2019 Mid-Atlantic Severe Wx - General Discussion

[Stormfly]

50 minutes ago, losetoa6 said:

Lots of lightning just to my north . Probably slip to my east . Mappyville towards Harford most likely will see something. 

Seeing the lightning and winds picked up out of the north peaking at just under 30 mph.  No rain and thunder barely audible at this distance.
Went out to check about an hour ago and TBH the most enjoyable thing was the incredible amount of fireflies!  They're everywhere.  Usually don't see these numbers until the last week of June.  Of course last year the latest we saw them was October 7 which in its own was very unusual.  The last time we saw them that late (end of Sept) was 2009.  Was hoping to see a repeat of 09-10 winter but we all know how that went! LOL

Activity seems to be waning.  Pity.  In this area nocturnal storms can be surprisingly intense.  Anyone remember the band that cut through central MD back in 1987?  From up here it looked like WWIII broke out.  And our friends north of York said the lightning was so bright it woke them up.  Those storms were in the Annapolis area.  Very tall anvils.  Sky was clear overhead.  Love how bolts appear to shoot sideways out of those thunderheads and twist like barbed wire.  I was talking to friends that lived in Perry Hall and they couldn't believe how bright the lightning was and thought it was peculiar that there was no thunder.

[yoda]

00z NAM sim radar keeps us dry all day until a bow echo or squall line comes dropping in between 00z and 03z THUR

00z NAM also shows some nice ML Lapse rates in the evening as well 

[yoda]

Both 01z and 02z HRRR at the very end of their runs have storms exploding across the region around 19z

[high risk]

43 minutes ago, yoda said:

Both 01z and 02z HRRR at the very end of their runs have storms exploding across the region around 19z

        Those unimpressive 00z CAM runs were likely outliers.    These recent HRRR runs fit the earlier progs - I'm still in for an enhanced day.      I'm thinking 2% TOR, 15 % HAIL, and 30% WIND on the new Day 1.

[yoda]

1 hour ago, high risk said:

        Those unimpressive 00z CAM runs were likely outliers.    These recent HRRR runs fit the earlier progs - I'm still in for an enhanced day.      I'm thinking 2% TOR, 15 % HAIL, and 30% WIND on the new Day 1.

You sort of win... but its 5/30/30 for N VA and DC and MD into S PA

[Kmlwx]

NAM nest and HRRR pretty much give all the big time stuff to PA...again. Gives us some minor scraps. We do get some better storms tomorrow  - always the next day...

Hopefully we can work on those trends in subsequent runs...

[H2O]

its early.  

[mappy]

16 hours ago, losetoa6 said:

I think there's a thunder shower over your yard now  

missed out on the early stuff, popped up just to my north and went east. but i did get a little from the stuff that came out of PA around 10pm or so. heck of a gust front ahead of it, followed by some T&L and brief, but heavy, rain. it watered the garden, so no complaints. 

16 hours ago, high risk said:

          I don't see tomorrow as a MDT risk day here.    Comparing the supercell parade in PA today, 

                     1)  The overall strength of the wind field in the column will be weaker here tomorrow

                     2)   The low-level shear won't be nearly as strong

                     3)   We are going to be much hotter tomorrow than in PA today, meaning that any supercells will gust out and lead to upscale growth.   I just don't think we'll have a fully discrete mode.

                 There will be SVR around, but the ENH covers the threat pretty well.

i like it. sounds about right given the set up. 

[AfewUniversesBelowNormal]

Sky is bright blue, clear. Yesterday the storms moved in as a "high energy front". I would say the same thing happens today.

[high risk]

6 hours ago, yoda said:

You sort of win... but its 5/30/30 for N VA and DC and MD into S PA

         Thanks!    But I'm tallying this as a loss.    SPC is more aggressive than I am....

[Kmlwx]

Newest HRRR run is a little better - but primary focus still appears to be PA. Will be watching nowcast trends this morning. 

[high risk]

29 minutes ago, Kmlwx said:

Newest HRRR run is a little better - but primary focus still appears to be PA. Will be watching nowcast trends this morning. 

         I think it nicely fits the general idea that the more significant threat will overall stay north of DC.

[Kmlwx]

4 minutes ago, high risk said:

         I think it nicely fits the general idea that the more significant threat will overall stay north of DC.

Frustrating to keep having stuff be north of us. 

[high risk]

4 minutes ago, Kmlwx said:

Frustrating to keep having stuff be north of us. 

   

         Looks like it would be a sharp cutoff for the better stuff, so the Montgomery-Howard corridor could still do quite well.    But yeah, this has been an annoying couple of days.   We actually get into some impressive flow aloft tomorrow, so while instability will be less, it has potential to be better than the MRGL currently shown.

[AfewUniversesBelowNormal]

Getting hot, will probably be some nice storms. 

[frd]

22 minutes ago, high risk said:

Looks like it would be a sharp cutoff for the better stuff, so the Montgomery-Howard corridor could still do quite well.

Looking at the radar over the Midwest at this time and the general complex's movement I would agree that just around DC., and to it's North would be in for the goods later.  And wow to the rainfall potential as well. 

I actually wonder if some rogue storms hit early near and around Baltimore before the main show later.  

[mappy]

If I was able to travel to see better storms, I'd go up to Allentown and hang out there to see what pops. 

