Alert archive / Pennsylvania / Areal Flood Advisories in 2020
Areal Flood Advisory 33, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this areal flood advisory at Jun 19, 2020, 3:46 PM EDT for Chester County, Pennsylvania; New Castle County, Delaware. It was in force for 4 hr.
The area
The counties it named.
The facts
- Issued
- Jun 19, 2020, 3:46 PM EDT (19:46 UTC)
- Expired
- Jun 19, 2020, 7:45 PM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties New Castle County, DE, Chester County, PA
The radar
The Dover AFB radar (KDOX), 108 km from the middle of the area, began a volume at 19:47 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, 7.8 hours before the alert went out and 173 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.
- Mixed-layer CAPE
- 568 J/kg
- Mixed-layer CIN
- -34 J/kg
- Mixed-layer LCL
- 631 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 64 m²/s²
- 0-3 km storm-relative helicity
- 61 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.6
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 19, 2:06 PM EDT, 1 hour 40 minutes earlier.
Area forecast discussion, Jun 19, 2:06 PM EDT, 1 hour 40 minutes before
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</html>Hazardous weather outlook, Jun 19, 11:11 AM EDT, 4 hours 35 minutes before
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The site you requested is temporarily down for maintenance or an unexpected outage.
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</html>The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 18, 8:27 PM EDT | Dense Fog Advisory | PHI | Atlantic, Cape May, Monmouth, Ocean | 12 hr |
| Jun 19, 7:40 PM EDT | Special Weather Statement | PHI | Somerset | 35 min |
| Jun 19, 7:56 PM EDT | Areal Flood Advisory | PHI | Hunterdon, Mercer, Middlesex, Morris, Somerset | 3 hr |
| Jun 19, 2:40 PM EDT | Areal Flood Advisory | PHI | Berks | 4 hr |
| Jun 19, 4:34 PM EDT | Areal Flood Advisory | PHI | Chester | 3 hr |
| Jun 19, 5:21 PM EDT | Areal Flood Advisory | PHI | Berks, Chester, Montgomery | 2 hr |
| Jun 19, 5:49 PM EDT | Special Weather Statement | PHI | Lehigh | 26 min |
| Jun 19, 6:46 PM EDT | Areal Flood Advisory | PHI | Carbon, Lehigh, Monroe, Northampton | 3 hr |
Nearby
Areal Flood Advisories in Pennsylvania, 2020Areal Flood Advisories in Delaware, 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.