Alert archive / Delaware / Tornado Warnings in 2023

Tornado Warning 4, NWS Philadelphia/Mount Holly

April 1, 2023New Castle County, Delaware; Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this tornado warning at Apr 1, 2023, 6:33 PM EDT for New Castle County, Delaware; Chester County, Pennsylvania. It was in force for 27 min. 3 reports 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: Apr 1, 2023, 6:33 PM EDT (22:33 UTC)
Expired: Apr 1, 2023, 7:00 PM EDT
In force: 27 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 0.75 in

Counties New Castle County, DE, Chester County, PA

The radar

The Dover AFB radar (KDOX), 112 km from the middle of the area, began a volume at 22:35 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
Apr 1, 6:44 PM EDT	HAIL 0.5	Oxford, PA	REPORT FROM MPING: HALF-INCH (0.50 IN.).
Apr 1, 6:50 PM EDT	TSTM WND DMG	1 Nw Nottingham Manor, DE	NWS STORM SURVEY FOUND SPORADIC STRAIGHT LINE WIND DAMAGE CONTINUING INTO NEW CASTLE COUNTY TO BE NOT ASSOCIATED WITH THE UPSTREAM TORNADO WHICH HAD DISSIPATED IN CECIL COUNTY. TIME ESTIMATED FROM RADAR.
Apr 1, 6:50 PM EDT	TSTM WND DMG	Newark, DE	MULTIPLE TREES INTO HOUSES REPORTED IN NEWARK. TIME ESTIMATED VIA RADAR.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 1, 5:30 PM EDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.6 hours before the alert went out and 152 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 648 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 448 m²/s²
0-3 km storm-relative helicity: 443 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

191 
WFUS51 KPHI 012233
TORPHI
DEC003-PAC029-012300-
/O.NEW.KPHI.TO.W.0004.230401T2233Z-230401T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Mount Holly NJ
633 PM EDT Sat Apr 1 2023

The National Weather Service in Mount Holly NJ has issued a

* Tornado Warning for...
  Northwestern New Castle County in northern Delaware...
  Southwestern Chester County in southeastern Pennsylvania...

* Until 700 PM EDT.
    
* At 633 PM EDT, a severe thunderstorm capable of producing a tornado
  was located over Rising Sun, or 11 miles north of Havre De Grace,
  moving east at 35 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...
  Newark, Oxford, West Grove, Glen Roy, North Star, Landenberg, Mount
  Vernon, Kemblesville, Pike Creek, Hockessin, Avondale, Toughkenamon
  and Brookside.

This includes Interstate 95 in Delaware near mile marker 5.
 
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.

&&

LAT...LON 3974 7612 3973 7610 3974 7610 3976 7606
      3983 7602 3992 7575 3966 7569 3965 7579
      3972 7579 3972 7613
TIME...MOT...LOC 2233Z 256DEG 31KT 3971 7605 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Staarmann

1 follow-up statement

191 
WWUS51 KPHI 012246
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
646 PM EDT Sat Apr 1 2023

DEC003-PAC029-012300-
/O.CON.KPHI.TO.W.0004.000000T0000Z-230401T2300Z/
New Castle DE-Chester PA-
646 PM EDT Sat Apr 1 2023

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 PM EDT FOR
NORTHWESTERN NEW CASTLE AND SOUTH CENTRAL CHESTER COUNTIES...
    
At 646 PM EDT, a severe thunderstorm capable of producing a tornado
was located over Fair Hill, or near Newark, moving east at 35 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...
Newark, West Grove, Kemblesville, North Star, Landenberg, Pike Creek,
Hockessin, Avondale, Toughkenamon and Brookside.

This includes Interstate 95 in Delaware near mile marker 5.
 
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.

&&

LAT...LON 3972 7594 3978 7596 3985 7573 3966 7569
      3965 7579 3972 7579
TIME...MOT...LOC 2246Z 257DEG 32KT 3971 7585 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 1, 5:38 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	37 min
Apr 1, 6:01 PM EDT	Tornado Warning	PHI	Kent, Sussex	29 min
Apr 1, 6:22 PM EDT	Tornado Warning Tornado observed	PHI	Sussex	23 min
Apr 1, 6:39 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Kent, New Castle	51 min
Apr 1, 6:58 PM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	47 min
Apr 1, 7:20 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Kent	40 min
Apr 1, 7:36 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Kent, Sussex	39 min
Apr 1, 7:50 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	40 min
Apr 1, 5:27 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Northampton	48 min
Apr 1, 5:53 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Lehigh, Montgomery, Northampton	67 min
Apr 1, 6:04 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery	56 min
Apr 1, 6:37 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Bucks, Chester, Delaware, Montgomery, Philadelphia	53 min
Apr 1, 6:45 PM EDT	Tornado Warning	PHI	Bucks	30 min
Apr 1, 6:57 PM EDT	Tornado Warning	PHI	Philadelphia	33 min
Apr 1, 7:11 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Philadelphia	64 min

Nearby

Tornado Warnings in Delaware, 2023 Tornado Warnings in Pennsylvania, 2023 Every tornado warning in 2023 Tornadoes in 2023

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.