Alert archive / Pennsylvania / Areal Flood Warnings in 2025

Areal Flood Warning 11, NWS Philadelphia/Mount Holly

May 16, 2025Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this areal flood warning at May 16, 2025, 3:53 PM EDT for Montgomery County, Pennsylvania. It was in force for 100 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 16, 2025, 3:53 PM EDT (19:53 UTC)
Expired: May 16, 2025, 5:33 PM EDT
In force: 100 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon
Flood severity: None

County Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 86 km from the middle of the area, began a volume at 19:56 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, 7.9 hours before the alert went out and 224 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: 657 J/kg
Mixed-layer CIN: -104 J/kg
Mixed-layer LCL: 781 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 33 m²/s²
0-3 km storm-relative helicity: 31 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.9

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 16, 2:36 PM EDT, 1 hour 17 minutes earlier.

Area forecast discussion, May 16, 2:36 PM EDT, 1 hour 17 minutes before

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In the hours before

Local storm report, May 16, 2:10 PM EDT, 1 hour 43 minutes before

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
210 PM EDT Fri May 16 2025

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

0145 PM     Tstm Wnd Dmg     2 S Dennisville         39.17N 74.81W
05/16/2025                   Cape May           NJ   Fire Dept/Rescue

            Wires down on Gravel Hole Road and Holly
            Glen Lane. Wires sparking. Time estimated
            from radar.

&&

Hoeflich

Local storm report, May 16, 2:12 PM EDT, 1 hour 41 minutes before

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
212 PM EDT Fri May 16 2025

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

1241 PM     Tstm Wnd Dmg     Monroe Twp              39.69N 75.03W
05/16/2025                   Gloucester         NJ   911 Call Center

            Trees and wires down throughout the area.
            Time estimated from radar.

&&

ZC

Local storm report, May 16, 2:14 PM EDT, 1 hour 39 minutes before

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
214 PM EDT Fri May 16 2025

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

1238 PM     Tstm Wnd Dmg     Washington Twp          39.76N 75.10W
05/16/2025                   Gloucester         NJ   911 Call Center

            Trees and powerlines down. Time estimated
            from radar.

&&

ZC

Local storm report, May 16, 2:15 PM EDT, 1 hour 38 minutes before

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
215 PM EDT Fri May 16 2025

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

0200 PM     Hail             Avalon                  39.10N 74.72W
05/16/2025  E1.75 Inch       Cape May           NJ   Amateur Radio

            Hail up to the size of golf ball. Time
            estimated from radar.

&&

NG

Local storm report, May 16, 2:41 PM EDT, 1 hour 12 minutes before

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
241 PM EDT Fri May 16 2025

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

0231 PM     Hail             1 SE Millsboro          38.58N 75.30W
05/16/2025  M1.75 Inch       Sussex             DE   Public

            Report from mPING: Golf Ball (1.75 in.).

&&

Hoeflich

Local storm report, May 16, 2:53 PM EDT, 1 hour before

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
253 PM EDT Fri May 16 2025

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

0245 PM     Flash Flood      1 NNE Marshallton       39.97N 75.67W
05/16/2025                   Chester            PA   Other Federal

            Downington (DWNP1) 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 15, 9:30 PM EDT	Marine Dense Fog Advisory	PHI		15 hr
May 15, 9:34 PM EDT	Dense Fog Advisory	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more	12 hr
May 16, 11:16 AM EDT	Severe Thunderstorm Warning	PHI	Camden, Gloucester	59 min
May 16, 11:32 AM EDT	Flash Flood Warning	PHI	Burlington, Camden, Gloucester, Mercer, Salem	4 hr
May 16, 11:41 AM EDT	Special Marine Warning	PHI		49 min
May 16, 11:46 AM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Gloucester, Salem	59 min
May 16, 12:20 PM EDT	Severe Thunderstorm Warning	PHI	Camden, Cumberland, Gloucester, Salem	40 min
May 16, 12:22 PM EDT	Tornado Warning	PHI	Cumberland, Salem	23 min
May 16, 12:31 PM EDT	Flash Flood Warning Considerable damage threat	PHI	Camden, Gloucester	4 hr
May 16, 12:42 PM EDT	Tornado Warning	PHI	Atlantic, Cape May, Cumberland	48 min
May 16, 12:45 PM EDT	Tornado Warning	PHI	Atlantic, Camden, Gloucester	30 min
May 16, 12:47 PM EDT	Flash Flood Warning Considerable damage threat	PHI	Burlington, Camden, Gloucester, Salem	4 hr
May 16, 12:49 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 1 more	56 min
May 16, 12:51 PM EDT	Special Marine Warning	PHI		114 min
May 16, 12:52 PM EDT	Tornado Warning	PHI	Atlantic, Camden, Gloucester	23 min
May 16, 1:26 PM EDT	Severe Thunderstorm Warning	PHI	Cape May, Cumberland	49 min
May 16, 1:28 PM EDT	Flash Flood Warning	PHI	Burlington, Ocean	3 hr
May 16, 1:32 PM EDT	Special Marine Warning	PHI		88 min
May 16, 1:36 PM EDT	Flash Flood Warning Considerable damage threat	PHI	Atlantic, Cape May, Ocean	3 hr
May 16, 1:58 PM EDT	Severe Thunderstorm Warning	PHI	Cape May	32 min
May 16, 2:01 PM EDT	Special Marine Warning	PHI		86 min
May 16, 2:24 PM EDT	Areal Flood Warning	PHI	Hunterdon, Somerset	94 min
May 16, 6:31 PM EDT	Special Marine Warning	PHI		119 min
May 16, 6:35 PM EDT	Severe Thunderstorm Warning Considerable damage threat	PHI	Cape May, Cumberland, Gloucester, Salem	70 min
May 16, 10:24 AM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Carbon, Chester, Lehigh, Monroe and 2 more	66 min
May 16, 11:22 AM EDT	Severe Thunderstorm Warning	PHI	Bucks, Chester, Montgomery, Philadelphia	53 min
May 16, 11:41 AM EDT	Flash Flood Warning	PHI	Chester, Delaware	4 hr
May 16, 12:21 PM EDT	Flash Flood Warning	PHI	Bucks, Montgomery	4 hr
May 16, 2:02 PM EDT	River Flood Warning	PHI	Chester	5 hr
May 16, 3:29 PM EDT	Areal Flood Warning	PHI	Berks	6 hr
May 16, 4:42 PM EDT	Areal Flood Warning	PHI	Montgomery, Philadelphia	4 hr
May 16, 5:15 PM EDT	Areal Flood Warning	PHI	Bucks	112 min
May 16, 6:43 PM EDT	Areal Flood Warning	PHI	Philadelphia	113 min
May 16, 1:52 PM EDT	Tornado Warning	PHI	Sussex	38 min
May 16, 2:18 PM EDT	Severe Thunderstorm Warning	PHI	Sussex	42 min
May 16, 2:23 PM EDT	Tornado Warning	PHI	Sussex	52 min
May 16, 6:56 PM EDT	Tornado Warning	PHI	Sussex	34 min

Nearby

Areal Flood Warnings in Pennsylvania, 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.