Heat Advisory 7, NWS Philadelphia/Mount Holly

820 
WWUS71 KPHI 181643
NPWPHI

URGENT - WEATHER MESSAGE
National Weather Service Mount Holly NJ
1243 PM EDT Sat Jul 18 2026

DEZ003-190000-
/O.EXA.KPHI.HT.Y.0007.000000T0000Z-260719T0000Z/
Inland Sussex-
Including the cities of Georgetown
1243 PM EDT Sat Jul 18 2026

...HEAT ADVISORY IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 106 degrees expected.

* WHERE...Inland Sussex County.

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of 
the sun, and check up on relatives and neighbors.

&&

$$

MDZ015-019-020-190000-
/O.CON.KPHI.HT.Y.0007.000000T0000Z-260719T0000Z/
Queen Annes-Talbot-Caroline-
Including the cities of Denton, Easton, and Centreville
1243 PM EDT Sat Jul 18 2026

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING...

* WHAT...Heat index values up to 106 degrees expected.

* WHERE...Caroline, Queen Annes, and Talbot Counties.

* WHEN...Until 8 PM EDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out of 
the sun, and check up on relatives and neighbors.

&&

$$

AKL

898 
WWUS71 KPHI 182315
NPWPHI

URGENT - WEATHER MESSAGE
National Weather Service Mount Holly NJ
715 PM EDT Sat Jul 18 2026

DEZ003-MDZ015-019-020-190015-
/O.CAN.KPHI.HT.Y.0007.000000T0000Z-260719T0000Z/
Inland Sussex-Queen Annes-Talbot-Caroline-
Including the cities of Georgetown, Centreville, Denton, and
Easton
715 PM EDT Sat Jul 18 2026

...HEAT ADVISORY IS CANCELLED...

Cooler air has filtered in, and thus the threat for extreme heat has 
ended.

$$

SFJ

Area Forecast Discussion
National Weather Service Mount Holly NJ
151 AM EDT Sat Jul 18 2026

.WHAT HAS CHANGED...
The Aviation section was updated to account for the 06Z TAFs.

&&

.KEY MESSAGES...
1. Smoke from Canadian wildfires will remain in the area tonight
through at least the first part of Saturday.

2. Widespread severe weather as well as flash flooding will be
possible for Saturday into Saturday night. Conditions will also be
warm and very humid.

3. Mainly fair and dry weather is expected for Sunday through Monday
before the next chance for shower and storms returns by late
Tuesday.

&&

.DISCUSSION...
KEY MESSAGE 1...Smoke from Canadian wildfires will remain in the
area tonight through at least the first part of Saturday.

Smoke from the Canadian wildfires continues to impact the
region this afternoon, though much of the area has seen some
improvement in visibility since earlier this morning. The
improvement has occurred due to continuing northerly winds
pushing the smoke a bit farther south. Unfortunately, as we get
into this evening and overnight the flow will be turning more
southerly and this will likely result in deteriorating
conditions again over portions of eastern PA and New Jersey.
Expect that visibility may once again get down to 1 to 2 miles.
These conditions likely linger into Saturday morning before the
continuing southerly flow should start to push the smoke out
Saturday afternoon into Saturday evening. Expected convection
(see below) may also help improve things.

KEY MESSAGE 2...Widespread severe weather as well as flash
flooding will be possible for Saturday into Saturday night.
Conditions will also be warm and very humid.

Bottom line up front: There is an increasing threat for relatively
widespread severe weather and flash flooding for Saturday into
Saturday night. A Flood Watch is now in effect for a large portion
of the area from the urban corridor northward starting at 10 AM and
continuing until 2 AM Sunday. Also, the Storm Prediction Center has
now placed the region in an Enhanced risk for severe weather. This
means that instances of severe weather could be fairly widespread
across the area compared to the more typical scattered coverage that
we often see. The greatest threat will be for damaging winds but
there is also the threat of a few tornadoes. The greatest threat for
severe weather looks to be between noon and 10 PM.

