Alert archive / Pennsylvania / Areal Flood Warnings in 2024

Areal Flood Warning 81, NWS Philadelphia/Mount Holly

April 4, 2024Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood warning at Apr 4, 2024, 4:13 AM EDT for Lehigh County, Pennsylvania. It was in force for 7 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
Apr 4, 2024, 4:13 AM EDT (08:13 UTC)
Expired
Apr 4, 2024, 11:23 AM EDT
In force
7 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 125 km from the middle of the area, began a volume at 08:15 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, 8.2 hours before the alert went out and 231 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 2024-04-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2024-04-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 613 square meters per square second.1939587897117136156Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
634 m above ground
0-6 km bulk shear
62 kt
0-1 km storm-relative helicity
613 m²/s²
0-3 km storm-relative helicity
1325 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 Apr 4, 4:05 AM EDT, 8 minutes earlier.

Area forecast discussion, Apr 4, 4:05 AM EDT, 8 minutes before
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Hazardous weather outlook, Apr 4, 3:57 AM EDT, 16 minutes before
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In the hours before

Local storm report, Apr 3, 10:44 PM EDT, 5 hours 29 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
1044 PM EDT Wed Apr 3 2024

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

1016 PM     Marine Tstm Wind Indian Beach            38.68N 75.08W
04/03/2024  M43 MPH          Sussex             DE   Mesonet

            Dewey Beach WeatherFlow mesonet station
            reported 37 kt (43 mph) gust.

&&

MJL
Local storm report, Apr 3, 10:47 PM EDT, 5 hours 26 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
1047 PM EDT Wed Apr 3 2024

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

1035 PM     Marine Tstm Wind 1 SSW North Cape May    38.97N 74.96W
04/03/2024  M41 MPH          Cape May           NJ   Mesonet

            Cape May WeatherFlow mesonet station
            reported a 36 kt (41 mph) wind gust.

&&

MJL

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 3, 8:04 PM EDTSmall Craft AdvisoryPHI42 hr
Apr 3, 10:11 PM EDTSpecial Marine WarningPHI34 min
Apr 3, 10:16 PM EDTSpecial Marine WarningPHI44 min
Apr 3, 10:46 PM EDTSpecial Marine WarningPHI59 min
Apr 3, 11:20 PM EDTSpecial Marine WarningPHI55 min
Apr 3, 11:23 PM EDTSpecial Marine WarningPHI52 min
Apr 4, 12:06 AM EDTSpecial Marine WarningPHI39 min
Apr 4, 12:16 AM EDTSpecial Marine WarningPHI59 min
Apr 4, 12:45 AM EDTSpecial Marine WarningPHI7 min
Apr 4, 1:32 AM EDTRiver Flood WarningPHIMiddlesex, Somerset12 hr
Apr 4, 1:37 AM EDTAreal Flood WarningPHICumberland, Salem70 hr
Apr 4, 2:20 AM EDTAreal Flood WarningPHIWarren26 hr
Apr 4, 4:40 AM EDTRiver Flood WarningPHIPassaic11 hr
Apr 4, 7:42 AM EDTRiver Flood WarningPHIEssex, Passaic3 days
Apr 4, 7:43 AM EDTRiver Flood WarningPHIEssex, Morris, Passaic4 days
Apr 4, 10:07 AM EDTCoastal Flood WarningPHIOcean4 hr
Apr 4, 10:07 AM EDTCoastal Flood AdvisoryPHIOcean16 hr
Apr 4, 6:35 PM EDTSpecial Marine WarningPHI55 min
Apr 4, 6:43 PM EDTSpecial Marine WarningPHI62 min
Apr 3, 8:39 PM EDTAreal Flood WarningPHILehigh, Northampton4 hr
Apr 4, 3:25 AM EDTAreal Flood WarningPHIMontgomery6 hr
Apr 4, 6:50 PM EDTSpecial Weather StatementPHIChester25 min

Nearby

Areal Flood Warnings in Pennsylvania, 2024Every areal flood warning in 2024

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.