Pennsylvania, 2026

Flash Flooding in Pennsylvania, June 22, 2026

June 22, 2026 · NWS PHI · 3 events in 2 counties and zones

An approaching warm front produced showers and thunderstorms over portions of the Delaware Valley up through northern New Jersey. A few of these storms produced heavy rain.

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
$85,000
Crop damage
None recorded
Events
3

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS PHI wrote it up.

An approaching warm front produced showers and thunderstorms over portions of the Delaware Valley up through northern New Jersey. A few of these storms produced heavy rain.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Jun 22, 3:46 PM EST, 1 hour 37 minutes earlier. Its key messages:

  • 1. Low pressure will bring showers and thunderstorms this afternoon into this evening bringing both the threat of severe weather and flash flooding. Additional rounds of showers and storms now are likely for Tuesday. 2. A HIGH risk of rip currents today for coastal Ocean, Atlantic, and Cape May county. 3. Another cold front is expected to approach the region late this week, bringing more chances for showers and storms.
Area forecast discussion, Jun 22, 3:46 PM EST, 1 hour 37 minutes before
Area Forecast Discussion
National Weather Service Mount Holly NJ
446 PM EDT Mon Jun 22 2026

.WHAT HAS CHANGED...
1. A Severe Thunderstorm Watch has been issued for the majority
of our area and is in effect until 9 PM.

2. Showers/storms now look to linger into Tuesday as the frontal
system now looks slower to depart.

3. Updated Aviation section for 18z TAFs.

&&

.KEY MESSAGES...
1. Low pressure will bring showers and thunderstorms this
afternoon into this evening bringing both the threat of severe
weather and flash flooding. Additional rounds of showers and
storms now are likely for Tuesday.

2. A HIGH risk of rip currents today for coastal Ocean,
Atlantic, and Cape May county.

3. Another cold front is expected to approach the region late
this week, bringing more chances for showers and storms.

&&

.DISCUSSION...
KEY MESSAGE 1...Low pressure will bring showers and thunderstorms this
afternoon into this evening bringing both the threat of severe
weather and flash flooding. Additional rounds of showers and
storms now are likely for Tuesday.

Low pressure will be moving across southern PA then through NJ
en-route to Long Island as we go through the rest of the day
through tonight. As of mid afternoon, we're already seeing some
showers storms developing near and north of the system's warm
front as it's situated over SE PA into NJ. ML CAPE values are in
the neighborhood of 1000-1500+ j/kg and in addition to this
there is both strong low level and deep layer shear...especially
near and north of the front. PWAT values are increasing as well
and already around 1.8+ inches. The upshot of this is that
expect showers/storms to continue to developing and become
more widespread through late this afternoon into this evening.
This will occur as the low continues to approach with a surface
trough ahead of it extending from eastern PA southward towards
the Chesapeake. Expect the main area of storms to move through
roughly in the 5-9 PM time frame. Damaging winds and flash
flooding from heavy rainfall are the biggest threats but
isolated tornadoes will also be possible. And it appears that
specifically regarding the TOR threat, it will be greatest near
the warm front meaning the I-76 / I-276 / I-195 corridor north
towards the I-78 corridor over eastern PA into NJ. South of here
damaging winds look to be the biggest threat in terms of severe
weather. As for the heavy rainfall and flash flooding threat,
the highest chances for this will be near the urban corridor.
Individual cell motion is fast but there is the potential for
some training and backbuilding to develop by early this evening
and if this sets up in urban areas, it will result in flash
flooding.

Getting towards the mid evening period, the severe weather
threat should be diminishing but the low looks to be very slow
moving across the area through the overnight meaning more
showers and possible storms will be likely. It's for this reason
that we have the Flood Watch going through the night to 6 AM
Tuesday.

For Tuesday, the big change in the forecast is that the system
now looks to get hung up over the area with the latest
indications actually being for a new low to develop near near
Delmarva. This will occur as another piece of energy moves
around the base of the upper trough over the east. This will
result in more rounds of showers and storms that could once
again be on the heavier side by the afternoon. Near the warm
sector over southern Delmarva, we can't rule out some storms
becoming severe and the SPC now has a MARGINAL risk for severe
storms just getting into Sussex County Delaware.

Low pressure with it's associated showers/storms should finally
move out through Tuesday night.

KEY MESSAGE 2...A HIGH risk of rip currents today for coastal
Ocean, Atlantic, and Cape May county.