Getting into the weeds, low pressure will be advancing through the
Great Lakes tonight before moving into portions of eastern Ontario
and southern Quebec by late Saturday. This will push a warm front
through in the morning followed by a cold front later at night. We
are still expecting there will be multiple rounds of showers and
storms that occur.

The first looks like it will move through around mid morning to
midday Saturday and affect areas mainly near and especially
north of the urban corridor. Heavy rainfall with the potential
for flash flooding will be possible but the risk of severe
weather looks relatively lower compared to later in the day.

Following this first round most areas should see a break of
several hours in the afternoon. It is during this time that
temperatures and dew points ramp up. Generally expect highs in
the 80s with heat indices of over 90 for much of the area with
the potential for heat indices to hit near 100 to 105 near and
south of around Philly where highs will range from the upper 80s
to mid 90s. This will be very close to advisory criteria but
given some uncertainty on how warm we get due to cloud cover and
the earlier convection, we are holding off on any heat products
at this time.

ML CAPE values look to really surge in the afternoon as well
aided by the very high dew points. CAPE should max out at least
in the 1500-2500 range with the potential for it to even go
3000+ depending on how warm we get. In addition, deep layer
shear looks to be 40-50 knots with strong low level shear and
turning of the winds as well. The anomalously high dew points
expected will also help LCL values get quite low with PWAT
values progged to surge to over 2.2 inches. The upshot is that
the second round of storms that will likely arrive during the
latter part of the afternoon into the evening will be easily
capable of producing damaging winds and torrential rainfall
leading to flash flooding.

Expect convection to take the form of multi-cell clusters
and/or line segments with the potential for embedded supercells.
A few tornadoes will also be possible. In fact the SPC has much
of the area in a relatively rarely issued for this area 5% risk
of tornadoes.

In terms of the heavy rainfall and associated flash flood
threat, this looks to be highest from northern Delaware to South
Jersey on northward where we have the Flood Watch in effect.
Given the very high PWATs described above, storms will be
capable of producing rain amounts of 2-3 inches within a period
of just 1-2 hours. The flood threat will be greatest for urban,
low lying areas, and areas near streams and creeks. Areas that
get hit hard repeatedly by the multiple rounds of convection
will also be particularly vulnerable. And in fact there will be
the potential for a final round of convection to move through
later Saturday evening just ahead of the actual cold front.

Showers/storms should finally wind down heading into the overnight
period Saturday night as the cold front pushes through.

KEY MESSAGE 3...Mainly fair and dry weather is expected for Sunday
through Monday before the next chance for shower and storms returns
by late Tuesday.

Following the passage of a cold front later Saturday night into
early Sunday, the rest of the day Sunday is shaping up to feature
sunshine with both lower temperatures and lower humidity levels.
Generally expect highs ranging from the 70s to near 80 over our
northern zones over NE PA into NW NJ with low to mid 80s near the
urban corridor and upper 80s over portions of our eastern MD shore
counties and southern Delaware. Dew points will be much lower
compared to Saturday so the heat indices will be close to the actual
air temperatures.

High pressure builds in to start the week Monday with temperature
and humidity levels even a bit lower than Sunday under mainly sunny
skies and light winds. However looking beyond this time, the next
frontal system approaches Tuesday with heat and humidity returning
ahead of it and showers/storms likely by late day into Tuesday night
as the system moves through. This is still several days out but it's
worth noting that WPC and SPC are already indicating threats for
heavy rainfall and flash flooding as well as severe storms. Expect
highs Tuesday generally in the 80s to near 90 with heat indices as
high as the mid to high 90s from around the urban corridor extending
southward. It's possible some showers storms linger into Wednesday
but the general trend should be towards improving
conditions...especially by late day.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Thru 12Z this morning...MVFR/IFR VSBYs in FU. Light S-SW winds.
Low confidence.

