Alert archive / Maryland / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 303, NWS Philadelphia/Mount Holly

August 1, 2019Cecil County, Maryland

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 1, 2019, 4:02 PM EDT for Cecil County, Maryland. It was in force for 45 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 1, 2019, 4:02 PM EDT (20:02 UTC)
Expired: Aug 1, 2019, 4:47 PM EDT
In force: 45 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Cecil County, MD

The radar

The Dover AFB radar (KDOX), 104 km from the middle of the area, began a volume at 20:06 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Aug 1, 4:16 PM EDT	HAIL 0.25	1 Nw Conowingo, MD	PEA SIZE HAIL REPORTED. MPING REPORT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.0 hours before the alert went out and 139 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 353 J/kg
Mixed-layer CIN: -134 J/kg
Mixed-layer LCL: 1030 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 23 m²/s²
0-3 km storm-relative helicity: 53 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

312 
WUUS51 KPHI 012002
SVRPHI
MDC015-012100-
/O.NEW.KPHI.SV.W.0303.190801T2002Z-190801T2100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
402 PM EDT Thu Aug 1 2019

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northern Cecil County in northeastern Maryland...

* Until 500 PM EDT.

* At 402 PM EDT, a severe thunderstorm was located over Rock Springs,
  or 12 miles north of Havre De Grace, moving southeast at 15 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...
  Elkton, Calvert, North East, Rising Sun, Charlestown, Zion, Blake,
  Lombard, Richardsmere, Woodlawn, West Nottingham, Octoraro,
  Pleasant Hill, Conowingo, Rock Springs, Bay View, Farmington,
  Perryville and Port Deposit.

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.

&&

LAT...LON 3972 7591 3954 7583 3952 7598 3955 7603
      3955 7608 3963 7615 3965 7616 3968 7621
      3972 7623
TIME...MOT...LOC 2002Z 337DEG 12KT 3972 7615 

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

Gorse

2 follow-up statements

597 
WWUS51 KPHI 012023
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
423 PM EDT Thu Aug 1 2019

MDC015-012100-
/O.CON.KPHI.SV.W.0303.000000T0000Z-190801T2100Z/
Cecil MD-
423 PM EDT Thu Aug 1 2019

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 500 PM EDT
FOR NORTHERN CECIL COUNTY...

At 423 PM EDT, a severe thunderstorm was located over Rock Springs,
or 11 miles north of Havre De Grace, moving south 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...
Elkton, Calvert, North East, Rising Sun, Charlestown, Zion, Blake,
Lombard, Richardsmere, Woodlawn, West Nottingham, Octoraro, Pleasant
Hill, Conowingo, Rock Springs, Bay View, Farmington, Perryville and
Port Deposit.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent 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.

&&

LAT...LON 3972 7591 3954 7583 3952 7598 3955 7603
      3955 7608 3963 7615 3965 7616 3968 7621
      3972 7623
TIME...MOT...LOC 2023Z 338DEG 9KT 3970 7619 

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

Gorse

748 
WWUS51 KPHI 012047
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
447 PM EDT Thu Aug 1 2019

MDC015-012057-
/O.CAN.KPHI.SV.W.0303.000000T0000Z-190801T2100Z/
Cecil MD-
447 PM EDT Thu Aug 1 2019

...THE SEVERE THUNDERSTORM WARNING FOR NORTHERN CECIL COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore, this warning has been cancelled.

LAT...LON 3972 7591 3954 7583 3952 7598 3955 7603
      3955 7608 3963 7615 3965 7616 3968 7621
      3972 7623
TIME...MOT...LOC 2046Z 337DEG 12KT 3962 7615 

$$

Gorse

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 31, 8:00 PM EDT	Special Weather Statement	PHI	Kent	30 min
Jul 31, 8:13 PM EDT	Special Weather Statement	PHI	Queen Anne's	32 min
Jul 31, 8:47 PM EDT	Special Weather Statement	PHI	Caroline	28 min
Aug 1, 4:06 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Kent, Queen Anne's	54 min
Aug 1, 4:41 PM EDT	Severe Thunderstorm Warning	PHI	Cecil	21 min
Aug 1, 4:56 PM EDT	Severe Thunderstorm Warning	PHI	Caroline, Queen Anne's	50 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2019 Every severe thunderstorm warning in 2019

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.