Alert archive / Delaware / Special Weather Statements in 2021

Special Weather Statement, NWS Philadelphia/Mount Holly

September 9, 2021New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this special weather statement at Sep 9, 2021, 12:58 AM EDT for New Castle County, Delaware. It was in force for 32 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
Sep 9, 2021, 12:58 AM EDT (04:58 UTC)
Expired
Sep 9, 2021, 1:30 AM EDT
In force
32 min
Issued by
NWS Philadelphia/Mount Holly
Hail
0.50 in
Wind
40

County New Castle County, DE

The radar

The Dover AFB radar (KDOX), 98 km from the middle of the area, began a volume at 05:01 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 5.0 hours before the alert went out and 178 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-pSkew-T log-p diagram, Washington/Dulle, VA at 00:00Z on 2021-09-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1652 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Washington/Dulle, VA at 00:00Z on 2021-09-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1652 J/kg
Mixed-layer CIN
-18 J/kg
Mixed-layer LCL
1146 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
136 m²/s²
Significant tornado parameter
1.0
Supercell composite
7.0

Open this sounding in Storm Lab

The text

As transmitted.

269 
WWUS81 KPHI 090458
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
1258 AM EDT Thu Sep 9 2021
 
DEZ001-NJZ016-017-PAZ070-090530-
New Castle DE-Salem NJ-Gloucester NJ-Delaware PA-
1258 AM EDT Thu Sep 9 2021

...A strong thunderstorm will impact portions of northern New Castle,
northwestern Salem, west central Gloucester and south central
Delaware Counties through 130 AM EDT...

At 1258 AM EDT, Doppler radar was tracking a strong thunderstorm over
Bear, or near Newark, moving northeast at 35 mph.

HAZARD...Wind gusts up to 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects. Minor damage to outdoor objects is 
         possible.

Locations impacted include...
Wilmington, Newark, Chester, Pennsville, Carneys Point, Elsmere, New
Castle, Penns Grove, Woodstown, Delaware City, Newport, Arden,
Stanton, Glasgow, Bear, Talleyville, Wilmington Manor, Pike Creek,
Beckett and Greenville.

This includes the following highways...
 New Jersey Turnpike near exit 1.
 Interstate 95 in Pennsylvania between mile markers 0 and 2.
 Interstate 95 in Delaware between mile markers 0 and 23.
 Interstate 295 in New Jersey between mile markers 0 and 10.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

&&

LAT...LON 3987 7542 3963 7528 3956 7576 3960 7579
      3970 7579
TIME...MOT...LOC 0458Z 245DEG 32KT 3963 7571 

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

$$

SFJ

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 8, 9:16 PM EDTAreal Flood AdvisoryPHIWarren3 hr
Sep 8, 9:16 PM EDTSpecial Weather StatementPHISussex, Warren29 min
Sep 8, 9:43 PM EDTSpecial Weather StatementPHISussex, Warren47 min
Sep 8, 10:42 PM EDTFlash Flood WarningPHIWarren6 hr
Sep 8, 10:56 PM EDTSpecial Weather StatementPHIWarren34 min
Sep 8, 11:27 PM EDTSevere Thunderstorm WarningPHIHunterdon, Warren48 min
Sep 8, 11:30 PM EDTAreal Flood AdvisoryPHIMorris, Sussex4 hr
Sep 9, 12:07 AM EDTSpecial Weather StatementPHIHunterdon, Somerset, Warren23 min
Sep 9, 12:18 AM EDTSpecial Marine WarningPHI57 min
Sep 9, 12:30 AM EDTSpecial Weather StatementPHIMorris30 min
Sep 9, 12:41 AM EDTSpecial Marine WarningPHI52 min
Sep 9, 2:17 AM EDTSpecial Weather StatementPHIOcean28 min
Sep 9, 2:46 AM EDTSpecial Weather StatementPHIAtlantic29 min
Sep 9, 3:14 AM EDTSpecial Weather StatementPHIAtlantic31 min
Sep 9, 3:30 AM EDTAreal Flood AdvisoryPHIAtlantic, Burlington, Cape May, Cumberland112 min
Sep 9, 4:28 AM EDTAreal Flood WarningPHIWarren4 hr
Sep 8, 8:47 PM EDTSpecial Weather StatementPHINorthampton28 min
Sep 8, 9:12 PM EDTSpecial Weather StatementPHILehigh48 min
Sep 8, 9:38 PM EDTSpecial Weather StatementPHIBerks52 min
Sep 8, 9:46 PM EDTSpecial Weather StatementPHILehigh, Northampton44 min
Sep 8, 9:48 PM EDTFlash Flood WarningPHILehigh, Northampton7 hr
Sep 8, 9:59 PM EDTAreal Flood AdvisoryPHIBerks3 hr
Sep 8, 10:11 PM EDTSevere Thunderstorm WarningPHIBerks49 min
Sep 8, 10:23 PM EDTTornado WarningPHIBerks22 min
Sep 8, 10:27 PM EDTSpecial Weather StatementPHINorthampton33 min
Sep 8, 10:47 PM EDTAreal Flood AdvisoryPHICarbon, Monroe3 hr
Sep 8, 10:47 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh, Montgomery, Northampton58 min
Sep 8, 11:35 PM EDTSpecial Weather StatementPHIChester, Delaware, Montgomery40 min
Sep 9, 12:08 AM EDTSpecial Weather StatementPHIBucks, Delaware, Montgomery, Philadelphia37 min
Sep 9, 4:26 AM EDTAreal Flood WarningPHILehigh, Northampton3 hr
Sep 9, 1:12 AM EDTAreal Flood AdvisoryPHINew Castle62 min
Sep 9, 5:37 AM EDTAreal Flood AdvisoryPHIKent, New Castle, Sussex3 hr

Nearby

Special Weather Statements in Delaware, 2021Every special weather statement 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.