2025 Severe Weather General Discussion

[Kmlwx]

9 minutes ago, high risk said:

Hard to ignore that signal, but the accompanying forecast sounding suggests that it would be elevated.  So it might be rotating, but the biggest threat from elevated supercells is hail, and the overall moist profile and weak lapse rates don’t really support decent hail.

At this point I just want some loud thunder to wake me up from my sleep underneath the WxWatcher blanket. 

[high risk]

1 hour ago, Kmlwx said:

At this point I just want some loud thunder to wake me up from my sleep underneath the WxWatcher blanket. 

          Based on the 00Z suite,  late night convection is pretty certain for areas along and north of I-70.   Whether any of it makes it south towards the lower parts of Howard and Montgomery is less clear.

[yoda]

Ok then - https://www.spc.noaa.gov/products/md/md0390.html

 

 

   Mesoscale Discussion 0390
   NWS Storm Prediction Center Norman OK
   0252 AM CDT Fri Apr 04 2025

   Areas affected...ern WV Pnhdl...nrn VA...MD...DC...srn PA...DE...srn
   NJ

   Concerning...Severe potential...Watch unlikely 

   Valid 040752Z - 040845Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Strong, potentially damaging wind gusts, may accompany
   weak thunderstorm activity likely to spread east of the Blue Ridge
   and across the Greater Washington D.C./Baltimore metropolitan areas
   through 6-7 AM EDT.  It is not clear that a severe weather watch is
   needed, but trends are being monitored.

   DISCUSSION...A narrow line of thunderstorms has shown some
   intensification, near and south of a wave or weak MCV now east of
   Elkins WV.  This activity has been propagating rapidly eastward,
   along and just south of a slow moving or stalling cold front, 
   around 50 kt, which is about the strength of the mean westerly
   deep-layer ambient mean flow across the Allegheny Mountains into
   northern Mid Atlantic.  

   Due to generally weak deep-layer lapse rates, CAPE along this
   corridor is quite weak west of the mountains, but improves somewhat
   (CAPE to 500 J/kg) in better low-level moisture across northern
   Virginia through southern New Jersey.  While some further
   intensification to the east of the Blue Ridge is possible as
   activity rapidly advances eastward through 11-12Z, thunderstorm
   intensities are likely to remain rather modest, based on forecast
   soundings.  However, unsaturated profiles in lower/mid-levels, may
   contribute to evaporative cooling and downward momentum transport of
   rear-inflow, which may undergo some further convective augmentation.

   ..Kerr/Mosier.. 04/04/2025

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

   ATTN...WFO...PHI...AKQ...CTP...LWX...

   LAT...LON   39897751 39677548 38737539 38497760 38557915 39397855
               39897751 

   MOST PROBABLE PEAK WIND GUST...55-70 MPH

[Eskimo Joe]

Holy elevated convection batman.

[WxUSAF]

6 hours ago, high risk said:

          Based on the 00Z suite,  late night convection is pretty certain for areas along and north of I-70.   Whether any of it makes it south towards the lower parts of Howard and Montgomery is less clear.

No thunder yet but some decent wind gusts. Point for the hrrr…it saw this coming yesterday.

[weatherCCB]

Few showers here.    No thunder. 
71/67

[weatherCCB]

Spoke too soon.  House rattling thunder.

[mappy]

7 minutes ago, WxUSAF said:

No thunder yet but some decent wind gusts. Point for the hrrr…it saw this coming yesterday.

Thundered here not long ago. Woke the kid up, who crawled into bed with me lol

[WxUSAF]

Just got one rumble…

[09-10 analogy]

Three flashes, two rumbles. Kind of a kayfabe thunderstorm. 

[aldie 22]

A few rumbles and two periods of heavy rain. 

[BlizzardNole]

Some rolling thunder and very light rain

[high risk]

Enjoyed the thunder and was surprised by a modest gust front, as I expected a more stable surface layer which would have prevented any downward mixing.  But temperatures as the storms arrived were notably warmer than progged, so the storms may have actually been (barely) surface-based.   Super disappointed in the rainfall, but the line really collapsed as it approached the 95 corridor. 

[WxUSAF]

17 minutes ago, high risk said:

Enjoyed the thunder and was surprised by a modest gust front, as I expected a more stable surface layer which would have prevented any downward mixing.  But temperatures as the storms arrived were notably warmer than progged, so the storms may have actually been (barely) surface-based.   Super disappointed in the rainfall, but the line really collapsed as it approached the 95 corridor. 

Yeah maybe didn’t even get 0.1”?

[Kmlwx]

I hit my goal of being awoken by thunder! All things considered that was a decent line. 

Sunday looks like it has some low end potential and then we seemingly get shutout for a block of time. No real long range threats I'm seeing. 

[mappy]

6 hours ago, WxUSAF said:

Yeah maybe didn’t even get 0.1”?

That sucks, almost an inch here this morning

[yoda]

7 hours ago, Kmlwx said:

I hit my goal of being awoken by thunder! All things considered that was a decent line. 

Sunday looks like it has some low end potential and then we seemingly get shutout for a block of time. No real long range threats I'm seeing. 

Looks like maybe a sneaky threat tomorrow... more out west though

[Eskimo Joe]

HRRR was right. Never discount an impulse riding along a front.

