Alert archive / Delaware / Areal Flood Advisories in 2020

Areal Flood Advisory 38, NWS Philadelphia/Mount Holly

June 20, 2020Salem County, New Jersey; Kent County, New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this areal flood advisory at Jun 20, 2020, 12:32 PM EDT for Salem County, New Jersey; Kent County, New Castle County, Delaware. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Jun 20, 2020, 12:32 PM EDT (16:32 UTC)
Expired
Jun 20, 2020, 4:30 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon

Counties Kent County, DE, New Castle County, DE, Salem County, NJ

The radar

The Dover AFB radar (KDOX), 66 km from the middle of the area, began a volume at 16:36 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, 4.5 hours before the alert went out and 166 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 2020-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 961 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 2020-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
961 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
703 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
66 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal flood advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Philadelphia/Mount Holly wrote its last area forecast discussion before this areal flood advisory went out at Jun 20, 10:47 AM EDT, 1 hour 45 minutes earlier.

Area forecast discussion, Jun 20, 10:47 AM EDT, 1 hour 45 minutes before
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Hazardous weather outlook, Jun 20, 11:00 AM EDT, 1 hour 32 minutes before
Hazardous Weather Outlook
National Weather Service Mount Holly NJ
1100 AM EDT Sat Jun 20 2020

DEZ001>003-MDZ008-012-015-019-020-NJZ001-007>010-012-015>019-021-
PAZ054-055-060>062-070-071-101>106-211500-
New Castle-Kent-Inland Sussex-Cecil-Kent MD-Queen Annes-Talbot-
Caroline-Sussex-Warren-Morris-Hunterdon-Somerset-Middlesex-Mercer-
Salem-Gloucester-Camden-Northwestern Burlington-Cumberland-Carbon-
Monroe-Berks-Lehigh-Northampton-Delaware-Philadelphia-
Western Chester-Eastern Chester-Western Montgomery-
Eastern Montgomery-Upper Bucks-Lower Bucks-
1100 AM EDT Sat Jun 20 2020

This Hazardous Weather Outlook is for central Delaware, northern
Delaware, southern Delaware, northeast Maryland, central New
Jersey, northern New Jersey, northwest New Jersey, southern New
Jersey, east central Pennsylvania, northeast Pennsylvania and
southeast Pennsylvania.

.DAY ONE...Today and tonight.

Scattered thunderstorms are expected to develop this afternoon. Some
of the storms may produce locally heavy rainfall, which may lead to
an isolated instance of flash flooding.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

There is a chance of storms daily through at least Wednesday. Some
of the storms may produce locally heavy rainfall, which may lead to
an isolated instance of flash flooding.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

DEZ004-NJZ014-024>026-211500-
Delaware Beaches-Eastern Monmouth-Atlantic Coastal Cape May-
Coastal Atlantic-Coastal Ocean-
1100 AM EDT Sat Jun 20 2020

This Hazardous Weather Outlook is for southern Delaware, central
New Jersey and southern New Jersey.

.DAY ONE...Today and tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

There is a chance of storms daily through at least Wednesday. Some
of the storms may produce locally heavy rainfall, which may lead to
an isolated instance of flash flooding.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

ANZ430-431-450>455-211500-
Delaware Bay waters north of East Point NJ to Slaughter Beach DE-
Delaware Bay waters south of East Point NJ to Slaughter Beach DE-
Coastal waters from Sandy Hook to Manasquan Inlet NJ out 20 nm-
Coastal waters from Manasquan Inlet to Little Egg Inlet NJ out 20 nm-
Coastal waters from Little Egg Inlet to Great Egg Inlet NJ out 20 nm-
Coastal waters from Great Egg Inlet to Cape May NJ out 20 nm-
Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm-
Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm-
1100 AM EDT Sat Jun 20 2020

This Hazardous Weather Outlook is for Atlantic coastal waters and
Delaware Bay Waters.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

NJZ013-020-022-023-027-211500-
Western Monmouth-Ocean-Atlantic-Cape May-Southeastern Burlington-
1100 AM EDT Sat Jun 20 2020

This Hazardous Weather Outlook is for central New Jersey and
southern New Jersey.

.DAY ONE...Today and tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

There is a chance of storms daily through at least Wednesday. Some
of the storms may produce locally heavy rainfall, which may lead to
an isolated instance of flash flooding.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 8:55 PM EDTSpecial Weather StatementPHISussex35 min
Jun 20, 2:57 PM EDTSpecial Weather StatementPHIGloucester33 min
Jun 20, 3:20 PM EDTAreal Flood AdvisoryPHICamden, Gloucester4 hr
Jun 20, 3:29 PM EDTSpecial Weather StatementPHICamden, Gloucester31 min
Jun 20, 3:34 PM EDTFlash Flood WarningPHICamden, Gloucester4 hr
Jun 20, 3:43 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden32 min
Jun 20, 4:08 PM EDTSpecial Weather StatementPHIBurlington37 min
Jun 20, 5:00 PM EDTSpecial Weather StatementPHIHunterdon30 min
Jun 20, 5:27 PM EDTSpecial Weather StatementPHIHunterdon33 min
Jun 20, 5:30 PM EDTSpecial Weather StatementPHIUnion15 min
Jun 20, 5:53 PM EDTAreal Flood AdvisoryPHIHunterdon3 hr
Jun 20, 5:53 PM EDTSpecial Weather StatementPHIMorris, Sussex52 min
Jun 20, 2:19 PM EDTAreal Flood AdvisoryPHIChester2 hr
Jun 20, 4:09 PM EDTAreal Flood AdvisoryPHIBerks3 hr
Jun 20, 4:10 PM EDTSpecial Weather StatementPHIPhiladelphia35 min

Nearby

Areal Flood Advisories in Delaware, 2020Areal Flood Advisories in New Jersey, 2020Every areal flood advisory in 2020

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.