2019 Mid-Atlantic Severe Wx - General Discussion

[EastCoast NPZ]

Line looks healthy.  I see lightning off to my west.

[MetalCapsFan]

That line from the west finally arrived, pouring in B'more, lil bit of lightning, but no wind or thunder as of yet

ETA: coupla mins later lightning flash followed by low rolling thunder but nothing close to severe, will take the rain though

[smokeybandit]

That line died pretty quick on the southern end of it.

[Kmlwx]

3 hours ago, smokeybandit said:

That line died pretty quick on the southern end of it.

Yeah that had been well modeled too from guidance earlier in the day. 

[NorthArlington101]

Good stormy day. Where did this come from?

[NorthArlington101]

Cell N of Middleburg, VA has some broad low level rotation.

[Tater Tot]

Pretty outflow boundary!

[Eskimo Joe]

OT, but check this out

 

[Kmlwx]

1 hour ago, Eskimo Joe said:

OT, but check this out

Satellite indicated! 

[high risk]

Slight risk today.  The CAMs are not in much agreement concerning coverage, but they generally agree on a 4-7pm window.  (HRRR wants to initiate locally around 3pm).    Looks like better coverage in MD than VA.   Shear is not great (it’s lousy on the HRRR), but with the instability, several CAMs show marginal shear for some wind threat.  

[JakkelWx]

Downgrade the slight risk. I'm sure we'll get something that way. 

[George BM]

SEL1

   URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 461
   NWS Storm Prediction Center Norman OK
   1205 PM EDT Sat Jun 29 2019

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     Far northern Delaware
     Far northeast Maryland
     New Jersey
     South-central New York
     Central and eastern Pennsylvania
     Coastal Waters

   * Effective this Saturday afternoon and evening from 1205 PM
     until 700 PM EDT.

   * Primary threats include...
     Scattered damaging wind gusts to 70 mph likely
     Isolated large hail events to 1.5 inches in diameter possible

   SUMMARY...Multiple clusters of thunderstorms will spread east across
   a large portion of Pennsylvania and adjacent states through early
   evening. Embedded strong wind gusts producing damage will be the
   primary hazard.

   The severe thunderstorm watch area is approximately along and 95
   statute miles north and south of a line from 35 miles west northwest
   of State College PA to 20 miles south southeast of Newark NJ. For a
   complete depiction of the watch see the associated watch outline
   update (WOUS64 KWNS WOU1).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 460...

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
   few cumulonimbi with maximum tops to 500. Mean storm motion vector
   28025.

 

[frd]

Storms on the move SE already from NW and Central PA. 

 

 

 

[George BM]

3 minutes ago, frd said:

Storms on the move SE already from NW and Central PA. 

 

 

 

There is some decent mlcape and low-level lapse rates as well as of 16z.

[JakkelWx]

4,000 J/kg of SBCAPE already and 2,000 MLCAPE. Whole area should be under a watch.

[frd]

1 minute ago, JakkelWx said:

4,000 J/kg of SBCAPE already and 2,000 MLCAPE. Whole area should be under a watch.

Seems severe hail today is a moderate risk. 

 

3 minutes ago, JakkelWx said:

4,000 J/kg of SBCAPE already and 2,000 MLCAPE. Whole area should be under a watch.

On the  link here 

https://www.spc.noaa.gov/products/watch/ww0461.html

Do you know the difference in the table under risks ?  The SPC mentions a moderate risk for severe hail, and a low risk for 2 inch plus hail. What defines severe hail ? 

 

 

 

[JakkelWx]

Just now, frd said:

Seems severe hail today is a moderate risk. 

 

On the  link here 

https://www.spc.noaa.gov/products/watch/ww0461.html

Do you know the difference in the table under risks ?  The SPC mentions a moderate risk for severe hail, and a low risk for 2 inch plus hail. What defines severe hail ? 

 

 

 

Severe hail is hail that meets criteria for severe warning. 1 inch hail or greater is severe.

[George BM]

1 minute ago, frd said:

Seems severe hail today is a moderate risk. 

 

On the  link here 

https://www.spc.noaa.gov/products/watch/ww0461.html

Do you know the difference in the table under risks ?  The SPC mentions a moderate risk for severe hail, and a low risk for 2 inch plus hail. What defines severe hail ? 

 

 

 

Hail 1"+ in diameter (quarter sized or greater)

[JakkelWx]

STW for the anvil cloud I saw developing earlier now.

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM EDT
FOR NORTHERN KENT AND SOUTHEASTERN CECIL COUNTIES...

