Alert archive / Delaware / Areal Flood Advisories in 2021

Areal Flood Advisory 30, NWS Philadelphia/Mount Holly

June 10, 2021Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this areal flood advisory at Jun 10, 2021, 3:29 PM EDT for Sussex County, Delaware. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Jun 10, 2021, 3:29 PM EDT (19:29 UTC)
Expired
Jun 10, 2021, 6:30 PM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 27 km from the middle of the area, began a volume at 19:33 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 80 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 2021-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 408 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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 2021-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 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
408 J/kg
Mixed-layer CIN
-39 J/kg
Mixed-layer LCL
745 m above ground
0-6 km bulk shear
6 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
5 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

771 
WGUS81 KPHI 101929
FLSPHI

Flood Advisory
National Weather Service Mount Holly NJ
329 PM EDT Thu Jun 10 2021

DEC005-102230-
/O.NEW.KPHI.FA.Y.0030.210610T1929Z-210610T2230Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Sussex DE-
329 PM EDT Thu Jun 10 2021

The National Weather Service in Mount Holly has issued a

* Flood Advisory for...
  Southwestern Sussex County in southern Delaware...

* Until 630 PM EDT.

* At 329 PM EDT, Doppler radar indicated heavy rain due to 
  thunderstorms. Minor flooding is ongoing or expected to begin 
  shortly in the advisory area. Between 2 and 4 inches of rain have 
  fallen in portions of the area. An additional 1 to 2 inches of 
  rain are possible.

* Some locations that will experience flooding include...
  Seaford, Laurel, Bridgeville, Delmar, Blades, and Bethel.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be aware of your surroundings and do not drive on flooded roads.

&&

LAT...LON 3874 7572 3875 7560 3845 7541 3846 7569

$$

JEO

Nearby

Areal Flood Advisories in Delaware, 2021Every areal flood advisory in 2021

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.