Alert archive / Delaware / Flash Flood Warnings in 2023

Flash Flood Warning 89, NWS Philadelphia/Mount Holly

September 13, 2023Kent County, Delaware

NWS Philadelphia/Mount Holly issued this flash flood warning at Sep 13, 2023, 2:12 AM EDT for Kent County, Delaware. It was in force for 3 hr. 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: Sep 13, 2023, 2:12 AM EDT (06:12 UTC)
Expired: Sep 13, 2023, 5:08 AM EDT
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

County Kent County, DE

The radar

The Dover AFB radar (KDOX), 47 km from the middle of the area, began a volume at 06:12 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
Sep 13, 5:00 AM EDT	RAIN 2	2 Ene Hazlettville, DE	Cocorahs station DE-KN-9 Dover 5.1 WSW.

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

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 6.2 hours before the alert went out and 146 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: 660 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 1174 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 15 m²/s²
0-3 km storm-relative helicity: 25 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

076 
WGUS51 KPHI 130612
FFWPHI
DEC001-131015-
/O.NEW.KPHI.FF.W.0089.230913T0612Z-230913T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
212 AM EDT Wed Sep 13 2023

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Kent County in central Delaware...

* Until 615 AM EDT.

* At 212 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is already occurring.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flooding of small creeks and streams, urban areas,
           highways, streets, and underpasses as well as other
           drainage and low lying areas.

* Some locations that may experience flash flooding include...
  Dover, Smyrna, Camden, Clayton, Cheswold, Bowers, Woodside, Viola, 
  Hartly, Dover Speedway, Rising Sun, and Rising Sun-Lebanon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

Motorists should not attempt to drive around barricades or drive 
cars through flooded areas.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3918 7575 3922 7575 3931 7560 3931 7557
      3933 7557 3940 7544 3939 7543 3906 7537
      3892 7573

FLASH FLOOD...RADAR INDICATED

$$

MPS

2 follow-up statements

007 
WGUS71 KPHI 130746
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
346 AM EDT Wed Sep 13 2023

DEC001-131015-
/O.CON.KPHI.FF.W.0089.000000T0000Z-230913T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kent DE-
346 AM EDT Wed Sep 13 2023

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 615 AM EDT THIS 
MORNING FOR KENT COUNTY...

At 346 AM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 3 inches of rain have 
fallen. Flash flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flooding of small creeks and streams, urban areas,
         highways, streets, and underpasses as well as other
         drainage and low lying areas.

Some locations that may experience flash flooding include...
  Dover, Smyrna, Camden, Clayton, Cheswold, Bowers, Woodside, Viola, 
  Hartly, Dover Speedway, Rising Sun, and Rising Sun-Lebanon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the 
dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 3918 7575 3922 7575 3931 7560 3931 7557
      3933 7557 3940 7544 3939 7543 3906 7537
      3892 7573

FLASH FLOOD...RADAR INDICATED

$$

MPS

934 
WGUS71 KPHI 130908
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
508 AM EDT Wed Sep 13 2023

DEC001-130918-
/O.CAN.KPHI.FF.W.0089.000000T0000Z-230913T1015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kent DE-
508 AM EDT Wed Sep 13 2023

...FLASH FLOOD WARNING IS CANCELLED FOR KENT COUNTY...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat.

A Flood Watch remains in effect until 500 PM EDT Wednesday for 
portions of northern Delaware...New Jersey...and Pennsylvania.

LAT...LON 3918 7575 3922 7575 3931 7560 3931 7557
      3933 7557 3940 7544 3939 7543 3906 7537
      3892 7573

$$

MPS

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 13, 12:49 AM EDT	Severe Thunderstorm Warning	PHI	Kent, New Castle	26 min
Sep 13, 1:15 AM EDT	Special Weather Statement	PHI	New Castle	30 min
Sep 13, 1:45 AM EDT	Severe Thunderstorm Warning	PHI	Kent	45 min
Sep 13, 2:21 AM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	25 min
Sep 13, 2:34 AM EDT	Special Weather Statement	PHI	Kent	26 min
Sep 13, 2:58 AM EDT	Special Weather Statement	PHI	Sussex	32 min
Sep 13, 3:37 AM EDT	Special Weather Statement	PHI	Sussex	23 min

Nearby

Flash Flood Warnings in Delaware, 2023 Every flash flood warning 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.