Jump to content
  • Member Statistics

    17,603
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

2020 Mid-Atlantic Severe Weather - General Thread


Kmlwx
 Share

Recommended Posts

Looking at the 18z long range HRRR and the latest 3km NAM - I'm pretty torn. They don't really have much activity in the area - but they do hint at the possibility for one or two good cells. Seems like our usual type of event where it could be an absolute nothing-event. But that SPC and LWX discussions definitely are conditionally very intriguing. A few days ago I had this pretty much written off. Will come down to our typical question of instability. Would be a lot of fun to track something given how downtrodden a lot of folks are right now with the COVID-19 outbreak. 

Link to comment
Share on other sites

Just had a chance to sit down and look at some of the guidance. ARW, ARW2 and NMM pretty much show nothing for us tomorrow. HRDRPS has some nice looking activity in the 20z time frame...but not sure I'd want to put all my eggs in the HRDRPS. 

We'll probably be stuck with a game time call. 

Link to comment
Share on other sites

Um okay... that escalated quickly in the evening AFD

.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...

Short-term models like the HRRR indicate isold supercell
potential possible especially along and north of Interstates 68
and 70. Even if warm front fails to lift into PA, there appears
to be sufficient elevated instability that supercells could
still produce large to very large hail. Convective initation
remains questionable especially in southern areas where there is
lack of frontal convergence. Isolated to scattered
thunderstorms are still expected in the northern half of the
fcst area.

Link to comment
Share on other sites

The 0z 3km NAM appears (based on 2m temps) to get the wedge hung up a bit. In late March, I would be inclined to believe the wedge will be harder to erode than easier. The diving line is about the Potomac River on that run. Some high parameters in a pocket down near La Plata, Fredericksburg etc. 

That's a very believable scenario for now. If I was looking for severe, I'd rather be down in that area than in my area or certainly not @mappy 's area. Though we all know that playing with boundaries and fronts can be rewarding due to the shear. 

It's going to be a day of low coverage it seems - but if one cell can get rooted and has surface based instability to work with - that discussion is well within the realm of possibilities. Certainly not a widespread svr day. 

  • Like 1
Link to comment
Share on other sites

5 hours ago, yoda said:

@high risk

Pretty decent sounding from the 18z NAM for 21z tomorrow at KIAD, no?

SKT_META__KIAD.thumb.png.db11808e46f8fd5771bae2ecb4f800ff.png

 

             These soundings aren't too bad - wind profiles in the lowest 1 km are a bit weak but still fairly good.    Kmlwx has a good analysis - the problem is that not much guidance shows robust convective development in this area.       The one way we could sneak into a better event is if the NAM nest is correct about the slow progression of the warm front.    If a cell interacted with that boundary, it could get interesting.

  • Like 2
Link to comment
Share on other sites

15 minutes ago, high risk said:

 

             These soundings aren't too bad - wind profiles in the lowest 1 km are a bit weak but still fairly good.    Kmlwx has a good analysis - the problem is that not much guidance shows robust convective development in this area.       The one way we could sneak into a better event is if the NAM nest is correct about the slow progression of the warm front.    If a cell interacted with that boundary, it could get interesting.

That is high praise coming from a tagged met! Thank you! I like to think I've come from one of the biggest weenies here in 2006 (from the Eastern days) to where I am now thanks for folks like you. 

Tomorrow could be really nice for an isolated swath of real estate that gets under a cell. Just not sure there will be more than one or two of them total. 

  • Like 2
Link to comment
Share on other sites

Looks like a there is good amount of shear but pretty weak instability to establish/sustain updrafts. If the warm front clears early enough, and some places can get a few hours of sun with temps in the 70s, might be enough to kick off a few decent cells ahead of the cold front. This is all above my pay grade though lol.

Link to comment
Share on other sites

6 minutes ago, WxUSAF said:

It’s moving toward us quickly. Probably will clear dramatically before 2pm.

Finally back at a computer - have been driving back from PA, to the apartment in Columbia and now at my parent's place down in Colesville. Super foggy for this far into the day. About to pull up surface obs to take a look where it is. 

Link to comment
Share on other sites

Wundermap shows the front pretty clearly. The wedge is very visible. There's a station reading 84 out near Petersburg (can't be right...) but low to mid 70s in that area, 60s and 70s down south of Fredericksburg. Looks like the wedge is running roughly from areas like Hancock, MD south to Winchester and then to Culpeper, over to the Potomac River etc. 

Link to comment
Share on other sites

44 minutes ago, Kmlwx said:

Finally back at a computer - have been driving back from PA, to the apartment in Columbia and now at my parent's place down in Colesville. Super foggy for this far into the day. About to pull up surface obs to take a look where it is. 

Eh maybe not. High clouds are about to clear but wedge is eroding slower. Can see that on satellite last 30mins

Link to comment
Share on other sites

2 minutes ago, WxUSAF said:

Eh maybe not. High clouds are about to clear but wedge is eroding slower. Can see that on satellite last 30mins

Think we'd need a stronger S wind to scour out the wedge. Lots of full sunshine just outside the wedge, though. I could see somebody in western Maryland or the WV panhandle getting a decent cell this afternoon. 

Link to comment
Share on other sites

13 hours ago, George BM said:

A pre-climo NW flow regime w/ potentially steep mid-level lapse rates...

We watch. 

 definitely.    and SPC today mentions the mid-Atlantic for both Wednesday and Thursday.     A quick check of the morning guidance suggests that the timing is off here for good potential on both days, but there is certainly time to adjust the setup.

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...