Today...Low VSBYs in FU improve in the morning. Several waves
of SHRA/TSRA throughout the day, starting in the morning, with
sub-VFR conds. Stronger TSRA will be capable of brief wind gusts
in excess of 50 kt. Outside of TSRA, winds will be out of the
S-SW 5 to 10 kt. Low confidence.

Tonight...Sub-VFR conds in lingering SHRA/TSRA. Low confidence.

Outlook...

Sunday through Sunday night...Lingering sub-VFR conds at KACY
Sunday morning. Otherwise, VFR.

Monday...VFR.

Tuesday through Wednesday...Sub-VFR in SHRA/TSRA from time to
time.

&&

.MARINE...
No marine headlines are in effect through early Saturday.
Generally expect Southeast winds becoming southerly tonight and
increasing to around 10 knots. Seas around 2 feet through early
Saturday.

Wildfire smoke will continue to filter into the region through
early Saturday. This may cause localized areas of visibility
restrictions. Will have to monitor observations closely as
denser smoke passes through the region, where marine dense smoke
advisories may become warranted if visibilities drop to 1 mile
or less, but at this time it appears more unlikely.

By Saturday winds shift more south-southwest and increase ahead
of a strong cold front. A Small Craft Advisory is in effect for
all ocean zones starting at Noon Saturday and running until
midnight for our southern two zones off the coast of Delaware
and adjacent to the Delaware Bay. Farther north, the SCA runs
until 4 AM Sunday. Expect winds gusting to around 30 knots with
seas getting up to 5-6 foot range. Showers and thunderstorms
will become increasingly likely as well.

Outlook...

Sunday...Seas may linger near SCA levels early in the day but
otherwise the conditions should be sub SCA.

Monday...Fair weather expected with winds under 25 knots and seas
around 2-3 feet.

Tuesday - Wednesday...Winds and seas likely approach SCA levels
by late day Tuesday and could linger into Wednesday.

Rip Currents...

For Saturday, south winds strengthen to around 15-20 MPH (with
the exception of Monmouth County where winds will be a bit
lighter). Winds will have an onshore component for Cape May
County, Atlantic County, and Ocean County in NJ and be more
shore parallel for the Delaware Beaches and Monmouth County
beaches. Ended up going a MODERATE risk for rip currents where
the winds are strongest and where there is an onshore component
(Cape May, Atlantic, Ocean), with a LOW risk elsewhere (Monmouth
and Sussex). Breaking waves start around 1 to 2 feet, but
gradually increase through the day to around 2 to 3 feet. The
wave period will be around 8 seconds. Given lower wave heights
and a short to medium period, thinking a high risk is not
necessary at this time.

For Sunday, winds turn offshore, becoming northwesterly up to 10
MPH. Still a medium period swell with wave heights around 2 feet
as well. All of this will result in a LOW risk for rip currents
at all beaches.

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

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Flood Watch from 10 AM EDT this morning through late tonight
     for PAZ054-055-060>062-070-071-101>106.
NJ...Flood Watch from 10 AM EDT this morning through late tonight
     for NJZ001-007>010-012>020-026-027.
DE...Flood Watch from 10 AM EDT this morning through late tonight
     for DEZ001.
MD...None.
MARINE...Small Craft Advisory from noon today to 4 AM EDT Sunday for
     ANZ450>453.
     Small Craft Advisory from noon today to midnight EDT tonight
     for ANZ454-455.

&&

DISCUSSION...Fitzsimmons/Hoeflich
AVIATION...MPS/RCM
MARINE...Fitzsimmons/Hoeflich/RCM

Hazardous Weather Outlook
National Weather Service Mount Holly NJ
505 AM EDT Fri Jul 17 2026

MDZ012-015-019-020-180915-
Kent MD-Queen Annes-Talbot-Caroline-
505 AM EDT Fri Jul 17 2026

This Hazardous Weather Outlook is for northeast Maryland.

.DAY ONE...Today and tonight.

