Alert archive / Delaware / Areal Flood Warnings in 2018

Areal Flood Warning 21, NWS Philadelphia/Mount Holly

May 19, 2018Kent County, Delaware; Caroline County, Maryland

NWS Philadelphia/Mount Holly issued this areal flood warning at May 19, 2018, 8:41 PM EDT for Kent County, Delaware; Caroline County, Maryland. It was in force for 21 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
May 19, 2018, 8:41 PM EDT (00:41 UTC)
Expired
May 20, 2018, 5:30 PM EDT
In force
21 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Kent County, DE, Caroline County, MD

The radar

The Dover AFB radar (KDOX), 33 km from the middle of the area, began a volume at 00:45 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 00:00Z, 0.7 hours before the alert went out and 121 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 00:00Z on 2018-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 83 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 00:00Z on 2018-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 square meters per square second.193958Sfc1 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
83 J/kg
Mixed-layer CIN
-36 J/kg
Mixed-layer LCL
727 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

805 
WGUS41 KPHI 200041
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
841 PM EDT SAT MAY 19 2018

DEC001-MDC011-201230-
/O.NEW.KPHI.FA.W.0021.180520T0041Z-180520T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kent DE-Caroline MD-
841 PM EDT SAT MAY 19 2018

The National Weather Service in Mount Holly NJ has issued a

* Flood Warning for...
  West central Kent County in central Delaware...
  Northeastern Caroline County in eastern Maryland...

* Until 830 AM EDT Sunday.

* At 840 PM EDT, the Greensboro gage along the Choptank River was 
  approaching flood stage, due to 3 to 5 inches of rainfall over the 
  past three days. Minor flooding is expected on the Greensboro 
  Carnival Ground and a few backyards along the river.

* Some locations that could experience flooding include...
  Greensboro, Ridgely, Goldsboro and Sandtown. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, farmland, and other low lying spots.

A Flood Warning means that flooding is imminent or occurring. All
interested parties should take necessary precautions immediately.

&&

LAT...LON 3901 7569 3890 7577 3890 7583 3893 7589
      3904 7580 3905 7573

$$

LF
2 follow-up statements
174 
WGUS41 KPHI 201150
FLWPHI

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Flood Warning
National Weather Service Mount Holly NJ
750 AM EDT SUN MAY 20 2018

DEC001-MDC011-202130-
/O.EXT.KPHI.FA.W.0021.000000T0000Z-180520T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kent DE-Caroline MD-
750 AM EDT SUN MAY 20 2018

The National Weather Service in Mount Holly NJ has extended the

* Flood Warning for...
  West central Kent County in central Delaware...
  Northeastern Caroline County in eastern Maryland...

* Until 530 PM EDT Sunday.

* At 745 AM EDT, minor flooding continued along the upper Choptank 
  River. The flooding was caused by runoff from the heavy rain over 
  the past few days. Minor flooding is expected on the Greensboro 
  Carnival Ground and in a few backyards along the river. The 
  Choptank River should return within its banks by late afternoon.

* Some locations that could experience flooding include...
  Greensboro, Ridgely, Goldsboro and Sandtown. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

This Flood Warning means that minor flooding is occurring.

&&

LAT...LON 3901 7569 3890 7577 3890 7583 3893 7589
      3904 7580 3905 7573

$$

Iovino
927 
WGUS81 KPHI 202127
FLSPHI

Flood Statement
National Weather Service Mount Holly NJ
527 PM EDT SUN MAY 20 2018

DEC001-MDC011-202132-
/O.EXP.KPHI.FA.W.0021.000000T0000Z-180520T2130Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kent DE-Caroline MD-
527 PM EDT SUN MAY 20 2018

...THE FLOOD WARNING WILL EXPIRE AT 530 PM EDT FOR WEST CENTRAL KENT
AND NORTHEASTERN CAROLINE COUNTIES...

River levels at Greensboro along the Choptank River continues to 
recede after cresting early this morning and then falling below 
flood stage late this afternoon.

Flood waters have receded, and are no longer expected to pose a
threat to life or property. Please continue to heed any road
closures.

LAT...LON 3901 7569 3890 7577 3890 7583 3893 7589
      3904 7580 3905 7573

$$

JRK

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 9:27 PM EDTDense Fog AdvisoryPHICecil9 hr

Nearby

Areal Flood Warnings in Delaware, 2018Areal Flood Warnings in Maryland, 2018Every areal 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; radar from the NEXRAD Level II archive.