Alert archive / New Jersey / Areal Flood Warnings in 2025

Areal Flood Warning 20, NWS Philadelphia/Mount Holly

May 31, 2025Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this areal flood warning at May 31, 2025, 5:13 AM EDT for Somerset County, New Jersey. It was in force for 97 min. 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 31, 2025, 5:13 AM EDT (09:13 UTC)
Expired: May 31, 2025, 6:50 AM EDT
In force: 97 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

County Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 71 km from the middle of the area, began a volume at 09:15 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

Albany, NY (KALY), launched 00:00Z, 9.2 hours before the alert went out and 245 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: 37 J/kg
Mixed-layer CIN: -29 J/kg
Mixed-layer LCL: 1565 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 27 m²/s²
0-3 km storm-relative helicity: 89 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 31, 3:43 AM EDT, 1 hour 30 minutes earlier.

Area forecast discussion, May 31, 3:43 AM EDT, 1 hour 30 minutes before

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In the hours before

Local storm report, May 31, 12:20 AM EDT, 4 hours 53 minutes before

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Local storm report, May 31, 12:30 AM EDT, 4 hours 43 minutes before

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Local storm report, May 31, 1:26 AM EDT, 3 hours 47 minutes before

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Local storm report, May 31, 1:30 AM EDT, 3 hours 43 minutes before

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Local storm report, May 31, 2:50 AM EDT, 2 hours 23 minutes before

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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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Local storm report, May 31, 4:44 AM EDT, 29 minutes before

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
444 AM EDT Sat May 31 2025

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

0430 AM     Flood            3 NE Ringoes            40.47N 74.83W
05/31/2025                   Hunterdon          NJ   Other Federal

            The Neshanic River at Reaville (REAN4) went
            into flood stage.

&&

Hoeflich

The office that day

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

Issued	Product	Office	Counties	Lasted
May 30, 9:04 PM EDT	Wind Advisory	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more	10 hr
May 30, 11:12 PM EDT	Flash Flood Warning	PHI	Gloucester, Salem	3 hr
May 30, 11:36 PM EDT	Flash Flood Warning	PHI	Burlington, Camden, Gloucester	4 hr
May 31, 12:34 AM EDT	Flash Flood Warning	PHI	Burlington, Mercer	3 hr
May 31, 4:00 AM EDT	Areal Flood Warning	PHI	Morris, Sussex, Warren	9 hr
May 31, 4:19 AM EDT	Areal Flood Warning	PHI	Hunterdon	6 hr
May 31, 8:46 AM EDT	Areal Flood Warning	PHI	Somerset	7 hr
May 31, 2:12 PM EDT	Special Marine Warning	PHI		63 min
May 31, 3:10 PM EDT	Special Marine Warning	PHI		65 min
May 31, 3:14 PM EDT	Severe Thunderstorm Warning	PHI	Cape May	16 min
May 31, 4:51 PM EDT	Special Marine Warning	PHI		84 min
May 31, 5:04 PM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Gloucester, Salem	41 min
May 31, 6:20 PM EDT	River Flood Warning	PHI	Morris	12 hr
May 31, 1:04 AM EDT	Flash Flood Warning	PHI	Berks, Bucks, Lehigh, Montgomery	4 hr
May 31, 5:06 AM EDT	Areal Flood Warning	PHI	Lehigh, Montgomery	5 hr
May 31, 8:42 AM EDT	Areal Flood Warning	PHI	Lehigh	4 hr
May 30, 10:26 PM EDT	Flash Flood Warning	PHI	New Castle	4 hr
May 30, 10:26 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	49 min
May 30, 10:55 PM EDT	Tornado Warning	PHI	New Castle	22 min
May 31, 1:17 PM EDT	Severe Thunderstorm Warning	PHI	Kent	43 min
May 31, 1:30 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	45 min
May 31, 1:42 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	48 min
May 31, 2:00 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Sussex	45 min
May 31, 2:26 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	49 min

Nearby

Areal Flood Warnings in New Jersey, 2025 Every areal flood warning in 2025

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.