060
FXUS61 KPHI 061226
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
826 AM EDT Thu Jun 6 2024

.SYNOPSIS...
A cold front will cross the region later this afternoon into
tonight. A series of shortwaves will pivot through the region
this weekend with some unsettled weather at times. High pressure
will return early next week and persist into the middle of next
week.

&&

.NEAR TERM /THROUGH TONIGHT/...
The warm front is north of the area, and most of the showers
have ended, though there are a few stragglers out there. Will
keep a slight chance for showers for the next couple of hours
for most of New Jersey and portions of southeast Pennsylvania.
to cover this. Patchy fog continues to lift and dissipate as
well. With surface dew points well in the 60s and low 70s, it
will be quite humid today with highs in the upper 70s to mid 80s
across much of the area. Max heat index values will be in the
mid 80s to near 90 in some spots during the afternoon.

Otherwise, the main concern going into the afternoon will be
another round of showers and thunderstorms as the cold front
approaches from the northwest. Taking a look at the environment
from available forecast soundings, much of the area will settle
within a corridor of SBCAPE near 1500-2000 J/kg and effective
bulk shear values near 20-25 kt. This suggests that there should
be at least some organized updrafts despite weak lapse rates
and rather unidirectional shear. As a result, the Storm
Prediction Center has maintained a Marginal Risk (Level 1/5) for
the region today with the primary threat being damaging wind
gusts as DCAPE values will be around 1000 J/kg. PWATs will again
be around 2 inches, so locally heavy rain is possible.

Hi-res guidance depict that storms will fire as early as mid-day
north and west, before tracking east-southeast through the afternoon
for the northern half of the area. For the southern half of the
area, the CAMs and other hi-res guidance continue to hint on a
potential linear line of storms across southern NJ and into the
Delmarva later in the afternoon. Will have to continue to monitor
this potential as we progress through the day.

By the early evening, showers and thunderstorms will come to an end
as the front moves offshore. In wake of the front, dew points will
fall back into the 50s to around 60 degrees and skies will clear
into early Friday morning. Low temps will be in the upper 50s to mid
60s, but it will feel much more comfortable thanks to the lower dew
points!

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
Things have trended drier for the end of the week and first
half of the weekend. The upper level low will slowly move
eastward through the northern Great Lakes and Ontario. A series
of shortwaves will rotate around the base of the low both Friday
and Saturday. This will result in some scattered showers and
isolated thunderstorms developing in the afternoon/evening of
both days, mainly from the I-78 corridor on north. South of that
area, it should stay dry with mostly sunny to partly cloudy
skies. Temperatures both days will be in the upper 70s/low 80s.
Not expecting any severe weather however.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
The aforementioned upper trough and low will meander across
southern Canada and the northern Great Lakes through early next
week. As it does so, multiple shortwaves will round through the
upper trough resulting in several rounds of showers and
occasional thunderstorms through the weekend into next week.
While no singular day appears to be a washout, there will be
quite a bit of showers around, more likely north and west of
Philadelphia with drier conditions south and east. The highest
probability of precipitation will be during the afternoon hours
as diurnal heating allows instability to be maximized.

More uncertainty comes for the start of next week as guidance
diverges after Sunday. Though there is a decent chance it
remains unsettled, but similar to the weekend, severe weather
impacts do not appear on the table.

Temperatures during this period will remain quite seasonable
for early June with a mix of 70s/80s during the day and 50s/60s
at night.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...MVFR/IFR CIGs are likely to continue through the morning
hours before lifting to VFR in the afternoon. A cold front will
approach from the west, bringing the return of some
thunderstorms during the afternoon. CIGs/VSBYs restrictions are
possible in any thunderstorm. SW winds around 10 kt with gusts
up to 20 kt. Moderate confidence.

Tonight...Showers and thunderstorms should wane after 01-02Z.
Skies should begin to clear through the overnight hours. All
terminals should be VFR tonight. W-NW winds around 5-8 kt.
Moderate confidence.

Outlook...

Friday...Primarily VFR though some showers/thunderstorms
(20-30%) possible at KRDG/KABE. Wind gusts out of the west in
the upper teens/low 20s anticipated.

Friday Night...VFR. No significant weather.

Saturday through Wednesday...Conditions will mainly be VFR but
each day features shower chances and the possibility of
restrictions, mainly in the afternoon/early evening. Best chance
each day to see showers and restrictions will be at the Lehigh
Valley terminals.

&&

.MARINE...
Small Craft Advisory is now in effect for DE ocean waters as
44009 is gusting to 27 kt. Otherwise, SW winds will continue to
increase, gusting to around 25 kt and seas nearing 5 feet
through much of this afternoon. As a result, a Small Craft
Advisory is in effect beginning at 11 AM this morning through
tonight for NJ ocean waters. No headlines are in effect for the
Delaware Bay today.

Fair weather is expected this morning, before another round of
showers and thunderstorms are expected this afternoon with an
approaching cold front. Fair weather should return in wake of the
front with sub-SCA conditions late.

Outlook...

Friday through Tuesday...No marine headlines expected. Fair
weather outside of some showers on Sunday Night.

Rip Currents...

For today, SSW winds around 20 mph will parallel the shoreline
for NJ and offshore for DE beaches. With breaking waves of 2-3
feet, a medium period swell, and a new moon, the risk for rip
current development is MODERATE for the more southeasterly
facing beaches in New Jersey beaches and LOW for the more
easterly facing beaches in New Jersey and Delaware.

For Friday, winds become a bit more westerly but still have a
southwesterly overall direction, and though slightly lighter,
should still be parallel enough to the southeasterly facing
beaches in New Jersey for a MODERATE risk, with LOW elsewhere.

Rip currents occur often in the vicinities of jetties and
piers. Utilize any guarded beaches if venturing out into the
water. For specific beach forecasts, visit weather.gov/beach/phi

&&

.TIDES/COASTAL FLOODING...
The threat for widespread minor flooding increases as winds
strengthen then turn and become shore parallel today,
potentially trapping water along the coast. In addition, tide
cycles will be elevated due to the New Moon today. Will
continue to monitor upcoming high tides and make adjustments to
the forecast accordingly. Additional Coastal Flood Advisories
may be needed for tonight`s high tide cycle.

Overall, the threat for tidal flooding appears to be lower
along the Chesapeake Bay than elsewhere in the region but by the
early morning high tide today, water levels may also approach
spotty minor.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 2 AM EDT Friday for ANZ450>453.
     Small Craft Advisory until 6 PM EDT this evening for ANZ454-
     455.

&&

$$

SYNOPSIS...DeSilva/MJL
NEAR TERM...DeSilva/MPS
SHORT TERM...Hoeflich
LONG TERM...Deal/Hoeflich
AVIATION...DeSilva/Hoeflich/MJL/MPS
MARINE...DeSilva/Hoeflich/MPS
TIDES/COASTAL FLOODING...