At 144 PM EDT, a severe thunderstorm was located near Hollywood
Beach, or 9 miles east of Aberdeen Proving Ground, moving southeast
at 10 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Minor damage to vehicles is possible. Wind damage to roofs,
         siding, trees, and power lines is possible.

Locations impacted include...
Cecilton, Warwick, Bohemias Mills and Cayots.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature`s leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3940 7600 3943 7600 3946 7601 3951 7598
      3948 7578 3942 7577 3934 7583
TIME...MOT...LOC 1744Z 293DEG 7KT 3946 7594

HAIL...1.00IN
WIND...60MPH

[Kmlwx]

HRRR seems to have a comically bad handle on the present convection in PA

[frd]

5 minutes ago, JakkelWx said:

STW for the anvil cloud I saw developing earlier now.

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 215 PM EDT
FOR NORTHERN KENT AND SOUTHEASTERN CECIL COUNTIES...

At 144 PM EDT, a severe thunderstorm was located near Hollywood
Beach, or 9 miles east of Aberdeen Proving Ground, moving southeast
at 10 mph.

That storm, which is to my WSW , not too far really,  is dropping incredible rainfall based on the radar loop .  

[JakkelWx]

Just now, frd said:

That storm, which is to my WSW , not too far really,  is dropping incredible rainfall based on the radar loop .  

Barely moving, too. I bet those rainfall rates are almost 2 inches per hour in that storm.

[frd]

4 minutes ago, JakkelWx said:

Barely moving, too. I bet those rainfall rates are almost 2 inches per hour in that storm.

Right now some sort of boundary setting up on the Eastern Shore ( storms developing along it )  to my West and Northwest far displaced from the line moving Se from PA. A lot of thunder here now. I too saw that anvil you mentioned. Very impressive too watch 

[George BM]

SEL2

   URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 462
   NWS Storm Prediction Center Norman OK
   205 PM EDT Sat Jun 29 2019

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     District Of Columbia
     Delaware
     Maryland
     Northern Virginia
     Eastern West Virginia Panhandle
     Coastal Waters

   * Effective this Saturday afternoon and evening from 205 PM until
     700 PM EDT.

   * Primary threats include...
     Scattered damaging wind gusts to 70 mph possible
     Isolated large hail events to 1.5 inches in diameter possible

   SUMMARY...Cluster of strong thunderstorms over south-central
   Pennsylvania may cross into portions of Maryland and Delaware, while
   additional development occurs farther west. Scattered damaging winds
   are the primary threat.

   The severe thunderstorm watch area is approximately along and 40
   statute miles north and south of a line from 35 miles south of
   Hagerstown MD to 25 miles southeast of Dover DE. For a complete
   depiction of the watch see the associated watch outline update
   (WOUS64 KWNS WOU2).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 460...WW 461...

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
   few cumulonimbi with maximum tops to 500. Mean storm motion vector
   29025.

   ...Grams

[Scraff]

That’s the DC storm taken about 15 mins ago from Columbia, MD. Cool stuff!

[jacindc]

Sun already back out after the DC storm, which was fading by the time it got to me on the Hill.

[frd]

Well lets see how the trees and garden makes out. 

I rather not do high winds anymore, surprised this is tracking this way after the downpour already and the air temp is way down.   

 Severe Thunderstorm Warning
DEC003-MDC015-291915-
/O.NEW.KPHI.SV.W.0151.190629T1847Z-190629T1915Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
247 PM EDT Sat Jun 29 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  West central New Castle County in northern Delaware...
  East central Cecil County in northeastern Maryland...

* Until 315 PM EDT.

* At 246 PM EDT, a severe thunderstorm was located over Cayots, or
  near Elkton, and moving east at 5 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Minor damage to vehicles is possible. Wind damage to
           roofs, siding, trees, and power lines is possible.

* Locations impacted include...
  Middletown, Warwick, Mount Pleasant, Cayots, Hollywood Beach,
  Bohemias Mills and Chesapeake City.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

In addition to large hail and damaging winds, frequent cloud to
ground lightning is occurring with this storm. Move indoors
immediately. Remember, if you can hear thunder, you are close enough
to be struck by lightning.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

[JakkelWx]

Awesome CU towers to my east.

[frd]

Well ,that was worth the warning, winds to about 40 maybe 45 , blinding rain in sheets, hail about .75 I think.  Over 1.25 inches of rain in less than 35 minutes 

No tree damage, so thats good but not sure about the garden and the hail , I hope its Ok will look a bit later.  

[Eskimo Joe]

Line in PA gusting out and dying off....