2021 Mid-Atlantic Severe Weather - General Discussion

[Scraff]

A gusty shower. Woooo storms! Smh. Lol. 

[dailylurker]

Just had some impressive wind gust in the past 15 minutes. I'd estimate 45 mph at least. Not much rain but that wind was pretty cool. I actually hear some more roaring in the distance. Wind isn't done yet.

[vastateofmind]

26 minutes ago, Scraff said:

A gusty shower. Woooo storms! Smh. Lol. 

Surely you have an IPA...or two...to make it more bearable.   

[CAPE]

Sudden wind.

[snowfan]

We excel at post frontal rain. 

[r3w]

We had some gusty 30mph winds here, otherwise lackluster...I DID finally catch a flew glimpses of lightning as it moved out over the water so that's something I guess.
Can't wait til things actually warm up for our area...

[Eskimo Joe]

15 hours ago, high risk said:

      500 j/kg of CAPE will do that....     

Come on now, you know it takes at least 550 j/kg CAPE for things to get rockin'.

[Kmlwx]

Looks like we'll be waiting longer for a legit threat. CIPS isn't enthused on anything really on the extended analogs. Something could sneak up, of course. 

[MN Transplant]

Huh 

 

 

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Baltimore MD/Washington DC
339 PM EDT Wed Mar 31 2021

The National Weather Service in Sterling Virginia has issued a

* Tornado Warning for...
  Southeastern King George County in central Virginia...

* Until 415 PM EDT.
    
* At 339 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near Port Royal, or 8 miles south of King George,
  moving northeast at 30 mph.

[Kmlwx]

Huge swath of the country is lit up on the extended CIPS analogs from last night's 0z runs for the 168hr timeframe. 

[George BM]

I WAS low-key wondering about the steep low-level lapse rates, weak instability and deep northwesterly flow for tomorrow after seeing today's 12z CAMs. Apparently the SPC is low-key watching as well.

...Delmarva/Chesapeake Vicinity...

   Moderate northwesterly deep layer flow is forecast across the region
   as a strong upper low moves offshore the Northeast coast and an
   upper ridge slides slowly eastward across the Midwest. Surface
   dewpoints are forecast to increase into the upper 40s and low 50s
   beneath modest midlevel lapse rates, resulting in weak instability
   during the afternoon and evening. Furthermore, forecast soundings
   show a well-mixed boundary layer developing as temperatures warm
   into the 70s. While severe storms are not expected given weak
   instability, a couple of convective showers and/or storms could
   produce locally strong gusts.

   ..Leitman.. 04/05/2021

[yoda]

Sunday maybe?

 Day 4-8 Convective Outlook  
   NWS Storm Prediction Center Norman OK
   0336 AM CDT Wed Apr 07 2021

   Valid 101200Z - 151200Z

   ...DISCUSSION...
   The potential for organized severe thunderstorms will focus during
   the early part of the extended period.  Medium-range models show a
   mid-level trough moving across the MS Valley Saturday and eastward
   into the central/southern Appalachians on Sunday.  A warm sector
   will likely encompass parts of the northeast Gulf Coast states on
   Saturday with an accompanying severe risk.  Uncertainty remains how
   far north and northeast appreciable instability can develop
   Saturday.  By Sunday, a severe threat could include parts of the
   Carolinas/Mid-Atlantic states depending on the timing/evolution of
   the mid-level trough.  The potential for severe will likely be low
   during the early half of next week despite large model variability
   by this timeframe.

   ..Smith.. 04/07/2021

[Kmlwx]

50 minutes ago, yoda said:

Sunday maybe?

GFS is pretty lackluster on parameters. We'll see. 

[yoda]

9 minutes ago, Kmlwx said:

GFS is pretty lackluster on parameters. We'll see. 

I'm figuring that too... looks like it will be awhile before we see our first real thunderstorms... but SPC mentioned us so I thought I'd post it lol

[Kmlwx]

16 minutes ago, yoda said:

I'm figuring that too... looks like it will be awhile before we see our first real thunderstorms... but SPC mentioned us so I thought I'd post it lol

Something can always sneak up on us (just like snow in winter) but nothing "big" is showing up at this point. CIPS extended analogs don't show any signal for our region either. Late April is probably what we are looking at for now - or even early May. That's not atypical either. La Plata 2002 wasn't until late April. Still early for us. 

[Kmlwx]

LOTS of thunder with this stuff. Long, rolling stuff too. Not bad for a day I expected to yield nothing. 

[high risk]

5 hours ago, Kmlwx said:

LOTS of thunder with this stuff. Long, rolling stuff too. Not bad for a day I expected to yield nothing. 

