Alert archive / Delaware / Flash Flood Warnings in 2026

Flash Flood Warning 66, NWS Philadelphia/Mount Holly

July 27, 2026Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 27, 2026, 5:22 PM EDT for Sussex County, Delaware. It was in force for 2 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: Jul 27, 2026, 5:22 PM EDT (21:22 UTC)
Expired: Jul 27, 2026, 7:28 PM EDT
In force: 2 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), 16 km from the middle of the area, began a volume at 21:24 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
Jul 27, 5:48 PM EDT	FLASH FLOOD	1 E Bridgeville, DE	Video showed several inches of water on Route 13 near Bridgeville. Traffic slowed, but road remained passable.

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

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.4 hours before the alert went out and 159 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: 87 J/kg
Mixed-layer CIN: -53 J/kg
Mixed-layer LCL: 1233 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 5 m²/s²
0-3 km storm-relative helicity: 45 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

404 
WGUS51 KPHI 272122
FFWPHI
DEC005-280130-
/O.NEW.KPHI.FF.W.0066.260727T2122Z-260728T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
522 PM EDT Mon Jul 27 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  West Central Sussex County in southern Delaware...

* Until 930 PM EDT.

* At 522 PM EDT, gauge reports indicated thunderstorms producing 
  heavy rain across the warned area. Between 3 and 4 inches of rain 
  have fallen. The expected rainfall rate is 2 to 4 inches in 1 
  hour. Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Gauges reported.

  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...
  Bridgeville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 3870 7554 3870 7565 3875 7570 3880 7564
      3880 7555 3875 7547

FLASH FLOOD...GAUGE INDICATED
EXPECTED RAINFALL RATE...2-4 INCHES IN 1 HOUR

$$

MJL

1 follow-up statement

379 
WGUS71 KPHI 272328
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
728 PM EDT Mon Jul 27 2026

DEC005-272338-
/O.CAN.KPHI.FF.W.0066.000000T0000Z-260728T0130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sussex DE-
728 PM EDT Mon Jul 27 2026

...FLASH FLOOD WARNING IS CANCELLED FOR WEST CENTRAL SUSSEX COUNTY...

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

&&

LAT...LON 3870 7554 3870 7565 3875 7570 3880 7564
      3880 7555 3875 7547

$$

MJL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 27, 2:15 PM EDT	Flood Watch	PHI	New Castle	38 hr
Jul 27, 3:31 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	44 min
Jul 27, 4:14 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	46 min
Jul 27, 4:56 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	20 min

Nearby

Flash Flood Warnings in Delaware, 2026 Every flash flood warning in 2026

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.