For today, south-southeasterly winds will increase to around
15-20 mph with gusts upwards of 25-30 mph. South-southeasterly
onshore swells will increase to around 3 to 4 feet with a 6
second period. Breaking waves in the surf zone will generally be
2 to 4 feet. Due to the increase in a more onshore wind and
wave heights also increasing, a HIGH risk for the development of
dangerous rip currents is forecast for coastal Ocean, Atlantic,
and Cape May county. A Rip Current Statement remains in effect
until 8 PM today for these coastal areas. There is a MODERATE
risk for the development of dangerous rip currents at coastal
Monmouth and the Delaware Beaches. For these coastal zones, the
wind is more shore parallel.

On Tuesday, winds will be out of the south to southwest around
10 mph, turning to the north at 10 to 15 mph with gusts up to 20
mph in the afternoon. Breaking waves will be 1 to 3 feet with a
light southeasterly swell with a period around 6 seconds. As a
result, there is a LOW risk for the development of dangerous and
life threatening rip currents for the Jersey Shore and Delaware
Beaches.

On Wednesday, winds will be light and variable in the morning,
turning south around 10 mph in the afternoon. Breaking waves
will be 1 to 2 feet with a light southeast swell with a period
around 7 seconds. As a result, there is a LOW risk for the
development of dangerous and life threatening rip currents for
the Jersey Shore and Delaware Beaches.

For specific beach forecasts, visit weather.gov/beach/phi

KEY MESSAGE 3...Another cold front is expected to approach the
region late this week, bringing more chances for showers and
storms.

Another cold front is expected to approach our region late in
the week (likely crossing through our region Friday into
Saturday). More showers/storms are likely beginning as early as
late day Thursday and then continuing Friday.  Southwesterly
flow ahead of the front should allow for plenty of moisture
advection ahead of the rain chances. However with the best
forcing more centered north of the region, that could limit how
widespread significant rain is with this event. As for what
hazards to expect with this event, that will be highly dependent
on the timing of the showers and storms, which is still
uncertain.

The front may linger nearby next weekend and if this occurs it
would keep chances for shower/storms going, especially in the
afternoon/evening hours. There is uncertainty regarding this
though.

&&

.AVIATION /20Z MONDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Through tonight...Showers/storms expected to affect the
terminals especially during the 21-01z time frame (except
slightly later for MIV and ACY). These will bring at least
brief periods of IFR visbys with the potential for some brief
wind gusts of 35-40 knots. Thunderstorm activity should be
diminishing by late evening but showers with sub VFR conditions
expect to linger through the night and beyond. It now appears
most site should see IFR cigs by the overnight period. S/SE
winds around 10 knots gusting 20-25 knots this afternoon
shifting to SW this evening and then eventually going to NNW at
5-10 knots by daybreak. Moderate confidence overall.

Tuesday...Sub VFR with more shower and possible storms likely.
The first part of the morning should be mainly IFR due to low
cigs before some improvement will be possible by afternoon.
However any heavier shower/storms by afternoon could bring brief
IFR visbys. Winds northerly around 10 knots.

Outlook...

Wednesday...VFR. No significant weather.

Thursday through Saturday...Chances for shower/storms return
(30 to 50 percent chances) beginning late day Thursday and these
could bring brief restrictions.

&&

.MARINE...
Small Craft Advisory in effect today and tonight with southerly
wind gusts increasing to 30 knots with seas building to 4 to 6
feet. Some gusty thunderstorms will be possible this evening.

After a lull, another period of SCA conditions will be possible
late day Tuesday into Tuesday night due to gusty N/NW winds.

Outlook...

Wednesday through Saturday...Sub SCA conditions.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Flood Watch through late tonight for PAZ070-071-101>106.
NJ...Flood Watch through late tonight for NJZ008>010-012-013-
     015>019.
     High Risk for Rip Currents until 8 PM EDT this evening for
     NJZ024>026.
DE...Flood Watch through late tonight for DEZ001.
MD...None.
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ430-431.
     Small Craft Advisory until 6 AM EDT Tuesday for ANZ450>455.

&&

DISCUSSION...Fitzsimmons/Guzzo/Johnson/RCM
AVIATION...Fitzsimmons/Gorse/Johnson/RCM
MARINE...Fitzsimmons/Guzzo/Johnson/MPS/RCM
Hazardous weather outlook, Jun 22, 4:07 AM EST, 13 hours 16 minutes before
Hazardous Weather Outlook
National Weather Service Mount Holly NJ
507 AM EDT Mon Jun 22 2026

MDZ012-015-019-020-230915-
Kent MD-Queen Annes-Talbot-Caroline-
507 AM EDT Mon Jun 22 2026

This Hazardous Weather Outlook is for northeast Maryland.