[high risk]

   That's one heck of a squall line on the 12z NAM nest.     I'm going to conveniently ignore that the only area where a solid 450 mile line falls apart is Howard and Montgomery Counties.....

[yoda]

3 minutes ago, high risk said:

   That's one heck of a squall line on the 12z NAM nest.     I'm going to conveniently ignore that the only area where a solid 450 mile line falls apart is Howard and Montgomery Counties.....

Also decent SRH(near 200)... so maybe some embedded sups or mesovorticies?

[mappy]

7 minutes ago, high risk said:

   That's one heck of a squall line on the 12z NAM nest.     I'm going to conveniently ignore that the only area where a solid 450 mile line falls apart is Howard and Montgomery Counties.....

ha, you aren't kidding about the line. 

[Eskimo Joe]

Heh, we're already popping ~2,000 SBCAPE at 10:15 am.  

[Eskimo Joe]

ATTN: @yoda

Quote

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1018 AM EDT WED MAY 29 2019

.SYNOPSIS...
A FRONTAL BOUNDARY WILL REMAIN SITUATED NORTH OF THE REGION 
THROUGH THURSDAY BEFORE MIGRATING SOUTHWARD ACROSS THE REGION 
THURSDAY NIGHT. ANOTHER FRONTAL SYSTEM MAY AFFECT THE REGION 
OVER THE WEEKEND. CANADIAN HIGH PRESSURE IS POISED TO SETTLE
OVER THE REGION THROUGH THE EARLY PORTION OF NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
A STATIONARY BOUNDARY RESIDES ACROSS NORTHERN PA THIS MORNING, 
STRETCHING BACK OVER OH/IN, WITH MID-HIGH LEVEL CLOUDS STREAMING
INTO THE AREA FROM WV. THERE ARE A FEW SHOWERS AND ISOLATED
THUNDERSTORMS OVER EASTERN WV, BUT THEY HAVE WEAKENED OVER THE 
LAST COUPLE OF HOURS AS THEY APPROACH THE SOUTHERN PORTION OF 
THE POTOMAC HIGHLANDS. WARM AND HUMID CONDITIONS ARE ENGULFING 
THE AREA THIS MORNING WITH TEMPERATURES IN THE UPPER 70S TO 
LOWER 80S, AND DEWPOINTS ELEVATED IN THE MID-UPPER 60S. MOSTLY 
SUNNY SKIES EXPECTED INTO THIS AFTERNOON AS THE AFOREMENTIONED 
MID TO HIGH CLOUDS CONTINUE STREAMING OVERHEAD. TEMPERATURES 
WILL WARM NICELY ON THE HEELS OF INCREASING SOUTHWESTERLY FLOW,
REACHING THE LOW TO MIDDLE 90S THIS AFTERNOON. GIVEN THE 
MOISTURE IN PLACE, HEAT INDICES WILL BE NEARING THE CENTURY MARK
ACROSS NORTHERN AND CENTRAL VA. 

THE 12Z IAD UPPER AIR SOUNDING SAMPLED A SEASONABLY MOIST 
ATMOSPHERE WITH A PWAT OF 1.27", WITH A CAPPING INVERSION BASED 
AROUND 700MB AND A UNIFORM WEST NORTHWEST FLOW ALOFT. THIS CAP 
MAY INHIBIT THUNDERSTORM DEVELOPMENT INITIALLY THIS AFTERNOON, 
BEFORE EVENTUALLY ERODING. TO GET A BETTER HANDLE ON THE SEVERE 
POTENTIAL LATER THIS AFTERNOON, WE WILL BE RELEASING AN 18Z 
UPPER AIR BALLOON TO SAMPLE THE CURRENT STATE OF THE ATMOSPHERE 
AT THAT TIME. THE CURRENT FORECAST REMAINS ON TRACK WITH NO 
MAJOR CHANGES NEEDED AT THIS TIME.

 

[Kmlwx]

12 minutes ago, high risk said:

   That's one heck of a squall line on the 12z NAM nest.     I'm going to conveniently ignore that the only area where a solid 450 mile line falls apart is Howard and Montgomery Counties.....

Straight out of the weenie handbook. I like it

[Kmlwx]

2 minutes ago, Eskimo Joe said:

Heh, we're already popping ~2,000 SBCAPE at 10:15 am.  

MLCAPE (as usual) is much lower but climbing.

[Eskimo Joe]

2 minutes ago, Kmlwx said:

MLCAPE (as usual) is much lower but climbing.

Always will be.  

[high risk]

17 minutes ago, yoda said:

Also decent SRH(near 200)... so maybe some embedded sups or mesovorticies?

             embedded sups are definitely possible, but with a deep PBL with accompanying inverted-V sounding, it would be really tough to get any rotation down to the ground.

[yoda]

1 minute ago, high risk said:

             embedded sups are definitely possible, but with a deep PBL with accompanying inverted-V sounding, it would be really tough to get any rotation down to the ground.

That makes sense... thanks  

[Kmlwx]

Very soupy out already. Most areas locally are well into the 80s and dewpoints are juicy. 

[yoda]

Just now, Kmlwx said:

Very soupy out already. Most areas locally are well into the 80s and dewpoints are juicy. 

Might be our first day of HX around 100... the AFD mentioned that as well

[Kmlwx]

For laughs - there is a pocket of 30+ supercell composite parameter tomorrow over Central MD. SE surface wind on the sounding I pulled and a NICE looking hodograph. I'm sure it's contaminated.