Alert archive / Pennsylvania / Areal Flood Warnings in 2023

Areal Flood Warning 15, NWS Philadelphia/Mount Holly

May 1, 2023Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood warning at May 1, 2023, 5:22 AM EDT for Philadelphia County, Pennsylvania. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 1, 2023, 5:22 AM EDT (09:22 UTC)
Expired
May 1, 2023, 11:19 AM EDT
In force
6 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 62 km from the middle of the area, began a volume at 09:23 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

Brookhaven, NY (KOKX), launched 00:00Z, 9.4 hours before the alert went out and 214 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, Brookhaven, NY at 00:00Z on 2023-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 187 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, Brookhaven, NY at 00:00Z on 2023-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 84 square meters per square second.1939587897Sfc1 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
187 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
467 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
84 m²/s²
0-3 km storm-relative helicity
19 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 warning 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 warning went out at May 1, 4:52 AM EDT, 30 minutes earlier.

Area forecast discussion, May 1, 4:52 AM EDT, 30 minutes before
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Hazardous weather outlook, May 1, 5:05 AM EDT, 17 minutes before
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In the hours before

Local storm report, May 1, 1:52 AM EDT, 3 hours 30 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
152 AM EDT MON MAY 1 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1245 AM     NON-TSTM WND GST 4 SE MYSTIC ISLAND      39.52N 74.32W
05/01/2023  M44 MPH          OCEAN              NJ   MESONET

            LITTLE EGG HARBOR TOWNSHIP MESONET STATION.

&&

MLB
Local storm report, May 1, 1:54 AM EDT, 3 hours 28 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
154 AM EDT MON MAY 1 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1230 AM     NON-TSTM WND GST FORTESCUE               39.24N 75.18W
05/01/2023  M43 MPH          CUMBERLAND         NJ   MESONET

            CORRECTS DATE OF PREVIOUS NON-TSTM WND GST
            REPORT FROM FORTESCUE. MESONET STATION NJ67
            FORTESQUE.

&&

MLB
Local storm report, May 1, 1:59 AM EDT, 3 hours 23 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
159 AM EDT MON MAY 1 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0145 AM     NON-TSTM WND GST HARVEY CEDARS           39.70N 74.14W
05/01/2023  M44 MPH          OCEAN              NJ   MESONET

            MESONET STATION NJ11 HARVEY CEDARS.

&&

MLB
Local storm report, May 1, 4:39 AM EDT, 43 minutes before
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Local storm report, May 1, 4:43 AM EDT, 39 minutes before
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Local storm report, May 1, 4:44 AM EDT, 38 minutes before
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      <h1 id="headline">This service is currently unavailable.</h1>
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The office that day

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

IssuedProductOfficeCountiesLasted
Apr 30, 8:34 PM EDTAreal Flood AdvisoryPHIBurlington, Camden, Gloucester, Mercer, Middlesex, Monmouth100 min
Apr 30, 8:55 PM EDTAreal Flood AdvisoryPHIBurlington, Camden, Gloucester3 hr
Apr 30, 10:14 PM EDTAreal Flood WarningPHIBurlington, Camden, Gloucester, Mercer, Middlesex3 hr
Apr 30, 10:31 PM EDTRiver Flood WarningPHIMorris, Somerset24 hr
Apr 30, 10:34 PM EDTRiver Flood WarningPHIBurlington13 hr
Apr 30, 10:37 PM EDTRiver Flood WarningPHIEssex, Morris, Passaic6 days
Apr 30, 10:49 PM EDTAreal Flood AdvisoryPHIHunterdon, Warren50 min
Apr 30, 11:03 PM EDTAreal Flood AdvisoryPHIMiddlesex, Morris, Somerset117 min
Apr 30, 11:11 PM EDTRiver Flood WarningPHIMorris, Passaic32 hr
Apr 30, 11:39 PM EDTAreal Flood WarningPHIHunterdon, Warren5 hr
May 1, 12:15 AM EDTSpecial Marine WarningPHI90 min
May 1, 12:17 AM EDTSpecial Marine WarningPHI88 min
May 1, 12:28 AM EDTRiver Flood WarningPHIMorris48 hr
May 1, 12:47 AM EDTAreal Flood WarningPHIHunterdon, Mercer, Middlesex, Morris, Somerset, Sussex and 1 more10 hr
May 1, 1:40 AM EDTSpecial Marine WarningPHI65 min
May 1, 1:41 AM EDTSpecial Marine WarningPHI64 min
May 1, 2:33 AM EDTAreal Flood WarningPHIBurlington7 hr
May 1, 3:47 AM EDTRiver Flood WarningPHIEssex, Morris, Passaic4 days
May 1, 3:50 AM EDTRiver Flood WarningPHISomerset27 hr
May 1, 7:46 AM EDTAreal Flood WarningPHIMonmouth, Ocean9 hr
May 1, 8:00 AM EDTAreal Flood WarningPHICumberland, Gloucester, Salem60 hr
May 1, 10:48 AM EDTAreal Flood WarningPHISomerset6 hr
May 1, 12:18 PM EDTRiver Flood WarningPHIEssex, Passaic65 hr
May 1, 12:33 PM EDTAreal Flood WarningPHIAtlantic, Camden, Gloucester54 hr
May 1, 4:38 PM EDTSpecial Weather StatementPHIWarren37 min
May 1, 5:16 PM EDTSpecial Weather StatementPHIMorris, Sussex, Warren44 min
Apr 30, 8:14 PM EDTAreal Flood AdvisoryPHIBerks, Chester3 hr
May 1, 2:17 AM EDTAreal Flood WarningPHIMontgomery3 hr
May 1, 2:20 AM EDTAreal Flood WarningPHIChester3 hr
May 1, 2:44 AM EDTAreal Flood WarningPHIMontgomery2 hr
May 1, 3:24 AM EDTAreal Flood WarningPHIBucks5 hr
May 1, 5:36 AM EDTRiver Flood WarningPHIBucks7 hr

Nearby

Areal Flood Warnings in Pennsylvania, 2023Every areal flood warning in 2023

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.