into the overnight period. Even with that said, a gusty
line of shower could exist Wednesday night into Thursday as the
front pushes through. The severe threat diminishes Thursday as the
front pushes through. Expect any residual moisture over the
mountains to change to snow with coating to 1" expected on
grassy/elevated surfaces.