 

[high risk]

6 hours ago, yoda said:

Looks like maybe a sneaky threat tomorrow... more out west though

       Yeah, going to be a significant temperature gradient across the area, with a lot of model variation about how the thermal boundaries set up.    Convection seems likely along the boundary later in the day - not seeing forecast soundings that impress me, but I suppose that an isolated severe event can't be totally ruled out.      Looking forward to the potential for more early morning rumbling tonight, though.   

[yoda]

Updated morning discussion from LWX suggests some interest later

While some showers may spill across the mountains during the
late morning and early afternoon, overall this should be a
period of less precipitation in the forecast area. While the
bulk of convection will again be west of the area, heights begin
falling by late afternoon, and the moist conveyor belt begins to
shift back to the southeast. Instability will be able to build
south of the warm front. It appears the best overlap of these
features will be the northwest corner of the forecast area,
resulting in the highest chance of showers and thunderstorms.
Instability is forecast to be on the lower side...however, there
is enough shear for any stronger updrafts to organize and become
capable of producing severe weather. All hazards could be on the
table, especially if there is a supercell or two. There is a
narrow corridor of overlap with 500-1000 J/kg MLCAPE and 300+
m2/s2 SRH this evening between US-50 and I-70. North of this
area, it should remain stable enough to preclude surface-based
convection with a lower severe threat overall; further to the
south and east, less forcing and more mid-level dry air should
keep convective coverage at bay. Aside from somewhat amorphous
forcing and the relatively narrow corridor of favorable overlap
in the parameter space, low-level CAPE may be on the low side
unless more cloud breaks develop. If more cloud breaks are
observed and surface heating is more efficient, higher low-level
instability could raise the threat of severe/rotating storms
this evening in the aforementioned corridor.

[midatlanticweather]

Getting some interesting looking convection firing. 

[batmanbrad]

might have been a "false alarm", but I was getting a TVS on the cell NW of Leesburg on RadarScope for a bit, but it seems to have disappeared.

[87storms]

might have been a "false alarm", but I was getting a TVS on the cell NW of Leesburg on RadarScope for a bit, but it seems to have disappeared.

Warning from that same batch moving into eastern Frederick county. Only had rain here, but they were fattie drops.

[Amped]

Not the radar I was expecting at 59 degrees

[Kmlwx]

CFS monthly over on TropicalTidbits shows a ridge west of the center of the country and neutral heights near us for June. I was looking for signs of any potential "ring of fire" pattern - but I'd think that map would put the ridge axis way too far west for that. Though - we'd avoid big HEAT if that were to come true. Then in the July panel it pushes the ridge axis even farther west...not giving it much though - but that would really keep the summer from getting into the baking oven style heat locally....

With the heavy smoothing on super long range progs like that, though - I'd extrapolate that there would be some severe potential whenever transient ridging gives way to an incoming shortwave/storm system. So while it might not be a 2012 derecho-style pattern....it could be a setup for a weekly squall line/front. 

 

[ravensrule]

6 hours ago, Kmlwx said:

CFS monthly over on TropicalTidbits shows a ridge west of the center of the country and neutral heights near us for June. I was looking for signs of any potential "ring of fire" pattern - but I'd think that map would put the ridge axis way too far west for that. Though - we'd avoid big head if that were to come true. Then in the July panel it pushes the ridge axis even farther west...not giving it much though - but that would really keep the summer from getting into the baking oven style heat locally....

With the heavy smoothing on super long range progs like that, though - I'd extrapolate that there would be some severe potential whenever transient ridging gives way to an incoming shortwave/storm system. So while it might not be a 2012 derecho-style pattern....it could be a setup for a weekly squall line/front. 

 

You always want to avoid big head. 

[Kmlwx]

1 hour ago, ravensrule said:

You always want to avoid big head. 

 oh good lord the worst typo ever

[Kmlwx]

Reaching here...but Monday would have some small potential if the boundary can get north of us. Doesn't look like it happens on the 6z GFS. But instability is not far away. Dewpoints look pretty meager as well. There's some hint of this potential on the CSU MLP maps as well as the NCAR AI page. 

[Kmlwx]

The 12z GFS looks similar. It's a shame because the GFS is forecasting VERY steep mid-level lapse rates - just the boundary is too close to use. However, sometimes something strong can ride the front. It's worth watching simply because there's not much else on the horizon for now. I do think that some place nearby (probably just to the SW) could be primed for some sort of isolated severe day. 

[Kmlwx]

Not for us (well to our west) but the D4 outlook from SPC. There's an EML plume - shame there isn't better moisture return or warmer temps ahead of it. 

...DISCUSSION...
   ...D4/Monday...
   Further amplification of a broadening mid/upper-level trough and
   attendant surface cyclone is expected across the Upper Great Lakes
   to the southern ON/QC border area. Poleward moisture quality from
   the western Gulf will remain sub-optimal, but will continue to 
   improve beneath a lobe of the southern Great Plains EML. The
   northeast extent of weak surface buoyancy should overspread the OH
   Valley by Monday afternoon. This portion of the front will coincide
   with robust 700-500 mb southwesterlies, yielding potential for
   fast-moving convection. Guidance consensus suggests this will remain
   the favored corridor for at least a damaging wind threat.