Alert archive / Delaware / Flash Flood Warnings in 2019

Flash Flood Warning 34, NWS Philadelphia/Mount Holly

June 28, 2019New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this flash flood warning at Jun 28, 2019, 6:15 PM EDT for New Castle County, Delaware. It was in force for 106 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
Jun 28, 2019, 6:15 PM EDT (22:15 UTC)
Expired
Jun 28, 2019, 8:01 PM EDT
In force
106 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County New Castle County, DE

The radar

The Dover AFB radar (KDOX), 97 km from the middle of the area, began a volume at 22:17 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 12:00Z, 10.3 hours before the alert went out and 174 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 12:00Z on 2019-06-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 92 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 12:00Z on 2019-06-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -3 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
92 J/kg
Mixed-layer CIN
-173 J/kg
Mixed-layer LCL
1515 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
-3 m²/s²
0-3 km storm-relative helicity
36 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

328 
WGUS51 KPHI 282215
FFWPHI
DEC003-290015-
/O.NEW.KPHI.FF.W.0034.190628T2215Z-190629T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
615 PM EDT Fri Jun 28 2019

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Northern New Castle County in northern Delaware...

* Until 815 PM EDT.

* At 610 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the northern portions of the county. Flash 
  flooding is expected to begin shortly in the areas of heaviest 
  rain. Flooded roadways will be the main threat.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3971 7578 3980 7569 3980 7555 3977 7545
      3971 7550 3972 7552 3967 7555 3965 7559
      3962 7557 3964 7560 3963 7561 3958 7560
      3958 7578

$$

JJM
2 follow-up statements
700 
WGUS71 KPHI 282251
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
651 PM EDT Fri Jun 28 2019

DEC003-290015-
/O.CON.KPHI.FF.W.0034.000000T0000Z-190629T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-
651 PM EDT Fri Jun 28 2019

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM EDT FOR
NORTHWESTERN NEW CASTLE COUNTY...

At 649 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area have moved east.  However, water remains 
ponded in some areas, so the Flash Flood Warning will remain in 
effect until this water drains. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3973 7575 3975 7568 3974 7565 3965 7565
      3965 7576

$$

JJM
305 
WGUS71 KPHI 290001
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
801 PM EDT Fri Jun 28 2019

DEC003-290010-
/O.CAN.KPHI.FF.W.0034.000000T0000Z-190629T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-
801 PM EDT Fri Jun 28 2019

...THE FLASH FLOOD WARNING FOR NORTHWESTERN NEW CASTLE COUNTY IS
CANCELLED...

The heavy rain has ended and flood waters on roadways and in poor 
drainage areas are receding. Please continue to heed any remaining 
road closures.

LAT...LON 3973 7575 3975 7568 3974 7565 3965 7565
      3965 7576

$$

JJM

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 28, 3:04 PM EDTSpecial Weather StatementPHISussex26 min
Jun 28, 3:51 PM EDTSpecial Weather StatementPHISussex24 min
Jun 28, 4:39 PM EDTSpecial Weather StatementPHIKent36 min
Jun 28, 5:37 PM EDTSpecial Weather StatementPHINew Castle23 min
Jun 28, 6:00 PM EDTSevere Thunderstorm WarningPHINew Castle33 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.