         That was a nice start to the convective season this afternoon.     As for Sunday, my guess is that we wake up in the morning to a Day 2 MRGL.    Seems quite likely that there will be some storms around later in the day (especially north of DC), and parameters aren't great, there is probably just enough low-level and deep-layer shear to get some decent wind gusts and hail.    This will become a more robust threat if the higher NAM dew points (low 60s) are attained.   

[yoda]

20 minutes ago, high risk said:

         That was a nice start to the convective season this afternoon.     As for Sunday, my guess is that we wake up in the morning to a Day 2 MRGL.    Seems quite likely that there will be some storms around later in the day (especially north of DC), and parameters aren't great, there is probably just enough low-level and deep-layer shear to get some decent wind gusts and hail.    This will become a more robust threat if the higher NAM dew points (low 60s) are attained.   

What about tomorrow?  SW portions of the LWX CWA are in MRGL for tor and wind risk

[yoda]

1 hour ago, high risk said:

         That was a nice start to the convective season this afternoon.     As for Sunday, my guess is that we wake up in the morning to a Day 2 MRGL.    Seems quite likely that there will be some storms around later in the day (especially north of DC), and parameters aren't great, there is probably just enough low-level and deep-layer shear to get some decent wind gusts and hail.    This will become a more robust threat if the higher NAM dew points (low 60s) are attained.   

SPC says no for now in new Day 2

[Kmlwx]

Long range 6z HRRR looked pretty good, actually lol. 

[WeatherShak]

From coastal Alabama this am. Friend camping in Gulf State Park




.

[vastateofmind]

6 hours ago, WeatherShak said:

From coastal Alabama this am. Friend camping in Gulf State Park

Camping in an RV....and not a tent, I hope! Dear Lord, what an ice-bomb.

[Kmlwx]

There's the marginal risk for tomorrow on the 1730z update. 

[vastateofmind]

3 minutes ago, Kmlwx said:

There's the marginal risk for tomorrow on the 1730z update. 

Yeah, was just reading this morning's LWX disco, where they're echoing the conventional thoughts discussed in here the past day or two:

Guidance continues to hint at a line of storms forming east of
the Blue Ridge Sunday afternoon and moving east across the area
with the front. While the potential for the development of
severe storms is there, especially in terms of instability, the
wind field aloft looks marginal at best. Also, the forcing
isn`t all that impressive as the parent low pressure system
becomes cut off as it tracks into the Great Lakes.

[high risk]

14 hours ago, yoda said:

What about tomorrow?  SW portions of the LWX CWA are in MRGL for tor and wind risk

              It's possible, but the threat would be after dark this evening, and most sfc-based instability should be gone by then.

[high risk]

22 minutes ago, Kmlwx said:

There's the marginal risk for tomorrow on the 1730z update. 

        I think it makes sense.     Still come questions about how much heating will occur and whether some of the low-level moisture will get mixed out, but the solutions with the warmer and more moist PBLs certainly suggest scattered strong storms during the afternoon.

[high risk]

8 hours ago, high risk said:

        I think it makes sense.     Still come questions about how much heating will occur and whether some of the low-level moisture will get mixed out, but the solutions with the warmer and more moist PBLs certainly suggest scattered strong storms during the afternoon.

                My call (as well as LWX's high PoPs) is in big danger now of busting.     Pretty much all of the 00z CAMs now really mix out the moisture Sunday afternoon, and as a result, it's pretty tough to find more than very isolated showers/storms in any of the simulated reflectivity forecasts.

[Kmlwx]

28 minutes ago, high risk said:

                My call (as well as LWX's high PoPs) is in big danger now of busting.     Pretty much all of the 00z CAMs now really mix out the moisture Sunday afternoon, and as a result, it's pretty tough to find more than very isolated showers/storms in any of the simulated reflectivity forecasts.

The ARW and NMMs have both been super paltry on sim reflectivity for multiple runs now. There was really only one long range HRRR run and one NAM nest run that got good storms into the area. Meh. 

[high risk]

30 minutes ago, Kmlwx said:

The ARW and NMMs have both been super paltry on sim reflectivity for multiple runs now. There was really only one long range HRRR run and one NAM nest run that got good storms into the area. Meh. 

          Good point, although the lack of storms in the ARW is due to it dropping our dew points tomorrow afternoon into the 40s which has seemed really implausible to me.    Regardless of the magnitude, it certainly seems now like dew points will drop during peak heating tomorrow.

[George BM]

I'm actually more interested in the meso-low in southwestern VA now than I am about any potential afternoon convection for the reasons stated above. Perhaps early morning downpours w/ something a little more (gusty winds). If there were a little bit more surface CAPE, it could be more interesting.