.DAY ONE...Today and tonight.

A slight risk of severe thunderstorms and excessive rainfall exists
today and tonight.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Local storm report, Jun 22, 2:33 PM EST, 2 hours 50 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
333 PM EDT Mon Jun 22 2026

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

0248 PM     Hail             1 NE Burlington Twp     40.09N 74.81W
06/22/2026  M1.50 Inch       Burlington         NJ   Public

            2 minutes of hail up to 1.5 inch diameter.
            Time estimated from radar.

&&

Staarmann
Local storm report, Jun 22, 2:38 PM EST, 2 hours 45 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
338 PM EDT Mon Jun 22 2026

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

0243 PM     Tstm Wnd Gst     3 NW Bridgewater        40.62N 74.67W
06/22/2026  M45 MPH          Somerset           NJ   ASOS

            ASOS station KSMQ Somerville.

&&

Staarmann
Local storm report, Jun 22, 4:46 PM EST, 37 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
546 PM EDT Mon Jun 22 2026

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

0452 PM     Hail             1 N Upper Uwchlan Twp   40.10N 75.69W
06/22/2026  M1.00 Inch       Chester            PA   Public

            Report from mPING: Quarter (1.00 in.).

&&

Staarmann
Local storm report, Jun 22, 4:47 PM EST, 36 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
547 PM EDT Mon Jun 22 2026

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

0520 PM     Tstm Wnd Dmg     Marshallton             39.95N 75.68W
06/22/2026                   Chester            PA   Fire Dept/Rescue

            Multiple reports of wires down along Clayton
            Road. Time estimated from radar.

&&

NG
Local storm report, Jun 22, 4:59 PM EST, 24 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
559 PM EDT Mon Jun 22 2026

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

0518 PM     Tstm Wnd Dmg     3 SE West Marlborough T 39.89N 75.77W
06/22/2026                   Chester            PA   Trained Spotter

            Multiple large tree branches snapped near
            the intersection of Newark Road and Clonmell
            Mill Road. A tree is also down on Newark
            road. Time estimated from radar.

&&

NG
Local storm report, Jun 22, 5:11 PM EST, 12 minutes before
Preliminary Local Storm Report
National Weather Service Mount Holly NJ
611 PM EDT Mon Jun 22 2026

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

0605 PM     Flood            1 WSW Shawmont - Philad 40.04N 75.26W
06/22/2026                   Montgomery         PA   Dept of Highways

            Flooding on Schuylkill Expressway/I-76 west
            of Gladwyne. Seen on DOT traffic cameras.

&&

MJL

The radar

The Philadelphia radar (KDIX), 65 km away, was scanning. The volume nearest the first event began at 22:22 UTC.

Open the radar archive at this moment

Event by event

3 flash flood. Local standard time, as filed.

Flash Flood, Montgomery

When
June 22, 5:23 PM EST to 6:23 PM EST
Where
Montgomery County, 1.06 mi E of Hill Crest to 0.53 mi NNW of Ogontz
Cause
Heavy Rain
Property damage
$5,000
Reported by
Fire Department/Rescue
Coordinates
40.080, -75.150

Report of a water rescue near Wyncote.

Flash Flood, Philadelphia

When
June 22, 5:30 PM EST to 7:30 PM EST
Where
Philadelphia County, 1.48 mi NNE of Germantown to 1.35 mi SE of Chestnut Hill
Cause
Heavy Rain
Property damage
$50,000
Reported by
Public
Coordinates
40.050, -75.160

Social and broadcast media showed flooded streets and fast flowing water at least 6 to 12 inches deep in the Germantown area of Philadelphia. Several cars were floating in the water. Basements were flooded.

Flash Flood, Philadelphia

When
June 22, 6:09 PM EST to 8:09 PM EST
Where
Philadelphia County, 1.83 mi SW of West Philadelphia to 1.11 mi N of West Philadelphia
Cause
Heavy Rain
Property damage
$30,000
Reported by
Public
Coordinates
39.935, -75.208

North Beechwood Street flooded with water almost halfway up the side of multiple cars.

What these are

Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Pennsylvania in 2026Every state in 2026This day in weather historyWarnings in Pennsylvania, June 2026

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1343121, 1343122, 1343124.