Alert archive / Delaware / Flash Flood Warnings in 2019

Flash Flood Warning 82, NWS Philadelphia/Mount Holly

August 19, 2019Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 19, 2019, 3:28 PM EDT for Sussex County, Delaware. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 19, 2019, 3:28 PM EDT (19:28 UTC)
Expired
Aug 19, 2019, 6:03 PM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 45 km from the middle of the area, began a volume at 19:27 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 12:00Z, 7.5 hours before the alert went out and 68 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, Wallops Is Stn, VA at 12:00Z on 2019-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1552 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, Wallops Is Stn, VA at 12:00Z on 2019-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 54 square meters per square second.1939Sfc1 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
1552 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
1081 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
54 m²/s²
0-3 km storm-relative helicity
48 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

863 
WGUS51 KPHI 191928
FFWPHI
DEC005-192330-
/O.NEW.KPHI.FF.W.0082.190819T1928Z-190819T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
328 PM EDT Mon Aug 19 2019

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Southeastern Sussex County in southern Delaware...

* Until 730 PM EDT.

* At 328 PM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Over 
  three inches of rain have already fallen. Flash flooding is 
  expected to begin shortly in the areas of heaviest rain.

* Some locations that could experience flooding include...
  Selbyville, Millville, Long Neck, Ocean View and South Bethany. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3845 7525 3862 7519 3862 7504 3845 7504
      3846 7505 3845 7505

$$

PO
1 follow-up statement
290 
WGUS71 KPHI 192203
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
603 PM EDT Mon Aug 19 2019

DEC005-192212-
/O.CAN.KPHI.FF.W.0082.000000T0000Z-190819T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sussex DE-
603 PM EDT Mon Aug 19 2019

...THE FLASH FLOOD WARNING FOR SOUTHEASTERN SUSSEX COUNTY IS
CANCELLED...

The heavy rain has ended. Flood waters have receded. Flooding is no
longer expected to pose a threat. Please continue to heed any
remaining road closures.

LAT...LON 3845 7525 3862 7519 3862 7504 3845 7504
      3846 7505 3845 7505

$$

JJM

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 12:57 PM EDTSpecial Weather StatementPHISussex48 min
Aug 19, 1:43 PM EDTSpecial Weather StatementPHISussex47 min
Aug 19, 1:56 PM EDTSevere Thunderstorm WarningPHISussex49 min
Aug 19, 2:39 PM EDTAreal Flood AdvisoryPHISussex2 hr
Aug 19, 3:00 PM EDTSevere Thunderstorm WarningPHISussex45 min
Aug 19, 4:40 PM EDTSpecial Weather StatementPHISussex50 min
Aug 19, 4:41 PM EDTSpecial Weather StatementPHIKent49 min
Aug 19, 4:46 PM EDTSevere Thunderstorm WarningPHISussex46 min
Aug 19, 4:52 PM EDTAreal Flood AdvisoryPHISussex68 min

Nearby

Flash Flood Warnings in Delaware, 2019Every flash flood 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.