Hazardous weather is not expected at this time.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

Thunderstorms may produce severe weather and flash flooding
Saturday.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
834 PM EDT Fri Jul 17 2026

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

0626 PM     Hail             2 E Warren Grove        39.76N 74.32W
07/16/2026  E1.50 Inch       Ocean              NJ   Public

            Delayed report. Reported at the Pinewood
            Estates neighborhood via photo from social
            media. Time estimated from radar.

&&

Staarmann

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
839 PM EDT Fri Jul 17 2026

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

0706 PM     Hail             Surf City               39.66N 74.17W
07/16/2026  E1.00 Inch       Ocean              NJ   Cocorahs

            Quarter sized hail reported by CoCoRaHS
            station NJ-OC-113 in Surf City. Time
            included in report. Hail began at 7:06 PM
            and continued until 7:15 PM.

&&

Staarmann

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
840 PM EDT Fri Jul 17 2026

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

0730 PM     Hail             Ship Bottom             39.64N 74.18W
07/16/2026  E0.50 Inch       Ocean              NJ   Trained Spotter

&&

Staarmann

Preliminary Local Storm Report...Summary
National Weather Service Mount Holly NJ
842 PM EDT Fri Jul 17 2026

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

0429 PM     Tstm Wnd Dmg     1 S Eastampton Twp      39.98N 74.75W
07/16/2026                   Burlington         NJ   Public

            Large tree down across Smithville Road. Time
            estimated from radar.

0534 PM     Marine Tstm Wind 2 SSW Barnegat Light    39.73N 74.12W
07/16/2026  M44 MPH          Ocean              NJ   Mesonet

            Personal Weather Station: Hidden Bay -
            KNJLONGB101.

0539 PM     Marine Tstm Wind 3 N Barnegat Light      39.80N 74.12W
07/16/2026  M41 MPH          Ocean              NJ   Mesonet

            Personal Weather Station: Sedge Island -
            KNJWARET3.

0609 PM     Marine Tstm Wind 1 SSE Bay Side          39.66N 74.21W
07/16/2026  M76 MPH          ANZ451             NJ   Mesonet

            WeatherFlow - LBI Island Surf - XLBI gusted
            to 76 mph at 609pm.

0612 PM     Tstm Wnd Dmg     Barnegat                39.75N 74.22W
07/16/2026                   Ocean              NJ   911 Call Center

            Multiple trees and wires down across
            Barnegat Township. Time estimated from
            radar.

0614 PM     Marine Tstm Wind 1 SSW Ship Bottom       39.63N 74.19W
07/16/2026  M48 MPH          Ocean              NJ   Mesonet

            Personal Weather Station: Blue Beach House -
            KNJLONGB193.

0626 PM     Hail             2 E Warren Grove        39.76N 74.32W
07/16/2026  E1.50 Inch       Ocean              NJ   Public

            Delayed report. Reported at the Pinewood
            Estates neighborhood via photo from social
            media. Time estimated from radar.

0629 PM     Marine Tstm Wind 1 W Barnegat Light      39.76N 74.13W
07/16/2026  M45 MPH          Ocean              NJ   Mesonet

            PWS: High Bar - KNJBARNE131.

0635 PM     Marine Tstm Wind Harvey Cedars           39.70N 74.14W
07/16/2026  M48 MPH          Ocean              NJ   Mesonet

            Mesonet station NJ11 Harvey Cedars.

0639 PM     Tstm Wnd Dmg     Stafford Twp            39.71N 74.28W
07/16/2026                   Ocean              NJ   911 Call Center

            Trees and wires down across Stafford
            Township. Time estimated from radar.

0640 PM     Hail             1 S Warren Grove        39.75N 74.37W
07/16/2026  E1.25 Inch       Ocean              NJ   Public

            Picture relayed on social media of hail
            approximately half dollar size.

0647 PM     Flood            1 SSW Manahawkin        39.68N 74.27W
07/16/2026                   Ocean              NJ   Broadcast Media

            Water covering roadways in Mayetta.

