FXUS61 KPHI 261741

AFDPHI



Area Forecast Discussion

National Weather Service Mount Holly NJ

141 PM EDT Thu Jun 26 2025



.SYNOPSIS...

The strong upper level ridge to our southwest is weakening,

allowing a back door cold front to track though much of the 

forecast area through Friday. The front will then push back to 

the north as a warm front on Saturday and Sunday with high 

pressure remaining in control into Monday. Another cold front 

looks to cross through the area on Tuesday.



&&



.NEAR TERM /THROUGH FRIDAY/...

As of early this afternoon, the back door cold front stretches

from near Allentown south to near Philly and southeast towards

Atlantic City. Locations north and east have cooled and clouded

up considerably. Further south and west, warmth and humidity

remain, and in fact it turned out the need was present to expand

the heat advisories up into Philly metro once again as heat

indices are meeting the early-season criteria once again. 



Where the front has yet to reach, heat and instability have

increased, and storms are starting to develop. As these storms

start to intersect the southwestward moving front, they may

stall on the boundary, which could result in a locally heavy

rain and flood threat. HREF was most bullish across areas just

northwest and southwest of our forecast area, but enough of a

signal is present to give us confidence in posting a flood watch

for our westernmost zones in PA thru this evening. Storms may

make their way further east, with a lesser but still present

heavy rain threat, but the highest risk definitely appears to 

be in the far west. An isolated severe storm also can't be ruled

out given the instability. 



Later tonight as convection winds down, the front will sweep

southwest and blanket most of the region with low clouds and a

much cooler east to northeast wind. Lows will be in the 50s

Poconos, 60s most elsewhere, but near 70 southern Delmarva

zones. 



A low cloud deck will dominate Friday on the easterly flow north

of the front, which will stall just to our south. Some showers

and spotty thunderstorms may develop via disturbances passing

aloft and elevated instability, but severe and flood risk look 

lower. Temperatures will struggle to reach 70 across 

north/central NJ, likely failing to do so in the Poconos, but 

may touch 80 across the eastern shore of MD and far southern DE.



&&



.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...

The wavy front nearby and low pressure moving along it will 

keep clouds and showers across the area Thursday night and 

Friday. Friday will be noteworthy with high temps probably only 

topping out in the upper 60s/low 70s across the north and 

mid/upper 70s for Delmarva and south NJ. These highs are some 20

degrees less than recent days. We'll have mostly chance pops 

for showers/tstms from Thursday night thru Friday night with the

greater chances for the N/W counties and lesser POPS for S/E 

areas. On Saturday, the fronts draw nearer and Likely POPs are 

in the grids for N/W areas with high chance pops for E/SE areas.

Highs Sat will snap back to slightly above normal levels with 

85 to 90 degree temps again most spots with low 80s N/W.



&&



.LONG TERM /SUNDAY THROUGH THURSDAY/...

The storm track will remain nearby late this weekend and into the 

beginning/middle parts of next week. The strong ridge that has been 

across the area lately will have diminished and moved offshore. This 

will keep the extreme heat away from the area. Still, temperatures 

will be near normal Sunday followed by slightly above normal 

readings for Monday thru Wednesday. Readings are not expected to be 

record setting like this past week has been. Highs will mostly be 

upper 80s with some low 90s across the S/E areas and low/mid 80s for 

north NJ and the southern Poconos. Lows will mostly be in the upper 

60s to low 70s with some mid 70s in urban areas. 



Another result of the storm track being nearby will ensure more 

showers and clouds for the long term. There are chances for 

showers/tstms each day with Tue having the highest POPs (low likely 

range mostly) and low numbers for Wednesday when POPs are only 

slight chance attm. Upper troughing develops later next week, so 

more showers and normal temps (if not below) may arrive later next 

week. The different models offer with the degree of troughing, so 

there is uncertainty with how mild it will actually be.



&&



.AVIATION /18Z THURSDAY THROUGH TUESDAY/...

Rest of today...Mainly VFR, but sub-VFR possible mainly from 

PHL north and east as backdoor front brings stratus deck. Spotty

showers/t-storms possible during the afternoon especially 

western terminals. Winds turning northeasterly 5-10 kts. Low 

confidence.



Tonight...Sub-VFR conditions likely with IFR possible. Scattered

storms this evening give way to widespread low stratus later at

night. Winds northeast to east 5-10 kts. Low confidence.



Friday...Sub-VFR conditions likely with IFR possible. Scattered

showers possible, but main concern will be continued low stratus

deck which likely lingers most if not all day. Winds still east

to northeast 5-10 kts. Low confidence.



Outlook...



Friday night...Plenty of low clouds and showers expected with 

onshore flow across the area. Mostly areas with have low-end 

MVFR with IFR strongly possible too. 



Saturday thru Monday... Largely VFR but a few showers/tstms at 

times with lower CIGs/VSBYs expected.



&&



.MARINE...

Small Craft Advisory thru Friday afternoon for northern two NJ 

marine zone given northeast flow gusting 25-30 kts which likely 

continues into Friday, with seas building to 3-5 feet. Rest of 

zones should see NE winds 10-15 kts with some gusts up to 20 

kts thru Friday and seas of 2-4 feet. A spotty gusty 

thunderstorm possible this afternoon/evening. 



Outlook... 



Winds and seas will be below SCA levels for Friday and into the

weekend. The biggest hazard will be scattered tstms for the 

periods. The mostly likely times will be afternoons into the 

early evening period.



&&



.TIDES/COASTAL FLOODING...

The recent New Moon and increasing onshore flow will lead to higher

confidence in advisory level tidal flooding occurring this evening.

While we get away from the New Moon, onshore flow will result in

water piling up and more widespread minor tidal flooding for the

coastal and Delaware Bay communities. It appears that the higher

water levels will only be for one tide cycle, but we'll monitor

later today to assure that this trend continues. 



No tidal flooding is expected within the tidal Delaware River or 

Chesapeake Bay.



&&



.PHI WATCHES/WARNINGS/ADVISORIES...

PA...Heat Advisory until 8 PM EDT this evening for PAZ070-071-102-

     104.

     Flood Watch until midnight EDT tonight for PAZ054-060-061-101-

     102.

NJ...Heat Advisory until 8 PM EDT this evening for NJZ017-018.

     Coastal Flood Advisory from 7 PM this evening to 1 AM EDT 

     Friday for NJZ012>014-020-022>027.

DE...Heat Advisory until 8 PM EDT this evening for DEZ001>003.

     Coastal Flood Advisory from 7 PM this evening to 1 AM EDT 

     Friday for DEZ003-004.

MD...Heat Advisory until 8 PM EDT this evening for MDZ012-015-019-

     020.

MARINE...Small Craft Advisory until 6 PM EDT Friday for ANZ450-451.



&&



$$



SYNOPSIS...OHara/RCM

NEAR TERM...RCM

SHORT TERM...OHara

LONG TERM...OHara

AVIATION...OHara/RCM

MARINE...OHara/RCM

TIDES/COASTAL FLOODING...PHI

