Alert archive / Delaware / Areal Flood Advisories in 2019

Areal Flood Advisory 53, NWS Philadelphia/Mount Holly

May 20, 2019Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this areal flood advisory at May 20, 2019, 6:50 PM EDT for Sussex County, Delaware. It was in force for 3 hr.

The area

The counties it named.

The facts

Issued: May 20, 2019, 6:50 PM EDT (22:50 UTC)
Expired: May 20, 2019, 9:45 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), 18 km from the middle of the area, began a volume at 22:50 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.8 hours before the alert went out and 181 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: 15 J/kg
Mixed-layer CIN: -173 J/kg
Mixed-layer LCL: 1480 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 70 m²/s²
0-3 km storm-relative helicity: 58 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 May 20, 6:26 PM EDT, 24 minutes earlier.

Area forecast discussion, May 20, 6:26 PM EDT, 24 minutes before

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Hazardous weather outlook, May 20, 3:43 PM EDT, 3 hours 7 minutes before

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        The site you requested is temporarily down for maintenance or an unexpected outage.
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The office that day

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

Issued	Product	Office	Counties	Lasted
May 19, 9:46 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Morris, Somerset, Warren	44 min
May 19, 10:27 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Mercer, Middlesex, Monmouth, Morris, Ocean and 1 more	48 min
May 19, 10:34 PM EDT	Areal Flood Advisory	PHI	Hunterdon, Mercer, Middlesex, Morris, Somerset, Sussex and 1 more	3 hr
May 19, 11:41 PM EDT	Severe Thunderstorm Warning	PHI	Warren	53 min
May 20, 1:03 AM EDT	Special Weather Statement	PHI	Morris, Warren	57 min
May 19, 8:14 PM EDT	Special Weather Statement	PHI	Lehigh	46 min
May 19, 8:35 PM EDT	Tornado Warning	PHI	Berks	25 min
May 19, 8:37 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh, Montgomery	38 min
May 19, 8:43 PM EDT	Flash Flood Warning	PHI	Berks	3 hr
May 19, 9:09 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Chester, Lehigh, Montgomery, Northampton	51 min
May 19, 9:29 PM EDT	Flash Flood Warning	PHI	Berks, Bucks, Lehigh, Montgomery, Northampton	4 hr
May 19, 10:48 PM EDT	Flash Flood Warning	PHI	Berks	117 min
May 19, 11:00 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Carbon, Lehigh, Monroe, Northampton	60 min
May 19, 11:15 PM EDT	Flash Flood Warning	PHI	Carbon, Lehigh, Monroe, Northampton	3 hr
May 19, 11:54 PM EDT	Severe Thunderstorm Warning	PHI	Lehigh, Northampton	39 min
May 20, 12:57 AM EDT	Areal Flood Advisory	PHI	Berks	3 hr
May 20, 1:21 AM EDT	Areal Flood Advisory	PHI	Berks, Montgomery	3 hr
May 20, 5:57 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	20 min

Nearby

Areal Flood Advisories in Delaware, 2019 Every areal flood advisory in 2019

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.