Alert archive / Pennsylvania / Areal Flood Advisories in 2018
Areal Flood Advisory 296, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this areal flood advisory at Sep 18, 2018, 2:38 AM EDT for Chester County, Montgomery County, Pennsylvania. It was in force for 4 hr.
The area
The counties it named.
The facts
- Issued
- Sep 18, 2018, 2:38 AM EDT (06:38 UTC)
- Expired
- Sep 18, 2018, 6:45 AM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
Counties Chester County, PA, Montgomery County, PA
The radar
The Philadelphia radar (KDIX), 99 km from the middle of the area, began a volume at 06:40 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 00:00Z, 6.6 hours before the alert went out and 203 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
- 709 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 587 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 178 m²/s²
- 0-3 km storm-relative helicity
- 256 m²/s²
- Significant tornado parameter
- 0.5
- Supercell composite
- 4.8
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 Sep 18, 12:50 AM EDT, 1 hour 48 minutes earlier.
Area forecast discussion, Sep 18, 12:50 AM EDT, 1 hour 48 minutes before
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</html>Hazardous weather outlook, Sep 17, 3:34 PM EDT, 11 hours 4 minutes before
Hazardous Weather Outlook National Weather Service Mount Holly NJ 334 PM EDT Mon Sep 17 2018 DEZ001>003-MDZ008-012-015-019-020-NJZ001-007>010-012-013-015>023-027- PAZ054-055-060>062-070-071-101>106-181945- New Castle-Kent-Inland Sussex-Cecil-Kent MD-Queen Annes-Talbot- Caroline-Sussex-Warren-Morris-Hunterdon-Somerset-Middlesex- Western Monmouth-Mercer-Salem-Gloucester-Camden- Northwestern Burlington-Ocean-Cumberland-Atlantic-Cape May- Southeastern Burlington-Carbon-Monroe-Berks-Lehigh-Northampton- Delaware-Philadelphia-Western Chester-Eastern Chester- Western Montgomery-Eastern Montgomery-Upper Bucks-Lower Bucks- 334 PM EDT Mon Sep 17 2018 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...This Afternoon and Tonight. Periods of heavy rain and showers through tonight from the remnants of Florence may result in localized flash flooding. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. Some heavy rain Tuesday from the remnants of Florence and a cold front may result in localized flash flooding. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. DEZ004-NJZ014-024>026-181945- Delaware Beaches-Eastern Monmouth-Atlantic Coastal Cape May- Coastal Atlantic-Coastal Ocean- 334 PM EDT Mon Sep 17 2018 This Hazardous Weather Outlook is for southern Delaware, central New Jersey and southern New Jersey. .DAY ONE...This Afternoon and Tonight. There is a moderate risk of dangerous rip currents. Periods of heavy rain and showers through tonight from the remnants of Florence may result in localized flash flooding. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. Some heavy rain Tuesday from the remnants of Florence and a cold front may result in localized flash flooding. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to standard operating procedures. ANZ430-431-450>455-181945- 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- 334 PM EDT Mon Sep 17 2018 This Hazardous Weather Outlook is for Atlantic coastal waters and Delaware Bay Waters. .DAY ONE...This Afternoon and Tonight. The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. 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.
In the hours before
Special weather statement, Sep 18, 1:13 AM EDT, 1 hour 25 minutes before
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</html>Special weather statement, Sep 18, 2:09 AM EDT, 29 minutes before
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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 |
|---|---|---|---|---|
| Sep 18, 4:13 AM EDT | Special Weather Statement | PHI | Camden, Gloucester, Salem | 92 min |
| Sep 18, 9:27 AM EDT | Flash Flood Watch | PHI | Burlington, Camden, Gloucester, Hunterdon, Mercer, Middlesex and 5 more | 6 hr |
| Sep 18, 10:59 AM EDT | Areal Flood Advisory | PHI | Hunterdon, Mercer, Middlesex, Monmouth, Somerset | 4 hr |
| Sep 18, 12:01 PM EDT | Flash Flood Warning | PHI | Mercer, Middlesex, Somerset | 4 hr |
| Sep 18, 12:16 PM EDT | Special Weather Statement | PHI | Middlesex | 29 min |
| Sep 18, 12:36 PM EDT | Areal Flood Advisory | PHI | Burlington, Camden, Gloucester, Mercer, Middlesex, Monmouth and 2 more | 3 hr |
| Sep 18, 1:20 PM EDT | Special Weather Statement | PHI | Burlington | 25 min |
| Sep 18, 1:35 PM EDT | Special Marine Warning | PHI | 55 min | |
| Sep 18, 2:51 PM EDT | Special Marine Warning | PHI | 38 min | |
| Sep 18, 2:55 PM EDT | Special Weather Statement | PHI | Ocean | 35 min |
| Sep 18, 3:02 PM EDT | Areal Flood Advisory | PHI | Burlington, Ocean | 3 hr |
| Sep 18, 3:12 PM EDT | Areal Flood Advisory | PHI | Atlantic, Burlington, Camden, Ocean | 47 min |
| Sep 18, 3:47 PM EDT | Special Weather Statement | PHI | Ocean | 28 min |
| Sep 18, 4:12 PM EDT | Special Weather Statement | PHI | Atlantic | 33 min |
| Sep 18, 4:47 PM EDT | Areal Flood Advisory | PHI | Atlantic, Cape May, Cumberland, Ocean | 2 hr |
| Sep 18, 5:17 PM EDT | Flash Flood Warning | PHI | Atlantic | 113 min |
| Sep 18, 1:13 AM EDT | Special Weather Statement | PHI | Chester | 62 min |
| Sep 18, 2:09 AM EDT | Special Weather Statement | PHI | Chester, Delaware, Montgomery, Philadelphia | 81 min |
| Sep 18, 6:27 AM EDT | Areal Flood Advisory | PHI | Carbon, Monroe | 4 hr |
| Sep 18, 10:57 AM EDT | Areal Flood Advisory | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 3 hr |
| Sep 18, 5:26 PM EDT | Special Weather Statement | PHI | Sussex | 34 min |
Nearby
Areal Flood Advisories in Pennsylvania, 2018Every areal flood advisory 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.