Alert archive / Maryland / Flash Flood Warnings in 2018

Flash Flood Warning 41, NWS Philadelphia/Mount Holly

July 24, 20184 counties in Maryland; Kent County, New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 24, 2018, 3:24 AM EDT for 4 counties in Maryland; Kent County, New Castle 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: Jul 24, 2018, 3:24 AM EDT (07:24 UTC)
Expired: Jul 24, 2018, 6:30 AM EDT
In force: 3 hr
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

Counties Kent County, DE, New Castle County, DE, Caroline County, MD, Cecil County, MD, Kent County, MD, Queen Anne's County, MD

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 7.4 hours before the alert went out and 150 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: 791 J/kg
Mixed-layer CIN: -4 J/kg
Mixed-layer LCL: 722 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 141 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 4.2

Open this sounding in Storm Lab

The text

As transmitted.

313 
WGUS51 KPHI 240724
FFWPHI
DEC001-003-MDC011-015-029-035-241130-
/O.NEW.KPHI.FF.W.0041.180724T0724Z-180724T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
324 AM EDT TUE JUL 24 2018

The National Weather Service in Mount Holly NJ has issued a

* Flash Flood Warning for...
  Southwestern New Castle County in northern Delaware...
  Northwestern Kent County in central Delaware...
  Northeastern Queen Anne's County in northeastern Maryland...
  Northeastern Caroline County in eastern Maryland...
  Northeastern Kent County in northeastern Maryland...
  Southeastern Cecil County in northeastern Maryland...

* Until 730 AM EDT.

* At 323 AM EDT, Doppler radar indicated heavy rain across the 
  warned area. Rainfall rates of up to 2 inches per hour are 
  occurring in the heaviest of the rain. Flash flooding is expected 
  to begin shortly in the areas of heaviest rain.

* Some locations that could experience flooding include...
  Dover, Smyrna, Camden, Clayton, Cheswold, Church Hill, Cecilton,
  Millington, Sudlersville, Goldsboro, Woodside, Viola, Hartly,
  Warwick, Hazlettville, Delaney Corner, Crumpton, Sandtown,
  Sassafras and Green Spring.

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.

Please report flooding to your local law enforcement agency when you
can do so safely.

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 3943 7551 3902 7555 3902 7599 3942 7597

$$

MPS

1 follow-up statement

180 
WGUS71 KPHI 241030
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
630 AM EDT TUE JUL 24 2018

DEC001-003-MDC011-015-029-035-241040-
/O.CAN.KPHI.FF.W.0041.000000T0000Z-180724T1130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Kent DE-Queen Anne's MD-Caroline MD-Kent MD-Cecil MD-
630 AM EDT TUE JUL 24 2018

...THE FLASH FLOOD WARNING FOR SOUTHWESTERN NEW CASTLE...NORTHWESTERN
KENT...NORTHEASTERN QUEEN ANNE'S...NORTHEASTERN CAROLINE...
NORTHEASTERN KENT AND SOUTHEASTERN CECIL COUNTIES IS CANCELLED...

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

LAT...LON 3943 7551 3902 7555 3902 7599 3942 7597

$$

MPS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 24, 12:56 AM EDT	Areal Flood Advisory	PHI	Cecil, Kent	4 hr
Jul 24, 3:03 AM EDT	Areal Flood Advisory	PHI	Caroline, Cecil, Kent, Queen Anne's, Talbot	3 hr
Jul 24, 4:56 AM EDT	Areal Flood Advisory	PHI	Cecil, Kent	4 hr
Jul 24, 10:31 AM EDT	Areal Flood Advisory	PHI	Caroline, Kent, Queen Anne's, Talbot	3 hr
Jul 24, 12:45 PM EDT	Special Weather Statement	PHI	Caroline	30 min
Jul 24, 12:50 PM EDT	Areal Flood Advisory	PHI	Cecil, Kent, Queen Anne's	3 hr
Jul 23, 9:14 PM EDT	Rip Current Statement	PHI	Sussex	48 hr

Nearby

Flash Flood Warnings in Maryland, 2018 Flash Flood Warnings in Delaware, 2018 Every flash flood warning in 2018

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.