Alert archive / Delaware / Tornado Warnings in 2021

Tornado Warning 8, NWS Philadelphia/Mount Holly

July 9, 2021Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this tornado warning at Jul 9, 2021, 12:28 AM EDT for Sussex County, Delaware. It was in force for 17 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jul 9, 2021, 12:28 AM EDT (04:28 UTC)
Expired: Jul 9, 2021, 12:45 AM EDT
In force: 17 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.0 in

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 37 km from the middle of the area, began a volume at 04:28 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.

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 4.5 hours before the alert went out and 73 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: 440 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 675 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 151 m²/s²
0-3 km storm-relative helicity: 336 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 3.3

Open this sounding in Storm Lab

The text

As transmitted.

792 
WFUS51 KPHI 090428
TORPHI
DEC005-090515-
/O.NEW.KPHI.TO.W.0008.210709T0428Z-210709T0515Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Mount Holly NJ
1228 AM EDT Fri Jul 9 2021

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Southeastern Sussex County in southern Delaware...

* Until 115 AM EDT.
    
* At 1228 AM EDT, a severe thunderstorm capable of producing a
  tornado was located near Millville, or 10 miles northwest of Ocean
  City, moving north at 45 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* Locations impacted include...
  Millsboro, Selbyville, Dagsboro, Millville, Long Neck, Ocean View,
  Frankford and South Bethany.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

&&

LAT...LON 3863 7534 3870 7526 3869 7512 3846 7504
      3846 7505 3845 7505 3845 7524
TIME...MOT...LOC 0428Z 158DEG 38KT 3850 7516 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

BAH

2 follow-up statements

505 
WWUS51 KPHI 090435
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1235 AM EDT Fri Jul 9 2021

DEC005-090515-
/O.CON.KPHI.TO.W.0008.000000T0000Z-210709T0515Z/
Sussex DE-
1235 AM EDT Fri Jul 9 2021

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 115 AM EDT FOR
SOUTHEASTERN SUSSEX COUNTY...
    
At 1235 AM EDT, a severe thunderstorm capable of producing a tornado
was located near Dagsboro, or 13 miles southeast of Georgetown,
moving north at 40 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

Locations impacted include...
Millsboro, Dagsboro, Millville, Long Neck, Ocean View and Frankford. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

Tornadoes are extremely difficult to see and confirm at night. Do not
wait to see or hear the tornado. TAKE COVER NOW!

&&

LAT...LON 3863 7534 3870 7526 3870 7519 3869 7519
      3869 7515 3852 7511 3850 7521
TIME...MOT...LOC 0435Z 158DEG 38KT 3857 7520 

TORNADO...RADAR INDICATED
HAIL...0.00IN

$$

Deal

785 
WWUS51 KPHI 090445
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
1245 AM EDT Fri Jul 9 2021

DEC005-090455-
/O.CAN.KPHI.TO.W.0008.000000T0000Z-210709T0515Z/
Sussex DE-
1245 AM EDT Fri Jul 9 2021

...THE TORNADO WARNING FOR SOUTHEASTERN SUSSEX COUNTY IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning has been cancelled.  However small hail is
still possible with this thunderstorm.

LAT...LON 3863 7534 3870 7526 3870 7519 3869 7519
      3869 7515 3852 7511 3850 7521
TIME...MOT...LOC 0443Z 158DEG 38KT 3867 7525 

$$

Deal

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 8, 10:19 PM EDT	Areal Flood Advisory	PHI	Kent, Sussex	5 hr
Jul 8, 11:37 PM EDT	Tornado Warning	PHI	Sussex	23 min
Jul 8, 11:59 PM EDT	Tornado Warning	PHI	Sussex	12 min
Jul 9, 12:04 AM EDT	Tornado Warning	PHI	Sussex	26 min
Jul 9, 12:11 AM EDT	Tornado Warning	PHI	Sussex	35 min
Jul 9, 4:54 PM EDT	Special Weather Statement	PHI	New Castle	66 min
Jul 9, 5:17 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	43 min
Jul 9, 6:19 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	41 min
Jul 9, 6:50 PM EDT	Areal Flood Advisory	PHI	New Castle	2 hr
Jul 9, 6:57 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	63 min

Nearby

Tornado Warnings in Delaware, 2021 Every tornado warning in 2021 Tornadoes in 2021

Sources

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