0649 PM     Tstm Wnd Gst     Ship Bottom             39.65N 74.19W
07/16/2026  M77 MPH          Ocean              NJ   Mesonet

            Personal Weather Station: Terrace View -
            KNJSHIPB12 gusted to 76.5 mph at 649pm.

0650 PM     Marine Tstm Wind 1 W Bay Side            39.67N 74.23W
07/16/2026  M53 MPH          Ocean              NJ   Mesonet

            PWS: MTBHWNJ - KNJMANAH135 gusted to 53 mph
            at 650pm.

0650 PM     Tstm Wnd Gst     Surf City               39.66N 74.17W
07/16/2026  M84 MPH          Ocean              NJ   Mesonet

            Personal Weather Station: SCYC - Surf City
            Yacht Club - KNJSURFC12 gusted to 84 mph at
            650pm.

0650 PM     Tstm Wnd Dmg     Surf City               39.66N 74.17W
07/16/2026                   Ocean              NJ   911 Call Center

            Widespread trees and wires down across Surf
            City. Time estimated from radar.

0654 PM     Marine Tstm Wind 3 SSW Ship Bottom       39.61N 74.20W
07/16/2026  M41 MPH          Ocean              NJ   Mesonet

            PWS: Jersey Beach Weather - KNJBEACH88.

0656 PM     Flash Flood      Stafford Twp.           39.69N 74.25W
07/16/2026                   Ocean              NJ   911 Call Center

            Portions of Route 72 in Stafford Twp became
            impassable due to water. Some vehicles were
            disabled.

0704 PM     Hail             Manahawkin              39.69N 74.25W
07/16/2026  E1.00 Inch       Ocean              NJ   Public

            Report from mPING: Quarter (1.00 in.).

0706 PM     Hail             Surf City               39.66N 74.17W
07/16/2026  E1.00 Inch       Ocean              NJ   Cocorahs

            Quarter sized hail reported by CoCoRaHS
            station NJ-OC-113 in Surf City. Time
            included in report. Hail began at 7:06 PM
            and continued until 7:15 PM.

0707 PM     Hail             1 SE Stafford Twp.      39.68N 74.24W
07/16/2026  M1.00 Inch       Ocean              NJ   Public

            Report from mPING: Quarter (1.00 in.).

0708 PM     Tstm Wnd Dmg     2 WNW Ocean Acres       39.75N 74.31W
07/16/2026                   Ocean              NJ   Dept of Highways

            Corrects previous tstm wnd dmg report from 2
            WNW Ocean Acres. Downed Tree on NJ 72 Both
            Directions West of Ivy Rd (Stafford Twp),
            All lanes closed eastbound; All lanes closed
            westbound. Time estimated from radar.

0714 PM     Marine Tstm Wind Holgate                 39.54N 74.26W
07/16/2026  M39 MPH          Ocean              NJ   Mesonet

            PWS: HolgateNJ - KNJLONGB137.

0730 PM     Hail             Ship Bottom             39.64N 74.18W
07/16/2026  E0.50 Inch       Ocean              NJ   Trained Spotter

0730 PM     Hail             1 WNW Manahawkin        39.70N 74.28W
07/16/2026  M1.00 Inch       Ocean              NJ   Public

            Measured 1 inch hail.

0749 PM     Tstm Wnd Gst     1 SSW Ship Bottom       39.63N 74.19W
07/16/2026  M58 MPH          Ocean              NJ   Mesonet

            PWS: 36th Street Brant Beach - KNJBEACH112
            gusted to 58 mph at 749pm.

0803 PM     Tstm Wnd Dmg     Eagleswood Twp          39.65N 74.29W
07/16/2026                   Ocean              NJ   911 Call Center

            Corrects previous tstm wnd dmg report from
            Eagleswood Twp. Multiple trees and wires
            down across Eagleswood Twp. Time estimated
            from radar.

&&

Staarmann